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Taiga Shield Ecozone+ Evidence for Key Findings Summary

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Canadian Biodiversity: Ecosystem Status and Trends 2010

Evidence for Key Findings Summary Report No. 9
Published by the Canadian Councils of Resource Ministers

Document Information

Cover page

Library and Archives Canada Cataloguing in Publication

Taiga Shield Ecozone+ Evidence for Key Findings Summary.

Issued also in French under title:
Sommaire des éléments probants relativement aux constatations clés pour l'écozone+ de la Taïga du Bouclier.
Electronic monograph in PDF format.
Cat. no.: En14-43/0-9-2014E-PDF
ISBN 978-1-100-23547-9

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Cover photos: Tree line, Singing Lake, NWT, © C. O'Brien; Lichen and shrub-covered palsas surrounded by a pond resulting from melting permafrost in a bog near the village of Radisson, QC, Serge Payette

This report should be cited as:
ESTR Secretariat. 2014. Taiga Shield ecozone+ evidence for key findings summary. Canadian Biodiversity: Ecosystem Status and Trends 2010, Evidence for Key Findings Summary Report No. 9. Canadian Councils of Resource Ministers. Ottawa, ON. vii + 80 p.

© Her Majesty the Queen in Right of Canada, 2014
Aussi disponible en français

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Preface

The Canadian Councils of Resource Ministers developed a Biodiversity Outcomes FrameworkFootnote 1 in 2006 to focus conservation and restoration actions under the Canadian Biodiversity Strategy.Footnote 2 Canadian Biodiversity: Ecosystem Status and Trends 2010Footnote 3 was the first report under this framework. It presents 22 key findings that emerged from synthesis and analysis of reports prepared as part of this project. These technical reports present status and trends information and analyses for many cross-cutting national themes (the Technical Thematic Report Series) and for Canada's terrestrial and marine ecozones+ (the Ecozone+ Status and Trends Assessments). More than 500 experts participated in data analysis, writing, and review of these foundation documents. Summary reports were also prepared for each terrestrial ecozone+ to present the ecozone+-specific evidence related to each of the 22 national key findings (the Evidence for Key Findings Summary Report Series). Together, the full complement of these products constitutes the 2010 Ecosystem Status and Trends Report (ESTR):

2010 Ecosystem Status and Trends Report (ESTR)
Report

This report, Taiga Shield Ecozone+ Evidence for Key Findings Summary, presents evidence related to the 22 national key findings and is therefore not a comprehensive assessment of all ecosystem-related information. The level of detail presented on each key finding varies and important issues or datasets may have been missed. As in all ESTR products, the time frames over which trends are assessed vary – both because time frames that are meaningful for these diverse aspects of ecosystems vary and because the assessment is based on the best available information, which is over a range of time periods.

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Ecological Classification System – Ecozones+

A slightly modified version of the Terrestrial Ecozones of Canada, described in the National Ecological Framework for Canada, Footnote 4 provided the ecosystem-based units for all reports related to this project. Modifications from the original framework include: adjustments to terrestrial boundaries to reflect improvements from ground-truthing exercises; the combination of three Arctic ecozones into one; the use of two ecoprovinces – Western Interior Basin and Newfoundland Boreal; the addition of nine marine ecosystem-based units; and, the addition of the Great Lakes as a unit. This modified classification system is referred to as "ecozones+" throughout these reports to avoid confusion with the more familiar "ecozones" of the original framework. Footnote 5 The northern boundary of the western section of the Taiga Shield ecozone was adjusted based on ground-truthing of the original boundaries.

Ecological Classification Framework for the Ecosystem Status and Trends Report for Canada.
map
Long Description for Ecozones+ map of Canada

This map of Canada shows the ecological classification framework for the Ecosystem Status and Trends Report, named "ecozones+". This map shows the distribution of 15 terrestrial ecozones+ (Atlantic Maritime; Newfoundland Boreal; Taiga Shield; Mixedwood Plains; Boreal Shield; Hudson Plains; Prairies; Boreal Plains; Montane Cordillera; Western Interior Basin; Pacific Maritime; Boreal Cordillera; Taiga Cordillera; Taiga Plains; Arctic), two large lake ecozones+ (Great Lakes; Lake Winnipeg), and nine marine ecozones+ (North Coast and Hecate Strait; West Coast Vancouver Island; Strait of Georgia; Gulf of Maine and Scotian Shelf; Estuary and Gulf of St. Lawrence; Newfoundland and Labrador Shelves; Hudson Bay, James Bay and Fox Basin; Canadian Arctic Archipelago; Beaufort Sea).

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Acknowledgements

This summary report is based on the draft Taiga Shield ecozone+ Status and Trends Assessment that was prepared by Anne Gunn and Joan Eamer. Additional reviews of this summary report were provided by scientists and resource managers from relevant provincial and federal government agencies, as well as two external expert reviewers. Further information about this ecozone+ can be found in the associated supplementary material for the Taiga Shield ecozone+.
Contributions to the draft Status and Trends Assessment are listed below.

Taiga Shield ecozone+ Draft Status and Trends Assessment acknowledgements

Lead authors:
A. Gunn and J. Eamer

Contributing authors:
D. Cantin and S. Carrière

Contributing authors, specific sections or topics
Aboriginal communities of the Taiga Shield: A. Penn
La Grande hydro complex, fish and mercury sections (Hydro-Québec): R. Verdon, R. Schetagne and R. Lussier

Authors of ESTR Thematic Technical Reports from which material is drawn
Large-scale climate oscillations influencing Canada, 1900-2008: B. Bonsal and A. Shabbar Footnote 6
Canadian climate trends, 1950-2007: X. Zhang, R. Brown, L. Vincent, W. Skinner, Y. Feng and E. MekisFootnote 7
Trends in large fires in Canada, 1959-2007: C.C. Krezek-Hanes, F. Ahern, A. Cantin and M.D. FlanniganFootnote 8
Wildlife pathogens and diseases in Canada: F.A. LeightonFootnote 9
Trends in breeding waterfowl in Canada: M. Fast, B. Collins and M. Gendron Footnote 10
Trends in permafrost conditions and ecology in northern Canada: S. SmithFootnote 11
Northern caribou population trends in Canada: A. Gunn, D. Russell and J. EamerFootnote 12
Woodland caribou, boreal population, trends in Canada: C. Callaghan, S. Virc and J. DuffeFootnote 13
Landbird trends in Canada, 1968-2006: C. Downes, P. Blancher and B. CollinsFootnote 14
Trends in Canadian shorebirds: C. Gratto-Trevor, R.I.G. Morrison, B. Collins, J. Rausch and V. JohnstonFootnote 15
Monitoring ecosystems remotely: a selection of trends measured from satellite observations of Canada: F. Ahern, J. Frisk,R. Latifovic and D. PouliotFootnote16
Biodiversity in Canadian lakes and rivers: W.A. Monk and D.J. BairdFootnote 17

Review
conducted by scientists and renewable resource and wildlife managers from relevant territorial and federal government agencies through a review process recommended by the ESTR Steering Committee. Additional reviews of specific sections were conducted by university researchers in their field of expertise at the request of the authors.

Direction
provided by the ESTR Steering Committee composed of representatives of federal, provincial and territorial agencies.

Editing, synthesis, technical contributions, maps and graphics, and report production
by the ESTR Secretariat.

Aboriginal Traditional Knowledge
compiled from publicly available sources by D.D. Hurlburt.

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Figure 1: Overview map of the Taiga Shield Ecozone+
map
Long description for Figure 1

This map of the Taiga Shield ecozone+ shows the locations of cities/towns and bodies of water which are referred to within the report. The ecozone+ is divided into eastern and western sections by Hudson Bay. In the west, it covers most of the the eastern part of the Northwest Territories and extends across the top of Saskatchewan into the northern part of Manitoba and southern part of Nunavut. To the east of Hudson Bay, the ecozone+ extends from James Bay across Northern Quebec and Labrador to the Labrador Sea. Cities/towns shown on the map include Wekweti ,Yellowknife and Fort Smith (on the edge of the ecozone+)in the Northwest Territories, Uranium City in Saskatchewan, Shefferville in Quebec, and Labrador City on the southern edge of the ecozone+ in Labrador. Sanikiluaq on the Belcher Islands in Hudson Bay is shown, but does not fall within the ecozone. Half of Great Slave Lake falls within the western Taiga Shield and is pictured on the left side of the map, and the La Grande River is labelled in Quebec.

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Footnotes

Footnote 1

Environment Canada. 2006. Biodiversity outcomes framework for Canada. Canadian Councils of Resource Ministers. Ottawa, ON. 8 p.

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Footnote 2

Federal-Provincial-Territorial Biodiversity Working Group. 1995. Canadian biodiversity strategy: Canada's response to the Convention on Biological Diversity. Environment Canada, Biodiversity Convention Office. Ottawa, ON. 86 p.

Return to footnote 2

Footnote 3

Federal, Provincial and Territorial Governments of Canada. 2010. Canadian biodiversity: ecosystem status and trends 2010. Canadian Councils of Resource Ministers. Ottawa, ON. vi + 142 p.

Return to footnote 3

Footnote 4

Ecological Stratification Working Group. 1995. A national ecological framework for Canada. Agriculture and Agri-Food Canada, Research Branch, Centre for Land and Biological Resources Research and Environment Canada, State of the Environment Directorate, Ecozone Analysis Branch. Ottawa, ON/Hull, QC. vii + 125 p.

Return to footnote 4

Footnote 5

Rankin, R., Austin, M. and Rice, J. 2011. Ecological classification system for the ecosystem status and trends report. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 1. Canadian Councils of Resource Ministers. Ottawa, ON. ii + 14 p.

Return to footnote 5

Footnote 6

Bonsal, B. and Shabbar, A. 2011. Large-scale climate oscillations influencing Canada, 1900-2008. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 4. Canadian Councils of Resource Ministers. Ottawa, ON. iii + 15 p.

Return to footnote 6

Footnote 7

Zhang, X., Brown, R., Vincent, L., Skinner, W., Feng, Y. and Mekis, E. 2011. Canadian climate trends, 1950-2007. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 5. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 21 p.

Return to footnote 7

Footnote 8

Krezek-Hanes, C.C., Ahern, F., Cantin, A. and Flannigan, M.D. 2011. Trends in large fires in Canada, 1959-2007. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 6. Canadian Councils of Resource Ministers. Ottawa, ON. v + 48 p.

Return to footnote 8

Footnote 9

Leighton, F.A. 2011. Wildlife pathogens and diseases in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 7. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 53 p.

Return to footnote 9

Footnote 10

Fast, M., Collins, B. and Gendron, M. 2011. Trends in breeding waterfowl in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 8. Canadian Councils of Resource Ministers. Ottawa, ON. v + 37 p.

Return to footnote 10

Footnote 11

Smith, S. 2011. Trends in permafrost conditions and ecology in Northern Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 9. Canadian Councils of Resource Ministers. Ottawa, ON. iii + 22 p.

Return to footnote 11

Footnote 12

Gunn, A., Russell, D. and Eamer, J. 2011. Northern caribou population trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 10. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 71 p.

Return to footnote 12

Footnote 13

Callaghan, C., Virc, S. and Duffe, J. 2011. Woodland caribou, boreal population, trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 11. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 36 p.

Return to footnote 13

Footnote 14

Downes, C., Blancher, P. and Collins, B. 2011. Landbird trends in Canada, 1968-2006. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 12. Canadian Councils of Resource Ministers. Ottawa, ON. x + 94 p.

Return to footnote 14

Footnote 15

Gratto-Trevor, C., Morrison, R.I.G., Collins, B., Rausch, J. and Johnston, V. 2011. DO NOT USE - USE 70039 Trends in Canadian shorebirds. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 13. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 32 p.

Return to footnote 15

Footnote 16

Ahern, F., Frisk, J., Latifovic, R. and Pouliot, D. 2011. Monitoring ecosystems remotely: a selection of trends measured from satellite observations of Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 17. Canadian Councils of Resource Ministers. Ottawa, ON.

Return to footnote 16

Footnote 17

Monk, W.A. and Baird, D.J. 2011. Biodiversity in Canadian lakes and rivers. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 19. Canadian Councils of Resource Ministers. Ottawa, ON. Draft report.

Return to footnote 17

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Ecozone+ Basics

The Taiga Shield extends from the Northwest Territories to Labrador on both sides of Hudson Bay. It is a lightly-populated expanse of open forest, shrubland, tundra, and wetlands overlying the Precambrian Shield. The major localized stressor is hydroelectric development, principally on the eastern side of Hudson Bay, though there is also mining exploration and development across the ecozone+. Climate change affects the entire ecozone+.

Table 1: Taiga Shield ecozone+ overview
Area1,346,430 km2 (14% of Canada)
TopographyOpen forest dominated by small conifers, thinning to shrubland and tundra as latitude increases (Figure 2) About 13% covered by wetlands Footnote18
Climate

The climate is very different east and west of Hudson Bay, with the west being colder and drier:Footnote19

  • West: -8oC annual mean temperaturewith 200-500 mm of precipitation
  • East: 0oC annual mean temperaturewith 500-800 mm of precipitation
River basins

West of Hudson Bay, drains to:

  • Arctic Ocean via the Coppermine basin and the Mackenzie River basin
  • Hudson Bay via the Thelon, Dubawnt and other systems East of Hudson Bay drains to:
  • James and Hudson bays via the La Grande River and other systems
  • Ungava Bay
  • Atlantic Ocean
GeologyUnderlain by Precambrian Shield,with 75% of land surface covered by glacial till Most of the ecozone+is 100-600 m above sea level
PermafrostRegions of continuous and discontinuous permafrost west of Hudson Bay Sporadic permafrost through most of the Taiga Shield east of Hudson Bay
SettlementSparsely populated (42,000 in 2006), with a number of small communities (Figure 3) The largest community is Yellowknife, NT (20,000 in 2006) About 60% of population is Aboriginal
EconomyWildlife, fishing, and fur trade are important to the wage and non-wage economies of many small communities Mining, mineral exploration, hydroelectric development, and transportation, along with provision of government services, are mainstays of the wage economy
DevelopmentActive mining exploration and development for base metals, gold, diamonds Hydroelectric projects, current and projected, especially east of Hudson Bay

Jurisdictions: The Taiga Shield ecozone+ extends across the northern parts of five provinces (Newfoundland and Labrador, Quebec, Manitoba, Saskatchewan, and the northeast corner of Alberta) and two territories (southern Nunavut and a substantial part of the Northwest Territories). About 60% of the population is Aboriginal: Algonquin-based Aboriginal peoples in the east (James Bay Cree, Cree, Innu, and the Labrador Inuit), and Athapaskan-based groups (Inuit, Sahtu Dene, Akaitcho, and Tlicho) and Métis in the west. Aboriginal government structures and powers vary widely across the region, depending on the status of land claims settlements.

East-west split: The Taiga Shield ecozone+ is divided into eastern and western sections by Hudson Bay. While both parts share many characteristics, the wide geographic separation, combined with differing climatic and jurisdictional influences, means they must often be discussed separately.

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Figure 2: Major land cover classes in the Taiga Shield Ecozone+, 2005.
Land areas in urban, agricultural and snow/ice/glacier categories are very small (<0.01%) and there is no grassland. The red, "disturbed" areas are recent burn scars.
graphic
Source: Ahern et al., 2011Footnote16
Long Description for Figure 2.

This graphic depicts a map and stacked bar graph of land cover classification in the eastern and western sections of the Taiga Shield ecozone+. This ecozone+ is dominated by forest (44%) along the southern half of both the eastern and western sections, with shrubland (9%) and fire scars (8%) interspersed within the forested areas, although fire scars are more prevalent in the western section of the ecozone+. Along the northern edge of the ecozone+, low vegetation and barren ground predominates (39%), especially in the eastern Taiga Shield.

Figure 3: Human population of the Taiga Shield Ecozone+, 1971 to 2006.
Graphic
Source: Environment Canada, 2009Footnote20
Long Description for Figure 3.

This bar graph depicts the following information:

YearNumber of people
197126,165
197627,249
198130,859
198627,804
199134,029
199636,888
200138,116
200641,682

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Footnotes

Footnote 16

Ahern, F., Frisk, J., Latifovic, R. and Pouliot, D. 2011. Monitoring ecosystems remotely: a selection of trends measured from satellite observations of Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 17. Canadian Councils of Resource Ministers. Ottawa, ON.

Return to footnote 16

Footnote 18

Wiken, E., Moore, H. and Latsch, C. 2004. Peatland and wetland protected areas in Canada. Wildlife Habitat Canada Science Report. Wildlife Habitat Canada. Ottawa, ON. 18 p.

Return to footnote 18

Footnote 19

Peckham, S.D., Ahl, D.E., Serbin, S.P. and Gower, S.T. 2008. Fire-induced changes in green-up and leaf maturity of the Canadian boreal forest. Remote Sensing of Environment112:3594-3603.

Return to footnote 19

Footnote 20

Environment Canada. 2009. Unpublished analysis of population data by Ecozone+ from: Statistics Canada Human Activity and the Environment Series, 1971-2006. Community profile data was used to make adjustments due to differences in the ecozone/Ecozone+ boundary.

Return to footnote 20

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Key Findings at a Glance : National and Ecozone+ Level

Table 2 presents the national key findings from Canadian Biodiversity: Ecosystem Status and Trends 2010Footnote 3 together with a summary of the corresponding trends in the Taiga Shield Ecozone+. Topic numbers in this section refer to the national key findings in Canadian Biodiversity: Ecosystem Status and Trends 2010.Footnote 3 Topics that are greyed out were identified as key findings at a national level but were either not relevant or not assessed for this ecozone+ and do not appear in the body of this document. Evidence for the statements that appear in this table is found in the subsequent text organized by key finding. See the Preface on page i.

Table 2. Key Findings Overview

Theme: Biomes
IDTopicsKey findings: nationalKey findings: Taiga Shield Ecozone+
1ForestsAt a national level, the extent of forests has changed little since 1990; at a regional level, loss of forest extent is significant in some places. The structure of some Canadian forests, including species composition, age classes, and size of intact patches of forest, has changed over longer time frames.While there is some evidence of expansion of forests northward and up slopes in the eastern Taiga Shield, most changes observed are in structure and species composition of vegetation within the forest-tundra zone.
2GrasslandsNative grasslands have been reduced to a fraction of their original extent. Although at a slower pace, declines continue in some areas. The health of many existing grasslands has also been compromised by a variety of stressors.Not relevant
3WetlandsHigh loss of wetlands has occurred in southern Canada; loss and degradation continue due to a wide range of stressors. Some wetlands have been or are being restored.No overall trend information. Ponds are increasing in parts of Quebec and Manitoba due to melting of frozen peatlands.
4Lakes and riversTrends over the past 40 years influencing biodiversity in lakes and rivers include seasonal changes in magnitude of stream flows, increases in river and lake temperatures, decreases in lake levels, and habitat loss and fragmentation.Changes in hydrology on unmanaged streams within the Ecozone+ vary. The streams to the west of the Ecozone+ are part of the Mackenzie River Basin, which has, overall, experienced climate-related increases in streamflow, (1970-2000) while much of the drainage to the east is to Hudson and James bays, which have experienced no net change in total freshwater input (1964-2010). Major changes in the seasonal flow patterns of several rivers, especially those draining to James Bay, have resulted from dams and diversions, starting in 1973.
5CoastalCoastal ecosystems, such as estuaries, salt marshes, and mud flats, are believed to be healthy in less-developed coastal areas, although there are exceptions. In developed areas, extent and quality of coastal ecosystems are declining as a result of habitat modification, erosion, and sea-level rise.Coastlines are along James and Hudson bays, Ungava Bay, and the Atlantic Ocean. Little information on status and trends in coastal ecosystems was found for this report. The Hudson Bay region is undergoing a high rate of isostatic rebound, meaning that new soil and vegetation zones are forming. Eelgrass beds, formerly extensive along the James Bay coast, declined rapidly in the late 1990s, recovering somewhat to 2011.
6MarineObserved changes in marine biodiversity over the past 50 years have been driven by a combination of physical factors and human activities, such as oceanographic and climate variability and overexploitation. While certain marine mammals have recovered from past overharvesting, many commercial fisheries have not.Not relevant
7Ice across biomesDeclining extent and thickness of sea ice, warming and thawing of permafrost, accelerating loss of glacier mass, and shortening of lake-ice seasons are detected across Canada's biomes. Impacts, apparent now in some areas and likely to spread, include effects on species and food webs.Frozen peatlands, in the zones of sporadic and discontinuous permafrost in Quebec and Manitoba, are melting fast, with the southern boundary of permafrost landscape features in Quebec having moved north by 130 km in the past approximately 50 years.

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Theme: Human/Ecosystem Interactions
IDTopicsKey findings: NationalKey Findings: Taiga Shield Ecozone+
8Protected areasBoth the extent and representativeness of the protected areas network have increased in recent years. In many places, the area protected is well above the United Nations 10% target. It is below the target in highly developed areas and the oceans.In 2009, 7% of the Ecozone+ was protected, almost all through provincial and territorial reserves and parks.
9StewardshipStewardship activity in Canada is increasing, both in number and types of initiatives and in participation rates. The overall effectiveness of these activities in conserving and improving biodiversity and ecosystem health has not been fully assessed.Aboriginal peoples make up about 60% of the population of the Taiga Shield, and many follow traditional approaches to stewardship. These approaches vary across cultures and regions but have in common systems based on respect for animals and intimate knowledge of the land.
-Ecosystem conversionFootnote [a]Ecosystem conversion was initially identified as a nationally recurring key finding and information was subsequently compiled and assessed for the Taiga Shield Ecozone+. In the final version of the national report,3 information related to ecosystem conversion was incorporated into other key findings. This information is maintained as a separate key finding for the Taiga Shield Ecozone+.The largest land conversion in the Taiga Shield Ecozone+ has been the flooding of land for hydroelectric development in northern Quebec. For the La Grande development, since the 1970s, about 2,000 km2 of lake area and about 11,000 km2 of land were converted to reservoir. About 6,000 km2 of forest was lost due to conversion to reservoir or to land supporting infrastructure. The reservoirs underwent changes in water chemistry, plankton and fish populations, stabilizing after about 10 years. Further land conversion for hydro development is planned.
10Invasive non-native speciesInvasive non-native species are a significant stressor on ecosystem functions, processes, and structure in terrestrial, freshwater, and marine environments. This impact is increasing as numbers of invasive non-native species continue to rise and their distributions continue to expand.Limited road access and long, severe winters have kept most invasive species out of the Taiga Shield so far. A few species of birds and plants have been found, mainly near Yellowknife.
11ContaminantsConcentrations of legacy contaminants in terrestrial, freshwater, and marine systems have generally declined over the past 10 to 40 years. Concentrations of many emerging contaminants are increasing in wildlife; mercury is increasing in some wildlife in some areas.Legacy contaminants in fish in Great Slave Lake are stable or declining, although mercury has increased (1993-2008). Mercury in fish increased 3 to 8-fold following reservoir creation in the La Grande complex, peaking after 5 to 13 years and returning to background levels 10 to 35 years after flooding.
12Nutrient loading and algal bloomsInputs of nutrients to both freshwater and marine systems, particularly in urban and agriculture-dominated landscapes, have led to algal blooms that may be a nuisance and/or may be harmful. Nutrient inputs have been increasing in some places and decreasing in others.The main anthropogenic source of nutrient addition to freshwater systems has been hydroelectric development, through flooding and reservoir creation.
13Acid depositionThresholds related to ecological impact of acid deposition, including acid rain, are exceeded in some areas, acidifying emissions are increasing in some areas, and biological recovery has not kept pace with emission reductions in other areas.Not considered to be a concern for this Ecozone+
14Climate changeRising temperatures across Canada, along with changes in other climatic variables over the past 50 years, have had both direct and indirect impacts on biodiversity in terrestrial, freshwater, and marine systems.Coverage and distribution of climate trend data are poor for this Ecozone+. Temperatures showed increasing trends while precipitation trends were variable; snow cover duration decreased at the 3 stations with measurements. Most obvious ecological impacts are from changes in permafrost in the south and east of the Ecozone+, and changes in hydrology. There are indications of other impacts, for example caribou may be affected by the increase in ice content in snow.
15Ecosystem servicesCanada is well endowed with a natural environment that provides ecosystem services upon which our quality of life depends. In some areas where stressors have impaired ecosystem function, the cost of maintaining ecosystem services is high and deterioration in quantity, quality, and access to ecosystem services is evident.Provisioning services are important to cash and non-cash economies in the Taiga Shield and to cultures, nutrition and overall well-being. There are instances of deterioration of provisioning services from severe declines in caribou populations, from environmental changes affecting access to fishing and hunting, from contamination of fish by mercury, and from changes in behaviour of wildlife.

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Theme: Habitat, Wildlif, and Ecosystem Processes
IDTopicsKey Findings: NationalKey Findings: Taiga Shield Ecozone+
-Intact landscapes and waterscapesFootnote [a]Intact landscapes and waterscapes was initially identified as a nationally recurring key finding and information was subsequently compiled and assessed for the Taiga Shield ecozone+. In the final version of the national report,3 information related to intact landscapes and waterscapes was incorporated into other key findings. This information is maintained as a separate key finding for the Taiga Shield ecozone+.The Taiga Shield ecozone+ is a largely intact system. At the current rate of human activity, habitat changes are site-specific and local. However, their cumulative footprint is increasing.
16Agricultural landscapes as habitatThe potential capacity of agricultural landscapes to support wildlife in Canada has declined over the past 20 years, largely due to the intensification of agriculture and the loss of natural and semi-natural land cover.Not relevant
17Species of special economic, cultural, or ecological interestMany species of amphibians, fish, birds, and large mammals are of special economic, cultural, or ecological interest to Canadians. Some of these are declining in number and distribution, some are stable, and others are healthy or recovering.Most migratory tundra caribou herds are in decline and one herd (Bathurst) has declined severely in the last few years. Three local populations of boreal caribou in Labrador are declining. Other herds and local populations in the ecozone+ have stable or unknown trends. Some species of waterfowl are in decline in the western Taiga Shield, especially scaup (63% decline since 1970s) and American wigeon, while trends are more stable in the eastern part of the ecozone+. There have been northward range shifts in the western Taiga Shield of several species, including white-tailed deer, coyote and wood bison.
18Primary productivityPrimary productivity has increased on more than 20% of the vegetated land area of Canada over the past 20 years, as well as in some freshwater systems. The magnitude and timing of primary productivity are changing throughout the marine system.Remote sensing shows increased greening, with 36% of the land area showing a significant increase from 1986 to 2006 in NDVI, an index of primary productivity.
19Natural disturbanceThe dynamics of natural disturbance regimes, such as fire and native insect outbreaks, are changing and this is reshaping the landscape. The direction and degree of change vary.The area burned increased from the 1960s until the 1990s and declined in the 2000s. Decadal changes in area burned may be related to large-scale atmospheric oscillations. There is some indication of earlier fire seasons: an increase in May fires from none in the 1960s to 2.4% of fires in the 1990s. Little information was found on insect outbreaks, which are a less significant forest disturbance than fire in this ecozone+.
20Food websFundamental changes in relationships among species have been observed in marine, freshwater, and terrestrial environments. The loss or reduction of important components of food webs has greatly altered some ecosystems.Population cycles are a strong component of the system. Many species are migratory or at the edges of their ranges, making them vulnerable to pressures in other, more disturbed regions. There is insufficient monitoring to determine trends and to track effects of changes in one group of species on other ecosystem components.

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Theme: Science/Policy Interface
IDTopicsKey Findings: NationalKey Findings: Taiga Shield Ecozone+
21Biodiversity monitoring, research, information management, and reportingLong-term, standardized, spatially complete, and readily accessible monitoring information, complemented by ecosystem research, provides the most useful findings for policy-relevant assessments of status and trends. The lack of this type of information in many areas has hindered development of this assessment.There is little on-the-ground or long-term monitoring of physical systems in the Taiga Shield. The status of a few keystone species (for example, barren ground caribou) is monitored, but little is known about status and trends for most animal and plant species and little is known about resilience to stressors and how many aspects of the ecosystems react to change. Some specific strengths and gaps are identified.
22Rapid change and thresholdsGrowing understanding of rapid and unexpected changes, interactions, and thresholds, especially in relation to climate change, points to a need for policy that responds and adapts quickly to signals of environmental change in order to avert major and irreversible biodiversity losses.Two instances of rapid change are identified: the precipitous decline in at least one population of migratory tundra caribou and the rapid breakdown of permafrost in peatlands of the eastern Taiga Shield.

Footnote Table

Footnote[a]

This key finding is not numbered because it does not correspond to a key finding in the national report.Footnote 3

Return to reference[a]

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Footnotes

Footnote 3

Federal, Provincial and Territorial Governments of Canada. 2010. Canadian biodiversity: ecosystem status and trends 2010. Canadian Councils of Resource Ministers. Ottawa, ON. vi + 142 p.

Return to footnote 3

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Theme: Biomes

 

Forests

Key finding 1
Theme: Biomes

National key finding
At a national level, the extent of forests has changed little since 1990; at a regional level, loss of forest extent is significant in some places. The structure of some Canadian forests, including species composition, age classes, and size of intact patches of forest, has changed over longer time frames.

Forest-tundra zone

The northern boundary of the Taiga Shield is defined by the treeline – which is not a sharp line where trees end, but rather a zone of transition from increasingly sparse trees to tundra. The emerging picture for this forest-tundra zone is one of change, but not a uniform expansion of treeline.

West of Hudson Bay

The forest-tundra zone averages 145 km in width in the western Taiga Shield.Footnote21 The presence or absence of trees at points within this transition zone depends on microclimate and topography,Footnote22 as well as on past climatic conditions.Footnote23 An analysis of the treeline zone for Canada west of Hudson Bay (including the treeline zone in the Taiga Plains and Taiga Cordillera ecozones+) shows no net increase in conifers, but significant changes in other land cover types (see box).

East of Hudson Bay

In the Quebec part of the eastern Taiga Shield, trees in the forest-tundra zone have grown faster and taller since the 1970sFootnote24 but distribution of trees has not changed greatly,Footnote25 although white spruce has recently (over the past 50 years) expanded along the east coast of Hudson Bay.Footnote26 In Labrador, treelines have expanded northward and up slopes over the past 50 years along the coast, but not inland.Footnote27

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The forest-tundra zone west of Hudson Bay
Figure 4: Vegetation changes in the treeline zone, west of Hudson Bay 1985-2006

Mean change over 22 years based on analysis of early spring and summer satellite images. The inset map, adapted from Olthof and Pouliot, 2010,Footnote28 shows the area analysed.
graph
Source: data from Olthof and Pouliot, 2010Footnote28
Long Description for Figure 4.

This graph shows the following information:

-Mean percent change
Bare-0.094
Lichen-0.039
Conifer0.005
Herb0.124
Shrub0.150

The inset map depicts the area analysed in the study, which extends along the treeline zone from the northern part of the Yukon across the Northwest Territories and into the southeastern Nunavut/northern Manitoba.

A study using satellite imagery to look at recent trends along the treeline zone west of Hudson Bay found only a small net increase in tree cover, but major changes in vegetation cover (Figure 4).Footnote28 Tree cover increased in the northern half of the zone, but this was mainly offset by decreases in the southern half. The changes were more pronounced to the west of the Taiga Shield, especially west of the Mackenzie Delta, likely related to drier conditions due to the marked warming trends in these regions.Footnote29 The biggest changes were an increase in shrubs and, in the northwest of the treeline zone, a replacement of lichen cover and bare land with small, non-woody plants (herbs).

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Wetlands

Key finding 3
Theme: Biomes

National key finding
High loss of wetlands has occurred in southern Canada; loss and degradation continue due to a wide range of stressors. Some wetlands have been or are being restored.

Wetlands cover roughly 13% of the surface area of the Taiga Shield, Footnote18 and trends in the total wetlands area are unknown. Ponds are increasing in parts of Quebec and Manitoba, and probably elsewhere in the Ecozone+ due to melting of frozen peatlands (see Permafrost trends on page 17). This wetland expansion is related to changes in temperature and precipitation patterns. Some reduction of wetlands area has resulted from hydroelectric developments in northern Quebec (see Ecosystem Conversion on page 23). Among the documented changes associated with hydroelectricity development east of James Bay is a reduction in the area of string bogs (narrow, low ridges with wet depressions or pools) in Quebec's Lake Plateau area. These wetlands provide habitat for shorebirds and bald eagles.Footnote30 Both the James Bay (Quebec)Footnote31 and Churchill River (Newfoundland and Labrador)Footnote32 hydro projects will be expanded in the next few years-including development of two substantial reservoirs and diversion of half the flow of the Rupert River-which is likely to have a further impact on wetlands in the eastern Taiga Shield.

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Lakes and Rivers

Key finding 4
Theme: Biomes

National key finding
Trends over the past 40 years influencing biodiversity in lakes and rivers include seasonal changes in magnitude of stream flows, increases in river and lake temperatures, decreases in lake levels, and habitat loss and fragmentation.

Changes in hydrology on unmanaged streams within the Ecozone+ vary. The streams to the west of the Ecozone+ are part of the Mackenzie River Basin, which has, overall, experienced climate-related increases in streamflow, (1970-2000) while much of the drainage to the east is to Hudson and James bays, which have experienced no net change in total freshwater input (1964-2010). Major changes in the seasonal flow patterns of several rivers, especially those draining to James Bay, have resulted from dams and diversions, starting in 1973.

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Regional trends

Large-scale trends relevant to the Taiga Shield Ecozone+ are:
Mackenzie River Basin: increase in annual winter flows and in annual minimum flows from 1970 to 2000, and earlier spring peak flows. Flows in early summer and late fall, as well as the annual mean flow, decreased slightly. The trends correlate with warmer winters and springs, less winter snow, and more spring rain.Footnote33 Hudson Bay watershed: discharge declined from the mid-1960s to the mid-1980s, followed by a period of relatively high flows and an upward trend (Figure 5). It is unclear to what degree these trends are related to climate change and/or decadal climate oscillations.Footnote34 While there was no trend in total discharge over the entire period, streamflow increased in the winter and decreased in the summer from 1964 to 2008. This seasonal shift is attributed to the strong influence of increasing flow regulation in this watershed: water stored in spring and summer is released in the winter for power generation.Footnote34

Figure 5: Total annual discharge into Hudson and James bays, 1964-2010.

Total discharge is estimated based on records from 23 rivers, including the regulated La Grande Rivière.
Graph
Source: Déry et al., 2011Footnote34 with 2009 and 2010 data provided by S.J. Déry
Long Description for Figure 5.

This line graph shows the following information:

YearTotal discharge (km3)
1964518
1965544
1966605
1967527
1968578
1969601
1970542
1971527
1972493
1973493
1974558
1975529
1976456
1977486
1978515
1979591
1980454
1981410
1982463
1983507
1984490
1985561
1986545
1987488
1988489
1989446
1990473
1991450
1992532
1993498
1994493
1995507
1996525
1997554
1998475
1999530
2000546
2001526
2002548
2003485
2004551
2005635
2006550
2007592
2008616
2008603
2009631
2010498

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Trends within the ecozone+: streams with natural flow regimes

This section is based on Canada-wide analyses performed by Cannon et al. 2011Footnote35 for the 2010 Ecosystem Status and Trends Report.

Within both eastern and western parts of the Taiga Shield, hydrometric records are sparse and often too short to detect trends. Only two stations (Camsell River, NWT, and Seal River, Manitoba) – both in the western Taiga Shield – have adequate stream discharge and climate records (1961-2003) to examine trends over the annual cycle.Footnote35 Both of these streams showed significant streamflow increases throughout the year, with the exception of spring (streamflow for Camsell River is shown in Figure 6). These changes could be due to a combination of the increased precipitation coupled with the warmer winters and springs recorded in the vicinity of the streams.Footnote35

Figure 6: Streamflow change at Camsell River, 1961-1982 compared with 1983-2003

Streamflow change at Camsell River, 1961-1982 compared with 1983-2003. Streamflow was analyzed in 5-day periods, comparing 73 periods over the annual cycle.
graph
Source: Cannon et al., 2011Footnote35
Long Description for Figure 6

A graph comparing streamflow in the Camsell River shows that recent years (1983-2003) have experienced higher streamflow than previous years (1961-1982). Streamflow has been significantly higher through most of the year, except in the spring (May and June). The data is taken from a gauging station on the Camsell River in the Northwest Territories and the analyzed in 5 day periods, comparing 73 periods over an annual cycle.

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Trends within the ecozone+: streams with managed flow regimes

Several major hydroelectricity developments, mainly in the eastern part of the ecozone+, have altered flow regimes since the 1970s. The La Grande (James Bay) hydroelectric development in Quebec has resulted in dramatic changes to some rivers in the eastern Taiga Shield. The complex was constructed in two phases, the first one during 1973-1985 and the second one during 1987-1996. Three main rivers were diverted into La Grande River: the Eastmain, Opinaca, and Caniapiscau. As a result of these diversions, the mean annual flow of La Grande River at its mouth doubled and its mean winter flow increased more than tenfold.Footnote30

Main impacts from these diversions include changes to estuarine, coastal and marine systems from the increased under-ice freshwater plume of La Grande RiverFootnote36 (see Coastal on page 15).

Fishing yields fluctuated after diversions were put in place, but, overall, yields stabilized at levels above or close to those found under natural conditions.Footnote37 In general, fish species composition and growth rates in the reduced-flow rivers were similar before and after the flow reductions.

Changes to fish populations in rivers with altered flow include:

  • La Grande River: displacement of species that are not tolerant of cold water – walleye (Sander viterus) and cisco (Coregonus sp.) – by cold-water tolerant species – round whitefish (Prosopium cylindraceum) and brook trout (Salvelinus fontinalis).Footnote37 Mean maximum summer water temperatures in the river were lowered from 16°C to 8°C following development.Footnote37
  • Eastmain River: lake sturgeon (Acipenser fulvescens) numbers declined, related to flow reduction and habitat fragmentation by weirs.Footnote37, Footnote38 Fishing pressure may also have been a factor in this decline.Footnote37, Footnote38 The James Bay population of lake sturgeon was assessed as being of Special Concern by COSEWIC in 2005, confirmed in 2006,Footnote38 citing declines in habitat and possibly abundance, related to existing and projected hydroelectric development.

Changes affecting fish in the reservoirs are discussed under Dams and reservoirs on page 28.

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Coastal

Key finding 5
Theme: Biomes

National key finding
Coastal ecosystems, such as estuaries, salt marshes, and mud flats, are believed to be healthy in less-developed coastal areas, although there are exceptions. In developed areas, extent and quality of coastal ecosystems are declining as a result of habitat modification, erosion, and sea-level rise.

The eastern Taiga Shield Ecozone+ has coastlines along James and Hudson Bays, Ungava Bay, and the Atlantic Ocean. Little information on status and trends in coastal ecosystems was found for this report. The James and Hudson bays region is undergoing a high rate of isostatic rebound, meaning that new soil and vegetation zones are forming. Eelgrass beds, formerly extensive along the James Bay coast, declined rapidly in the late 1990s, recovering somewhat to 2011. Footnote39

A severe reduction in eelgrass (Zostera marina) along the James Bay coast was reported by Cree residents of the region in 1998; this decline was also detected in monitoring conducted by Hydro Québec. Footnote40 By 2004, monitoring indicated that some recovery had taken place, confirmed by further monitoring in 2009 (Figure 7)Footnote41 and 2011. Footnote39

Eelgrass beds were among the most extensive in North America, distributed all along the east coast of James Bay, covering 250 km2, and found at depths of 0.5 to 4 mFootnote42 prior to their rapid decline in density and biomass around 1998 (Figure 7). Eelgrass in James Bay provides shelter for small fish and invertebrates and is important food and habitat for migrating and wintering waterfowl, Canada geese (Branta canadensis) and Brant geese (Branta bernicla) in particular, and provides foraging areas for Arctic terns.Footnote43 Footnote44 Footnote45 Eelgrass distribution and growth are influenced by salinity;Footnote45 low salinity or high temperatures can make eelgrass vulnerable to disease.Footnote43

Figure 7: Decline of eelgrass in James Bay: example of monitoring results for leaf biomass and shoot density, Kakassituq station, 1988-2009.

Samples were taken at several depths at 6 sites – this figure shows results typical at all depths for 5 of the 6 sites. The 6th site (Dead Duck Bay, the station furthest to the south of the La Grande River mouth) showed no change.
Graph
Source: GENIVAR, 2009Footnote41
Long Description for Figure 7.

Three bar graphs showing the following information:

a) 0.5 m
YearMean dry biomass (g/m2)Mean number of shoots (N/m2)
1988194983
19892631,641
1990234836
1991189931
19933821,737
19943541,039
19954561,751
1999737
2000656
200936292
b) 1.0 m
YearMean dry biomass (g/m2)Mean number of shoots (N/m2)
1988472689
1989358880
1990272578
1991294699
1993415887
1994295665
19955591,108
19991843
20001272
2009112429
c) 1.5 m
YearMean dry biomass (g/m2)Mean number of shoots (N/m2)
1988399512
1989387833
1990317516
1991392757
1993361787
1994298617
1995548948
19996375
2000840
2009124409

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Explanations advanced for the decline include:

  1. a disease outbreak triggered by unusually high summer and winter temperatures, along with changes in the coast from isostatic rebound and other changes related to a warming climate;Footnote40
  2. impaired growth and survival due to reduced salinity of water in James Bay resulting from larger and more frequent discharges of fresh water via the La Grande River (due to diversions, see Dams and diversions, page 25).Footnote45

As of 2011, vast eelgrass beds can be seen at various locations along James Bay. Distribution and abundance of eelgrass has not recovered to pre-decline levels, however, and recovery is not uniform along the coast.Footnote39

Ice across biomes

Key finding 7
Theme: Biomes

National key finding
Declining extent and thickness of sea ice, warming and thawing of permafrost, accelerating loss of glacier mass, and shortening of lake-ice seasons are detected across Canada's biomes. Impacts, apparent now in some areas and likely to spread, include effects on species and food webs.

Lake ice trends

An analysis of seven large lakes in or at the edges of the ecozone+, between 1970 and 2004, showed variable trends in timing of freeze-up and ice break-up, with few changes being statistically significant.Footnote46 National trends are towards an earlier break-up of lake ice, with less consistent trends in freeze-up timing (1960s or 1970s to 1990s, when most lake ice monitoring was discontinued).Footnote17

Permafrost trends

Permafrost is thawing at a rapid rate in the eastern Taiga Shield, resulting in a change in the landscape from dry, lichen-heath ecosystems supporting black spruce trees and dotted with ponds to wetter landscapes with ponds, and characterized by fen and bog vegetation.Footnote47-Footnote49 As well as altering habitats, these changes affect carbon flux as the thawing of peat and formation of ponds releases carbon to the atmosphere, while the subsequent transition to fen/bog vegetation stores carbon. Permafrost is also degrading in peatlands in northern Manitoba (based on field investigations over the latter half of the 20th century).Footnote50 This trend is likely becoming more widespread in the western Taiga Shield as well, although data are not available.

Broad-scale permafrost distribution in the Taiga Shield ecozone+ differs between east and west of Hudson Bay, with the east having less extensive permafrost (Figure 8). In the eastern Taiga Shield, the sporadic permafrost zone is characterized by frozen peat plateaus and palsas (mounds of peat or soil containing ice lenses). Formation and degradation of these permafrost landforms are influenced by air temperature and by insulation from snow cover and from peat.Footnote47 When the permafrost is degraded, the resulting melted ice forms ponds (called thermokarst ponds).

Figure 8: Permafrost distribution, Taiga Shield ecozone+.
Map
Source: adapted from Smith, 2011Footnote11
Long Description for Figure 8.

This map shows the distribution of permafrost zones in northern Canada and highlights the differences in permafrost in the eastern and western parts of the Taiga Shield Ecozone+. The eastern section is dominated by sporadic permafrost, with only a small area of extensive discontinuous permafrost in the north. In contrast, in the west, only areas in the south of the ecozone+ (sections in Alberta, Saskatchewan and Manitoba) are classified as sporadic permafrost; discontinuous permafrost and continuous permafrost dominate in the western Taiga Shield.

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Three studies in Quebec show the extent of change in permafrost in the past 50 years (summarized in Figure 9).

  1. A study mapping palsas and thermokarst ponds along the Boniface River in the discontinuous permafrost zone at the northern edge of the ecozone+ (site A, Figure 9)Footnote47 found that the area occupied by palsas decreased by 23% between 1957 and 2001, while 76% of present-day thermokarst pond area had formed since 1957. No new palsas developed along the river during this period. Permafrost degradation was most severe close to the river where water fluctuations had a strong influence.
  2. A study mapping change in a peatland east of Hudson Bay (site B, Figure 9)Footnote48 found that the area was mainly frozen in 1957, with about 18% of the surface covered in thermokarst ponds. Palsa mounds, being well-drained, supported growth of lichens and black spruce trees. By 2003 only 13% of the surface area remained as permafrost, with the remainder being a mix of thermokarst ponds and fen/bog vegetation (sedges and Sphagnum moss). Fen/bog vegetation was virtually absent in 1957 but covered half the study area by 2003. Spruce trees died as the permafrost decayed and their roots became flooded. The annual rate of permafrost degradation approximately doubled in the last decade of the study to -5.3% per year; this acceleration in melt rate was likely related to increasing trends in summer temperatures and precipitation since the mid-1990s.
  3. A survey over a broad area of the James Bay regionFootnote49 showed that changes documented at the above sites are widespread. The landscape in the zone of sporadic permafrost is in transition from dry, lichen-covered palsas interspersed with ponds to a wetter ecosystem dominated by larger ponds, bogs and fens. The southern limit of permafrost has moved about 130 km north, mainly within about the past 50 years. North of the current permafrost boundary (in the vicinity of "C" on Figure 9), permafrost is in an advanced state of degradation – palsas in bogs observed and surveyed in this region up to 2004 had shrunk or disappeared by 2005.

Lichens, important forage for caribou (Rangifer tarandus), are maintained in the James Bay area by periodic fire and by permafrost – both of which create dry micro-environments. If, as seems likely, the permafrost continues to degrade and disappears within a few years, the resulting wetter bog ecosystems will lead to widespread declines in lichen.Footnote49

Figure 9: Change in permafrost landforms, thermokarst ponds and extent in permafrost in three studies in northern Quebec.

Studies A and B are based on ground surveys and 1957 air photos.
Study C involved helicopter surveys along two 350 km north-south transects conducted in 2004 and 2005. These were supplemented with ground surveys, defined the northern extent of permafrost by the presence of palsas and the southern extent of thermokarst ponds (the latter indicating the presence of permafrost within about the past 50 years). "C" indicates the approximate location of palsa/thermokarst pond study sites.
Map
Source: Study A. Vallée and Payette, 2007;Footnote47 Study B. Payette et al., 2004;Footnote48 and Study C. Thibault and Payette, 2009Footnote49
Long Description for Figure 9.

This figure includes a map and two graphs documenting changes in the total area, land cover, and permafrost limits in three studies from northern Quebec. The bar graph on the top left depicts a 23% decrease in the total area of palsas (mounds of peat or soil containing ice lenses) and a 76% increase in pond area between 1957 and 2001; the location of the study site is indicated on the map at point "A", along the Boniface River. The line graph on the top right shows the following information:

Yearpermafrostpondsfen
195782%18%0%
198338%32%28%
199328%30%42%
200313%37%50%

In addition to showing the locations of the three studies, the map at the bottom also depicts a 130 km northward change in the southern permafrost limit, documented in a more recent study (study "C", 2004 and 2005), which defined the southern extent of areas which were formerly permafrost by the presence of thermokarst ponds.

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Footnotes

Footnote 11

Smith, S. 2011. Trends in permafrost conditions and ecology in Northern Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 9. Canadian Councils of Resource Ministers. Ottawa, ON. iii + 22 p.

Return to footnote 11

Footnote 17

Monk, W.A. and Baird, D.J. 2011. Biodiversity in Canadian lakes and rivers. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 19. Canadian Councils of Resource Ministers. Ottawa, ON. Draft report.

Return to footnote 17

Footnote 18

Wiken, E., Moore, H. and Latsch, C. 2004. Peatland and wetland protected areas in Canada. Wildlife Habitat Canada Science Report. Wildlife Habitat Canada. Ottawa, ON. 18 p.

Return to footnote 18

Footnote 21

Timoney, K.P., Roi, G.H.L., Zoltai, S.C. and Robinson, A.G. 1992. The high Subarctic forest-tundra of northwestern Canada: position, width, and vegetation gradients in relation to climate. Arctic45:1-9.

Return to footnote 21

Footnote 22

Timoney, K.P. 1995. Tree and tundra cover anomalies in the Subarctic forest-tundra of northwestern Canada. Arctic48:13-21.

Return to footnote 22

Footnote 23

Nichols, H. 1976. Historical aspects of the northern Canadian treeline. Arctic29:38-47.

Return to footnote 23

Footnote 24

Gamache, I. and Payette, S. 2004. Height growth response of tree line black spruce to recent climate warming across the forest-tundra of eastern Canada. Journal of Ecology92:835-845.

Return to footnote 24

Footnote 25

Gamache, I. and Payette, S. 2005. Latitudinal response of Subarctic tree lines to recent climate change in eastern Canada. Journal of Biogeography32:849-862.

Return to footnote 25

Footnote 26

Laliberte, A.C. and Payette, S. 2008. Primary succession of Subarctic vegetation and soil on the fast-rising coast of eastern Hudson Bay, Canada. Journal of Biogeography35:1989-1999.

Return to footnote 26

Footnote 27

Payette, S. 2007. Contrasted dynamics of northern Labrador tree lines caused by climate change and migrational lag. Ecology88:770-780.

Return to footnote 27

Footnote 28

Olthof, I. and Pouliot, D. 2010. Treeline vegetation composition and change in Canada's western Subarctic from AVHRR and canopy reflectance modeling. Remote Sensing of Environment114:805-815.

Return to footnote 28

Footnote 29

Pisaric, M.F.J., Carey, S.K., Kokelj, S.V. and Youngblut, D. 2007. Anomalous 20th century tree growth, Mackenzie Delta, Northwest Territories, Canada. Geophysical Research Letters34, L05714, 5 p..

Return to footnote 29

Footnote 30

Hayeur, G. 2001. Summary of knowledge acquired in northern environments from 1970 to 2000. Hydro-Québec. Montréal, QC. x + 110 p. .

Return to footnote 30

Footnote 31

Hydro-Québec. 2010. Eastmain-1-A/Sarcelle/Rupert project [online]. Hydro-Québec. (accessed December, 2010).

Return to footnote 31

Footnote 32

Nalcor Energy and Government of Newfoundland and Labrador. 2011. Report of the Joint Review Panel -- Lower Churchill hydroelectric generation project. Government of Canada and Government of Newfoundland and Labrador. Ottawa, ON and St. John's, NL. 355 p.

Return to footnote 32

Footnote 33

Abdul Aziz, O.I. and Burn, D.H. 2006. Trends and variability in the hydrological regime of the Mackenzie River Basin. Journal of Hydrology319:282-294.

Return to footnote 33

Footnote 34

Déry, S.J., Mlynowski, T.J., Hernández-Henríquez, M.A. and Straneo, F. 2011. Interannual variability and interdecadal trends in Hudson Bay streamflow. Journal of Marine Systems88:341-351-.

Return to footnote 34

Footnote 35

Cannon, A., Lai, T. and Whitfield, P. 2011. Climate-driven trends in Canadian streamflow, 1961-2003. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 19. Canadian Councils of Resource Ministers. Ottawa, ON. Draft report.

Return to footnote 35

Footnote 36

Hydro-Québec and GENIVAR Groupe Conseil inc. 2005. Environmental monitoring of the La Grande-2-A and La Grande-1 projects: abridged summary report 1987-2000: La Grande Rivière winter plume. Joint report by Hydro-Québec and GENIVAR Groupe Conseil Inc. 27 p. + appendix.

Return to footnote 36

Footnote 37

Therrien, J., Verdon, R. and Lalumière, R. 2004. Environmental monitoring at the La Grande complex. Changes in fish communities. Summary report 1977-2000. GENIVAR Groupe Conseil Inc. and Direction Barrages et Environnement, Hydro-Québec Production. 129 p. + appendices.

Return to footnote 37

Footnote 38

COSEWIC. 2006. COSEWIC assessment and update status report on the lake sturgeon Acipenser fulvescens in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa, ON. xi + 107 p.

Return to footnote 38

Footnote 39

Consortium Waska-GENIVAR. 2011. Centrales de l'Eastmain-1-A et de la Sarcelle et dérivation Rupert. Suivi de la zostère marine de la côte nord-est de la baie James. Rapport d'étude 2011. Rapport du Consortium Waska-GENIVAR inc. pour Hydro-Québec Production. 57 p.  + appendices.

Return to footnote 39

Footnote 40

Hydro-Québec and GENIVAR Groupe Conseil inc. 2005. Environmental monitoring at the La Grande complex: abridged summary report 1988-2000: eelgrass meadows of the northeast coast of James Bay. Joint report by Hydro-Québec and GENIVAR Groupe Conseil Inc. 42 p. + appendices.

Return to footnote 40

Footnote 41

GENIVAR. 2010. Centrales de l'Eastmain-1-A et de la Sarcelle et dérivation Rupert. Suivi de la zostère marine de la côte nord-est de la baie James. État de référence 2009. Rapport de GENIVAR Société en commandite pour Hydro-Québec et la Société d'énergie de la Baie James. 54 p. + appendices.

Return to footnote 41

Footnote 42

Lalumière, R., Messier, D., Fournier, J.J. and Mcroy, C.P. 1994. Eelgrass meadows in a low Arctic environment, the northeast coast of James Bay, Quebec. Aquatic Botany47:303-315.

Return to footnote 42

Footnote 43

Standing Committee on Fisheries and Oceans. 2008. Fifth report of the Standing Committee on Fisheries and Oceans to the House of Commons. Government of Canada. Ottawa, ON. 2 p.

Return to footnote 43

Footnote 44

Hanson, A.R. 2004. Status and conservation of eelgrass (Zostera marina) in eastern Canada. Technical Report Series No. 412. Environment Canada, Canadian Wildlife Service, Atlantic Region. Sackville, NB. 40 p.

Return to footnote 44

Footnote 45

Short, F.T. 2008. Report to the Cree Nation of Chisasibi on the status of eelgrass in James Bay. Jackson Estuarine Laboratory. Durham, NH. 30 p.

Return to footnote 45

Footnote 46

Latifovic, R. and Pouliot, D. 2007. Analysis of climate change impacts on lake ice phenology in Canada using the historical satellite record. Remote Sensing of Environment106:492-507.

Return to footnote 46

Footnote 47

Vallée, S. and Payette, S. 2007. Collapse of permafrost mounds along a Subarctic river over the last 100 years (northern Québec). Geomorphology90:162-170.

Return to footnote 47

Footnote 48

Payette, S., Delwaide, A., Caccianiga, M. and Beauchemin, M. 2004. Accelerated thawing of Subarctic peatland permafrost over the last 50 years. Geophysical Research Letters31:1-4.

Return to footnote 48

Footnote 49

Thibault, S. and Payette, S. 2009. Recent permafrost degradation in bogs of the James Bay area, northern Quebec, Canada. Permafrost and Periglacial Processes20:383-389.

Return to footnote 49

Footnote 50

Camill, P. 2005. Permafrost thaw accelerates in boreal peatlands during late-20th century climate warming. Climatic Change 68:135-152.

Return to footnote 50

Return to Table of Contents

Theme: Human/Ecosystem Interactions

 

Protected areas

Key finding 8
Theme: Human/ecosystem interactions

National key finding
Both the extent and representativeness of the protected areas network have increased in recent years. In many places, the area protected is well above the United Nations 10% target. It is below the target in highly developed areas and the oceans.

Prior to 1992 (the signing of the Convention on Biological Diversity), 1.1% of the Taiga Shield ecozone+ was protected. This was increased to 7.0% of the ecozone+ by May 2009 (Figure 10 and Figure 11), broken down as follows:

  • 5.2% (29 protected areas) as IUCN(International Union for Conservation of Nature) categories I-III. These categories include nature reserves, wilderness areas, and other parks and reserves managed for conservation of ecosystems and natural and cultural featuresFootnote51
  • 0.5% (three protected areas) as IUCN category V, a category that focuses on sustainable use by established cultural traditionFootnote51
  • 1.4% (five protected areas established since 2005) not classified by IUCN category
Figure 10: Growth of protected areas, Taiga Shield ecozone+, 1922-2009.
Data provided by federal, territorial and provincial jurisdictions, updated to May 2009. Only legally protected areas are included. IUCN (International Union for Conservation of Nature) categories of protected areas are based on primary management objectives (see text for more information). There are no Category IV protected areas in the ecozone+. Note: the grey "unclassified" category represents protected areas for which the IUCN category was not provided. The last bar labelled "TOTAL" includes protected areas for which the year established was not provided.
Graph
Source: Environment Canada, 2009,Footnote 52 data from the Conservation Areas Reporting and Tracking System (CARTS), v.2009.05 Footnote 53
Long Description for Figure 10.

This bar graph shows the following information:

YearIUCN Categories I-III (km2)IUCN Category V (km2)Unclassified (km2)
1922-192616200
1927-198614,39400
1987-198814,42200
1989-199414,81800
1995-199734,14600
199835,07000
1999-200135,15200
200251,06300
2003-200454,33300
2005-200754,354024
200863,036016,501
200969,508018,295
Total69,5126,06018,295

Thelon Wildlife Sanctuary was created in 1927, Numaykoos Lake, Caribou River, and Sand Lakes Provincial Parks (Manitoba) in 1995 and Lacs-Guillaume-Delisle-et-l'Eau-Claire National Park Reserve (Quebec) in 2002.

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Figure 11: Map of the Taiga Shield ecozone+ protected areas, May 2009.
Map
Source: Environment Canada, 2009,Footnote 52 data from the Conservation Areas Reporting and Tracking System (CARTS), v.2009.05 Footnote 53
Long Description for Figure 11.

This map shows the locations of protected land in the eastern and western section of the Taiga Shield Ecozone+ as of May 2009. Protected areas are generally evenly distributed between the eastern and western parts of the ecozone+.

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Stewardship

Key finding 9
Theme: Human/ecosystem interactions

National key finding
Stewardship activity in Canada is increasing, both in number and types of initiatives and in participation rates. The overall effectiveness of these activities in conserving and improving biodiversity and ecosystem health has not been fully assessed.

Many Aboriginal people of the Taiga Shield continue to live off the land, in whole or in part, as their ancestors did, and they retain traditional stewardship approaches to the land and wildlife. For example, the Aboriginal peoples of the Taiga Shield observe heightened respect for caribou, a value embedded in spiritual beliefs and customs.54 Many Dene elders attribute the absence of caribou in some years to a lack of respect shown for the land and animals. Good hunting practices and proper harvesting and preservation of meat are some ways to demonstrate this respect.Footnote 54 Footnote 55 Footnote 56

The Cree have a customary land-tenure system that ensures the continuity of resources vital to the local subsistence economy. Tallymen or "hunting bosses" act as stewards for hunting grounds under their responsibility and oversee both hunting and trapping on those hunting grounds.Footnote 57

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Traditional stewardship and science

Traditional approaches to stewardship and the land can occasionally come into conflict with scientific approaches. Many Aboriginal elders consider some contemporary wildlife management techniques, especially capture and handling, disrespectful to the animals.Footnote 58 Footnote 59 Footnote 60 For example, 80% of Dene elders involved in a set of interviews disagreed with the practice of tracking caribou with radio-collars.Footnote 61

 

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Ecosystem conversion

Theme: Human/ecosystem interactions

Ecosystem conversion was initially identified as a nationally recurring key finding and information was subsequently compiled and assessed for the Taiga Shield Ecozone+. In the final version of the national report,Footnote 3 information related to ecosystem conversion was incorporated into other key findings. This information is maintained as a separate key finding for the Taiga Shield Ecozone+.

The largest land conversion in the Taiga Shield ecozone+ is the flooding of land for hydroelectric development in northern Quebec.

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Dams and reservoirs

Churchill Falls in Labrador and the La Grande (James Bay) complex in Quebec have flooded about 14,150 km2 of landFootnote 30, enlarging existing water bodies and creating large reservoirs. The La Grande complex (Figure 12) created eight reservoirs, filled between 1979 and 1993, ranging from 70 to 4,275 km2 in size. Areas converted from natural lakes to reservoirs, land area flooded, and area deforested (due to reservoirs and infrastructure) are shown in Figure 13. A third project, the Churchill-Nelson development in Manitoba, straddles the Taiga Shield, Hudson Plains, and Boreal Shield ecozones+. Other, smaller hydro projects in the Taiga Shield do not involve reservoirs or river diversions. The majority (88%) of the 177 dams completed in the ecozone+ were built between 1970 and 1990.Footnote 17

Figure 12: La Grande hydroelectric complex
map
Source: Hayeur, 2001Footnote 30
Long Description for Figure 12.

This map shows the hydroelectric infrastructure of the La Grande hydroelectric complex. The map depicts the series of reservoirs, dams, hydroelectric generating stations, roads, and transmission lines in the complex, as well as village locations. From east to west, the Caniapiscau, Laforge, La Grande, Robert-Bourassa, and Opinaca reservoirs are pictured. Major transmission lines extend south from generating stations on Robert-Bourassa and La Grande 3 and 4. The inset map in the bottom right shows the location of the La Grande complex in central Quebec.

 

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Figure 13: Cumulative area affected by hydro development in La Grande Complex, James Bay, 1970-2005
The total land area flooded is about half the size of Lake Winnipeg, or double the size of Prince Edward Island. Deforested area is land that was covered by trees at least 5 m tall, with a crown closure of 25% before inundation. Landsat imagery and aerial photography were used for the analysis.
Bar and line graph
Source: CFS deforestation statistics from Leckie et al., 2006;Footnote 62 total land area and total lake area converted to reservoir from Hayeur, 2001Footnote 30
Long Description for Figure 13.

This bar and line graph presents the following information:

Area (km2, cumulative)
YearLand area converted to reservoirLake area converted to reservoirArea deforested
1970--13
1971--27
1972--40
1973--50
1974--64
1975--78
1976--93
1977--111
1978--758
19792,6302051,613
19803,3705051,636
19813,3705053,448
19823,3705053,943
19834,0705705,079
19849,8461,7575,153
19859,8461,7575,162
19869,8461,7575,171
19879,8461,7575,180
19889,8461,7575,188
19899,8461,7575,207
19909,8461,7575,224
19919,8461,7575,260
19929,8461,7575,301
199310,8092,1525,658
199410,8092,1525,665
199510,8092,1525,673
199610,8092,1525,683
199710,8092,1525,694
199810,8092,1525,733
199910,8092,1525,794
200010,8092,1525,802
200110,8092,1525,809
200210,8092,1525,905
200310,8092,1525,921
200410,8092,1525,947
200510,8092,1525,983

Future major projects planned for the eastern Taiga Shield include the Lower Churchill development, with two reservoirs totalling 300 km2 and associated dams and power lines,32 and the next phase of the James Bay project, involving diversion of half the annual flow of the Rupert River and construction of a 600 km2 reservoir.Footnote 63

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Ecological change in La Grande project reservoirs

Reservoir creation caused a number of physical changes: rapid increase in water surface area, volume and residence time; change from river to lake conditions in flooded sections of rivers; mixing of waters from different watersheds; changes in flood cycles; changes in freezing and thawing timing; and reduced surface water temperatures.Footnote 37

Models based on data from the reservoirs of the La Grande complex indicate that reservoir creation has a net effect of increasing carbon (CO2 and methane) emissions to the atmosphere on a long-term basis, mainly due to the increase in the length of time water is stored (an increase of about two years for the Robert-Bourassa reservoir).Footnote 64 This increase in storage time increases emissions from organic matter present in the water column. Globally, reservoirs are estimated to account for 4% of anthropogenic CO2 emissions.Footnote 64

Highlights of results of a comprehensive program of freshwater aquatic ecological monitoring related to the La Grande reservoirs, undertaken by Hydro-Québec, 1977-2000,Footnote 30 are presented below.

Water quality

Changes in physical and chemical characteristics of the reservoirs peaked within two to three years of filling, while remaining within ranges favourable to biological productivity (Figure 14). The greatest changes occurred in late winter, under ice, with the formation of deep-water zones with low oxygen. After 9 to 10 years, the main parameters had returned to or approached pre-construction levels in the Opinaca and Robert-Bourassa reservoirs, while this cycle, especially for phosphorus and silica, occurred more slowly in the Caniapiscau reservoir

Figure 14. Changes over the first decade of impoundment in water chemistry parameters linked with the decomposition of submerged organic matter, La Grande complex reservoirs
Measurements are in the zone exposed to sunlight (top about 10 m) during the ice-free period.
Graphic
Source: Hayeur, 2001Footnote 30
Long Description for Figure 14.

This set of 6 line graphs shows the change in water chemistry parameters related to submerged organic matter two years before and ten years after reservoir creation. The parameters include dissolved oxygen (% saturation), pH, total inorganic carbon (mg/L), total phosphorus (µg/L-1 of P), Chlorophyll-a (µg/L), and silica (mg/L-1). Data is from three reservoirs (Opinaca, Robert-Bourassa, and Caniapiscau) and measurements were taken in the top 10 m of water during the ice-free period. All parameters show substantial variation in the first five years after impoundment, but within the decade most parameters were fairly similar to the pre-impoundment level, except that total inorganic carbon increased slightly in all reservoirs. Most parameters showed similar patterns in Opinaca and Robert-Bourassa reservoirs, but the parameters in Caniapiscau showed different trends in some cases, including a greater increase total phosphorus and chlorophyll-α, and generally lower silica measurements.

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Plankton and benthos

Apart from creating new aquatic environments, the flooding changed planktonic and benthic ecosystems - some on a short-term basis, and some apparently permanently.

  • Phytoplankton levels, tracked through measurement of chlorophyll-a (Figure 14), rose rapidly from the time of impoundment, then declined and stabilized at levels comparable to natural values. Increases in primary productivity are attributed mainly to the increase in phosphorus.
  • Zooplankton abundance and biomass increased in all reservoirs as a result of the increase in nutrients and in organic matter produced by the decomposition of flooded plants (Figure 15). The cycle of change tracked changes in water quality and phytoplankton, with a lag of about a year.
  • Benthic communities experienced shifts in species. Diversity declined after impoundment, due to the loss of less mobile species and of species adapted to fast-running water. The reservoirs were rapidly colonized by lake-dwelling species.
Figure 15. Changes in zooplankton biomass: Robert-Bourassa reservoir.
Graph
Source: Hayeur, 2001Footnote 30
Long description for Figure 15

This line graph presents changes in zooplankton biomass (mg/m3) one year before and six years after reservoir creation.  Total biomass increased in year four, driven by increases in cladocerans and calanoids.  Cyclopoids, nauplii, and rotifers remained at relatively constant levels across years.

 

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FishFootnote 37

Monitoring of fish communities was carried out over a period of more than 20 years, from 1977, two years before the creation of the first reservoir, to 2000, and included monitoring of unaltered lakes as control sites. The general pattern of change was an increase in total fishing yields followed by a gradual return, after about a dozen years, to values comparable to pre-construction. Total fishing yield dropped quickly after impoundment, followed by a rapid increase as the added nutrients during the period of decomposition of flooded plant material influenced food webs (Figure 16).

Some shifts occurred in species composition. Lake whitefish (Coregonus clupeaformis), the dominant species in all reservoirs, increased in abundance. Northern pike (Esox lucius) also thrived and increased in abundance in some reservoirs. Recruitment was poor in lake trout (Salvelinus namaycush), likely because of winter drawdown (low water levels). In the Robert-Bourassa reservoir, 17 years after impoundment, there were relatively fewer suckers (Catostomus commersonii) and walleye and more pike, whitefish, and burbot (Lota lota) (Figure 17).

Figure 16. Relative abundance of fish caught in Robert-Bourassa reservoir, 1977-1996.
Graph
Source: Therrien et al., 2004Footnote 37
Long description for Figure 16

This stacked percentage bar graph shows relative changes in the types of fish caught in surveys in Robert-Bourassa reservoir from 1977-1996.  Following impoundment, there were shifts in the relative abundance of all species.  The most notable changes include lower relative abundance of white sucker and longnose sucker by 1996: at impoundment in 1979 these two species accounted for 40% of the catch, but accounted for less than 10% by 1996.  Lake whitefish, northern pike and burbot increased in relative abundance after 1983.  The relative abundance of cisco increased immediately after impoundment and then delined. Walleye and the generic category of other fish had a lower relative abundance after impoundment.

 

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Figure 17. Fishing yields in Robert-Bourassa reservoir, 1977-1995.
Fishing yield data from Lake Detcheverry, a natural lake, are shown for comparison.
Graph
Source: Therrien et al., 2004Footnote 37
Long description for Figure 17

This line graph presents the total yield by weight (kg/net per day) of fish caught in the Robert-Bourassa reservoir and Lake Detcheverry, a natural lake, between 1977 and 1995.  Total yield remained relatively constant in Lake Detcheverry during this time period.  In contrast, total yield showed substantial changes in Robert Bourassa: there was a sharp decrease the year of impoundment, a generally steady increase until 1988 followed by a decrease to pre-impoundment levels by 1992.

 

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Invasive non-native specie

Key finding 10
Theme: Human/ecosystem interactions

National key finding
Invasive non-native species are a significant stressor on ecosystem functions, processes, and structure in terrestrial, freshwater, and marine environments. This impact is increasing as numbers of invasive non-native species continue to rise and their distributions continue to expand.

Invasive species are still rare in the Taiga Shield. Lack of roads limits access for many species, and the severe environment may limit the survival of some species. Those species associated with human settlements, such as European house sparrows (Passer domesticus), are uncommon, but exist in the western Taiga Shield (in Yellowknife, NWT). Invasive non-native plants are mostly associated with roads and other anthropogenic disturbances. A 2006 roadside survey in the western Taiga ShieldFootnote 65 found 39 species of non-native vascular plants, including species with known invasive potential in Canada.Footnote 66

The Taiga Shield's aquatic ecology may be especially vulnerable to invasive species since it has relatively few species. The distribution of fish species such as smallmouth bass (Micropterus dolomieu), a predatory species that is known to alter species assemblages, is shifting northwards in eastern North America due to warming temperatures.Footnote 67 Arctic char (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss) were introduced near Yellowknife, NWT, as recently as 1990 to enhance recreational fishing,Footnote 68 but these species have not spread.Footnote 69

A few exotic forest pests have been introduced to the western Taiga Shield.Footnote 70 These include the larch sawfly (Pristiphora erichsonii), birch leaf edgeminer (Scolioneura betuleti), and the amber-marked birch leafminer (Profenusa thomsoni). Larch sawfly has been attacking tamarack stands since the late 1960s. Both birch leaf miner species were recently (1994-2003) found in the western Taiga Shield and commonly exist near communities. The amber-marked birch leafminer is now abundant in Yellowknife, extending into the surrounding wild birch stands, mostly along roads.

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Contaminants

Key finding 11
Theme: Human/ecosystem interactions

National key finding
Concentrations of legacy contaminants in terrestrial, freshwater, and marine systems have generally declined over the past 10 to 40 years. Concentrations of many emerging contaminants are increasing in wildlife; mercury is increasing in some wildlife in some areas.

Most contaminants in this ecozone+ are legacy contaminants, transported from long distances away and deposited on snow and vegetation. From there, they make their way into the food chain. Some heavy metals that are considered contaminants if they reach high levels, such as cadmium, are contained in the regional geology. Mercury has three sources in the Taiga Shield Ecozone+: 1) like cadmium, it is found naturally in the environment; 2) it is a component of industrial emissions around the world and is transported to the region through the atmosphere; 3) mercury in the environment becomes more biologically available in freshwater ecosystems through the flooding of land to create reservoirs.

Caribou

The Northern Contaminants Program has monitored persistent organic pollutants (POPs) and heavy metals for the last two decades, including in several caribou herds that range into the Taiga Shield ecozone+.Footnote 71

POPs such as dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyls (PCBs), dioxins, and furans, were found at very low levels in barren ground caribou and are not of concern for the health of either caribou or humans who eat caribou. Compared to other herds, cadmium levels are relatively high in the kidneys and livers of Beverly caribou, which range into the Taiga Shield in fall and winter. The probable source is cadmium from the underlying rocks, which accumulates in lichen and is then eaten by caribou. Mercury levels are changing over time in some herds across the country, but results are as yet inconclusive. Monitoring will continue through the Northern Contaminants Program on selected herds to track mercury trends from industrial sources and the degree to which mercury becomes incorporated into terrestrial food chains.

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Fish

Contaminants move into the aquatic system as well and become concentrated in higher-level predators such as some species of fish. Mercury is increasing significantly for burbot and lake trout caught in the West Basin and burbot caught in the East Arm of Great Slave Lake, while the trend is not significant for East Arm lake trout (Figure 18). Comparison of these results with analysis of mercury in fish from smaller lakes in the Taiga Plains Ecozone+ indicates that the rates of mercury increase are more pronounced in small, shallow lakes than in Great Slave Lake.Footnote 72 There is no clear relationship between increases in mercury in fish in the Great Slave Lake area and climate metrics such as mean air temperature and precipitation. The most recent increases in mercury may be related to increasing global industrial mercury emissions. In Asia, for example, mercury-emitting industrial activities such as coal-fired power plants and steel production are increasing, a trend that is likely to continue in coming decades.Footnote 73

Figure 18: Trends in mercury, PCBs, and HCH for Great Slave Lake, 1993-2008.
The East Arm of Great Slave Lake is in the Taiga Shield ecozone+. Samples were collected in the Lutsel K'e area. The West Basin of the lake is in the Taiga Plains ecozone+. Samples were collected in the Hay River area (lake trout) and Slave River outflow (burbot). Lines show significant trends (p less than 0.05). PCBs show no significant trends.
three scatter plots
Source: Evans, 2009Footnote 72
Long description for Figure 18

These three scatter plots combined with linear graphs show the following information:

Mercury (ug/g)
YearHay River trout (West Basin trout)Lutsel K'e trout (East Arm trout)Hay River burbot (West Basin burbot)Lutsel K'e burbot (East Arm burbot)
1993----
1994----
1995-0.12--
1996--0.08-
1997----
1998----
19990.110.140.110.08
2000-0.260.130.12
20010.200.150.180.12
20020.160.130.160.12
2003----
20040.170.150.180.17
20050.180.190.11-
20060.210.160.16-
20070.210.190.24-
20080.270.190.250.19
Average PCBs (ng/g)
YearHay River trout (West Basin trout)Lutsel K'e trout (East Arm trout)Hay River burbot (West Basin burbot)Lutsel K'e burbot (East Arm burbot)
1993142575138
1994----
1995-21--
1996--96-
1997----
1998----
1999281411880
2000-17168127
20011126180126
20023783112
2003----
20041729101174
2005155072-
2006171864-
2007726--
2008----
Average HCH (ng/g)
YearHay River trout (West Basin trout)Lutsel K'e trout (East Arm trout)Hay River burbot (West Basin burbot)Lutsel K'e burbot (East Arm burbot)
199323711
1994----
1995-1--
1996--7-
1997----
1998----
19993153
2000-168
20012267
20020136
2003----
20041113
2005003-
2006002-
200700--
2008----

 

Legacy POPs are unchanged or declining in Great Slave Lake fish. PCB and DDT trends were unchanged from 1992-2007, while hexachlorocyclohexane (HCH) decreased significantly in three of the four sample groups (Figure 18). Changes in lake ecology and fish trophic structure in Great Slave Lake may either be accentuating or masking trends in contaminants. For example, organic contaminants accumulate more in fatty tissues and the lake trout fat levels have decreased in recent years, which may be related to changes in the relative numbers of different species in the lake or to other changes in lake ecology.Footnote 72

A study of Mackenzie River burbotFootnote 74 concluded that increasing trends in mercury and PCBs may be related to increased productivity in the aquatic environment due to climate change. Contaminants may move more readily into the food web under conditions of higher productivity. The picture may be further complicated by changes in forest fire regime. Kelly et al., 2006Footnote 75 in a study in the Jasper, Alberta area, demonstrated that fish from lakes with recent forest fires in their catchment areas had elevated levels of mercury. This was attributed both to increases in mercury input to the lakes and to increases of nutrients that enhanced productivity and altered food webs.

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Mercury in fish affected by reservoirs

When new reservoirs are created, the flooded vegetation decomposes, increasing the mercury load, creating low-oxygen conditions and increasing the carbon source for bacteria that convert inorganic mercury to methylmercury – which is then taken up by aquatic organisms, including plankton, insects, and fish. Creation of a reservoir typically leads to a rapid increase in mercury in the food chain, followed by a slower reduction in methylmercury as the store of flooded, rotting vegetation is depleted.Footnote 76

In the James Bay region in the eastern Taiga Shield, the La Grande hydroelectric development affected mercury levels in the associated rivers and wetlands. Mercury levels in fish at the La Grande complex have been monitored since the late 1970s.Footnote 77 All La Grande reservoirs show the same pattern of increase and subsequent decrease in fish mercury levels (Figure 19). Concentrations of mercury in fish usually peak between 5 to 13 years after flooding. Peak levels range from to three- to eight-fold increases compared to background levels. Mercury concentrations then gradually decline, 10 to 35 years after flooding, to the range of concentrations measured in natural lakes of the area. The broad time ranges reflect different species, different trophic levels (Table 3), and differing reservoir characteristics. Northern pike, as top predators, acquire the highest levels of mercury and take longest to return to background levels.

Figure 19: Mercury in northern pike in reservoirs of the La Grande complex, 0 to 29 years following impoundment.
Size class is 700 mm length. Note that the mercury limit for themarket of fish is 0.5 mg/kg. Dates of flooding (beginning of filling period): Robert-Bourassa-1978, La Grande 3-1981, La Grande 1-1993, Caiapiscau-1981, and Laforge 2-1983.
Graph
Graph
Source: updated from Schetagne et al., 2003Footnote 77 based on data provided by Hydro-Québec
Long description for Figure 19

These two line graphs show total mercury levels in northern pike in five reservoirs in the La Grande complex. Mercury levels in Robert-Bourassa, La Grande 3 and La Grande 1 reservoirs (top graph) spike between 10 and 15 years, at triple or quadruple the range of mean levels measured under natural conditions for that size class of fish (700 mm). The mercury limit for the market of fish is 0.5 mg/kg. Mercury levels in the pike in the Caniapiscau and Laforge 2 reservoirs (bottom graph) peaked slightly earlier (10-12 years after impoundment) and at lower levels than the other reservoirs. After the spike, the levels decline steadily; after 25 years, mercury levels in the La Grande 1, Caniapiscau and Laforge 2 were nearing pre-impoundment levels, and Robert-Bourassa and La Grande 3 exhibit downward trends.

 

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Table 3: Rise and fall of mercury levels in fish of different trophic levels, La Grande complex
Increasing trophic levelSpeciesPeak mercury levelsTiming of peakReturn to background
Non-fish-eating (longnose sucker and lake whitefish)0.3-0.7 mg/kg (3 to 6 times background levels)5 to 10 years after flooding10 to 20 years after flooding
Fish-eating (walleye and lake trout)2.4-3.1 mg/kg (4 to 6 times background levels)10 years after flooding20 to 30 years after flooding
Northern pike (fish-eating and, in some reservoirs, consuming other fish-eating fish)1.9-4.7 mg/kg (3 to 8 times background levels)10 to 13 years after flooding20 years to (projected) 35 years after flooding

Source: Therrien and Schetagne, 2008, 2009Footnote 78 Footnote 79 Footnote 80

The increases in mercury from impoundment and flooding of land affected streams and lakes downstream of the reservoirs. Mercury was transported downstream mainly dissolved in the water and in suspended particulate matter, but also in plankton.Footnote 81 Mercury from flooded soils was taken up by plankton in the reservoirs, a process that was enhanced by the high levels of carbon and nutrients released from decomposing flooded plants.Footnote 82 The main route of mercury transfer into downstream fish was through zooplankton drifting down from the impounded waters.Footnote 81 Lake whitefish caught in Cambrien Lake, 275 km downstream from the Caniapiscau reservoir, had elevated mercury levels but there was no effect on fish caught 355 km below the reservoir.Footnote 81 Mercury returned to pre-development levels in Cambrien Lake whitefish 10 years after impoundment.

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Nutrient loading and algal blooms

Key finding 12
Theme: Human/ecosystem interactions

National key finding
Inputs of nutrients to both freshwater and marine systems, particularly in urban and agriculture-dominated landscapes, have led to algal blooms that may be a nuisance and/or may be harmful. Nutrient inputs have been increasing in some places and decreasing in others.

The main anthropogenic source of nutrient addition to freshwater systems in the Taiga Shield ecozone+ has been hydroelectric development, through flooding and reservoir creation. This is discussed under Dams and reservoirs on page 23.

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Climate change

Key finding 14
Theme: Human/ecosystem interactions

National key finding
Rising temperatures across Canada, along with changes in other climatic variables over the past 50 years, have had both direct and indirect impacts on biodiversity in terrestrial, freshwater, and marine systems.

Coverage and distribution of climate trend data are poor for this ecozone+. Temperatures increased whereas precipitation was variable; snow cover duration decreased at the three stations with measurements.7 Most obvious ecological impacts are from changes in permafrost in the south and east of the ecozone+, and changes in hydrology. There are indications of other impacts, for example caribou may be affected by the increase in ice content in snow (see box on page 41).

Climate change will have wide-ranging impacts on the Taiga Shield, because climate is a strong driver of the region's ecological structure and processes. However, with little current monitoring within the ecozone+, most impact projections for the Taiga Shield are based on data collected elsewhere. The land cover is mainly boreal forest and forest tundra. Boreal forest ecosystems and fire regimes are projected to change as trends in climate alter vegetation or fuels, lightning, and fire severity. Climate change will likely reduce the area of boreal forest and increase fragmentation.Footnote 83 Warmer temperatures could also introduce new pests and wildlife diseases.

Climate trends

Increasing temperatures and shorter duration of snow cover are the most pronounced trends observed at climate stations in the Taiga Shield Ecozone+ (Table 4).

Table 4: Overview of climate trends for Canada and for the Taiga Shield ecozone+, 1950-2007
Climate variableTrends since 1950Representativeness of trends
TemperatureCanada: annual mean temperatures have increased more (>2oC) in northern and northwestern Canada and less (<1oC) in eastern Canada. Taiga Shield: annual mean temperatures generally increased; Yellowknife and Kuujjuarapik (on the coast of Hudson Bay) showed significant increases of >1.5oC. Seasonal trends are shown in Figure 20.The Taiga Shield ecozone+ includes two distinct climate regions either side of Hudson Bay with a poor distribution of stations for computing an ecozone+ average. There are few stations in the western Taiga Shield and those east of Hudson Bay are mainly coastal. Trends are thus described for specific locations.
PrecipitationCanada: total annual precipitation has generally increased, though there are few individual stations with significant trends. Taiga Shield: total annual precipitation changed little at most stations – Fort Reliance being the exception, with a significant increase. Seasonal trends were quite variable – predominantly increasing, but included significant decreases at some seasons at two stations in Labrador (Figure 21).The Taiga Shield ecozone+ includes two distinct climate regions either side of Hudson Bay with a poor distribution of stations for computing an ecozone+ average. There are few stations in the western Taiga Shield and those east of Hudson Bay are mainly coastal. Trends are thus described for specific locations.
Snow

Canada: the duration of snow cover showed the most pronounced decreases in the spring, especially in western and northern stations. Taiga Shield: significant decreases in snow cover duration (1950-2006) occurred in the spring (February-June), at the three stations with sufficient data for analysis:

  • Yellowknife (11 days)
  • Kuujjuarapik (13 days)
  • Kuujjuaq (36 days)
The Taiga Shield ecozone+ includes two distinct climate regions either side of Hudson Bay with a poor distribution of stations for computing an ecozone+ average. There are few stations in the western Taiga Shield and those east of Hudson Bay are mainly coastal. Trends are thus described for specific locations.

Source: Zhang et al., 2011Footnote 7 and data provided by the authors

Table Summary

This table presents highlights of an analysis of Canadian climate records, checked and corrected for sources of systematic error and excluding stations with strong urban warming effects.

 

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Figure 20: Trends in temperature by season, 1950-2007.
Total change in temperature over the 58-year time period is indicated for sites for which the trend is statistically significant. Season definitions – spring: March-May; summer: June-August; fall: September-November; winter: December-February.
Map
Source: Zhang et al., 2011Footnote 7
Long description for Figure 20

This set of four maps depicts change in mean annual temperature in spring, summer, fall, and winter (oC) in cities and towns in the Taiga Shield Ecozone+ between 1950 and 2007. Various locations have shown significant increases in mean annual temperature, with winter temperatures in Yellowknife, NT and Uranium City, SK increasing by 4.8o and 4.7o respectively. Kuujjuarapik, QC experienced an increase of 2.5o in the summer and 1.6o in the fall, and fall temperature in Kuujjuaq, QC increased by 1.7o.

 

Figure 21: Change in the amount of precipitation, 1950-2007 by season.
Change is expressed as a percentage of the 1961-1990 mean. Season definitions – spring: March-May; summer: June-August; fall: September-November; winter: December-February.
Map
Source: Zhang et al., 2011Footnote 7
Long description for Figure 21

In this set of four maps, change is expressed as a percentage of the 1961-1990 mean for spring, summer, fall, and winter. Several cities experienced a significant increase in precipitation (>40%) in one of the four seasons, including Fort Reliance, NT (spring, fall and winter), Uranium City, SK (spring), Brochet, MB (winter) and Nitchequon, QC (spring and winter). A couple cities experienced more moderate increases (10-40%) in the summer (Nain, NF and Kuujjuaq, QC) and fall (Kuujjuaq and Kuujjuarapik, QC). Churchill Falls, NF (winter) and Hopedale, NF and the Yellowknife Hydro station (summer) were the only places to experience significant decreases in precipitation.

 

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Aboriginal knowledge of climate trends

Aboriginal people recognize the trends in increasing temperatures and note that temperatures are more variable and less predictable than in the past.Footnote 84 Regional differences are also apparent and highlight how much climate trends vary at local scales. Some specific observations of climate-related change related to winds in the Taiga Shield:

  • Winds are stronger and change direction more frequently (Lutsel K'eFootnote 54).
  • The strongest winds are coming later in the fall (NunutsiavutFootnote 85).
  • From the mid-1980s to the mid 1990s, April and May winds blew mostly from the north, reducing the size of Canada goose flocks, slowing spring melt, and contributing to spring and summer cooling trends in eastern Hudson Bay.Footnote 86

Aboriginal knowledge describes a decline in rainfall in some regions (Northern Saskatchewan, 2006,Footnote 87 Nunutsiavut, 2007,Footnote 85 James Bay, 2008Footnote 88).

A suite of similar changes in snowfall has been reported for several regions of the eastern Taiga Shield. Snow arrives later in the season and typically there is less of it. Heavy snowfalls are rare, and the snow melts more rapidly, leading to less accumulation, possibly because of increased winds (Nunutsiavut, 2007,Footnote 85 Hudson and James Bay regions, 2007-2008Footnote 88 Footnote 89).

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Climate trends and caribou habitat: Bathurst caribou winter range

The Bathurst Caribou Herd's winter range is in the western Taiga Shield. The 2009 calving ground census for the herd indicates a severe recent population decline (Figure 27 ), the causes of which are not known. A study of ecological change related to the herd's winter and pre-calving migration conditions found changes in two important climate-related habitat indicators.

  1. Caribou tend to move quickly through or avoid areas of recent burns which have low lichen abundance.Footnote 90 Footnote 91 The extent of mature (older than 50 years) forest declined significantly on the winter range since 1959, due to increased fire, which was in turn positively correlated with summer (June-September) temperature increases. Analysis is based on data from the large fire database presented under Fire trends on page 59, combined with analysis of satellite imagery and of climate records.
  2. Caribou dig holes in the snow to access lichens in the winter and adverse snow conditions result in them using up more energy – resulting in changes to body condition, calf survival the following spring, or, in extreme cases, resulting in starvation.Footnote 92, Footnote 93 Accessibility of lichens in winter for the Bathurst caribou may have deteriorated because the snow has become harder. Ice content in snow, estimated from climate and snow data, increased significantly from 1963-2006. The ice was mainly (90%) from freeze-thaw cycles in spring, with rain-on-snow events accounting for, on average, 10% of the ice content. Researchers have suggested a threshold value for major impacts on caribou of approximately 10 mm water equivalent of ice content in snow.Footnote 94 Figure 22 shows the increasing trend in the percent of years in which snow hardness exceeded this threshold. The observation of increasingly "hard" snow or icy crust in the snowpack corresponds with Aboriginal Traditional Knowledge on the subject, as well as with projections of global climate change models.

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Figure 22: Trend in years with high ice content in snow, Bathurst Caribou Herd winter range, 1963-2006.
Ice content in snow (ICIS) is estimated from climate and snow depth data (based on analysis of data to detect conditions that produce layers of ice in snow). ICIS values are based on an average of four climate stations: Yellowknife, Fort Reliance, Rae Lakesand Uranium City.
Graph
Source: based on Chen et al., In prep.Footnote 95
Long description for Figure 22

This bar graph shows the following information:

YearPercent of years with Ice in Snow index > 10 mm water equivalent
1963-6914
1970s20
1980s20
1990s30
2000-0643

This figure also has a photograph of Bathurst caribou in late winter in the western Taiga Shield.

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Ecosystem services

Key finding 15
Theme: Human/ecosystem interactions

National key finding
Canada is well endowed with a natural environment that provides ecosystem services upon which our quality of life depends. In some areas where stressors have impaired ecosystem function, the cost of maintaining ecosystem services is high and deterioration in quantity, quality, and access to ecosystem services is evident.

Historically, the ecosystem services of the Taiga Shield Ecozone+ supported Aboriginal people, and traditional/country foods and resources remain important, especially in medium and small size communities (Figure 23). Many non-Aboriginal residents also make extensive use of country foods. There are regional and cultural variations. For example, geese account for as much as a quarter of wild meat consumption for the James Bay Cree,Footnote 57 Footnote 96 Footnote 97 while barren ground caribou are important traditional food for the Dene and Innu.Footnote 54 Footnote 84 Footnote 98 Footnote 99 Fish are also an important traditional food throughout the ecozone+. Other traditional and contemporary uses of plants and animals include medicinesFootnote 100 and crafts.Footnote 101

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Figure 23: Proportion of households consuming traditional/country foods, 1999 and 2004, NWT communities in the Taiga Shield ecozone+.
Percent of households reporting thatmore than 75% of their meat and fish was harvested from the NWT. Communities surveyed: Behchokò (Rae-Edzo), Detah, Gamètì (Rae Lakes), Lutselk'e, Wekweètì, Yellowknife.
Graph
Source: data from NWT Bureau of Statistics and 2004 NWT Regional Employment and Harvesting Survey, reported in Northwest Territories Environment and Natural Resources, 2009Footnote 69
Long description for Figure 23

This bar graph shows the following information:

Percentage of households
YearCommunity size - Large (Yellowknife)Community size - MediumCommunity size - Small
19998%56%63%
20045%38%53%

 

Changes in availability of traditional/country foods

Maintaining strong populations of targeted species is not enough to ensure ongoing supply and access to traditional/country foods. Socio-economic factors are important, as are a range of ecosystem characteristics. The examples below illustrate some categories of threats to the ongoing provision of ecosystem goods and services in the Taiga Shield Ecozone+.

Animal population declines

In the western Taiga Shield, barren ground caribou herds have been in decline since the mid-1990s and the Bathurst Herd in particular (which winters in the western Taiga Shield) has declined severely in the past few years (see Migratory tundra caribou on page 47). This has resulted in the implementation of emergency management measures that directly affect hunting in the ecozone+.

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Environmental change affecting access to hunting and fishing areas

Trail networks linking communities and harvesting areas in regions with no roads provide access to hunting and fishing areas. Climate change in northern Quebec has affected timing and security of access to local environments and to key food resources along these traditional trail networks.Footnote 102

Deterioration in quality or safety of foods

Contaminants from long-range atmospheric transport (see Contaminants on page 30) present ongoing concerns about food safety across the ecozone+. In the James Bay region, Aboriginal communities were affected by the increases in mercury from the reservoirs of the La Grande complex (see Mercury in fish affected by reservoirs on page 33). Mercury in the Cree population increased to levels of concern, then declined as the levels in fish went down and as people changed their traditional fishing patterns and reduced their consumption of fish.Footnote 103 Contaminant-related health advisories have impacts on local economies, nutrition and on social and mental well-being. The threat of harm from a traditional food sources leads to pervasive and persistent anxiety and social effects.Footnote 104

Changes in wildlife

Although the populations of Canada geese have increased since the mid-1990s in the eastern Taiga Shield,Footnote 105 hunting success has declined among the James Bay Cree.Footnote 106 Hunters sayFootnote 106 Footnote 107 that a number of behavioural changes in both geese and hunters are causing this problem – for example: goose migratory patterns have changed; geese fly higher and the migration period is shorter; geese have changed their migration route, going further inland than they used to. Hunters relate these observations to a range of causes, such as changes in weather patterns, reduction of eelgrass, impacts from hydroelectric development, and changes in hunting practices. Some changes in hunting practices are in turn linked to environmental change. Traditional hunting relies on rotating use of many hunting sites to minimize disturbance to the migrating geese, but in some places environmental change has led to fewer hunting sites being used (Figure 24), reducing the success of the hunt.

Figure 24: Map of hunting sites used for the spring goose hunt, Blackstone Bay, Wemindji territory, 1979 and 2006.
The reduction in number of sites used and their clustering around a central point, was due to two causes: 1) environmental changes in some sites made them no longer suitable as goose habitat; 2) some sites could not be reached because ice on the bay has become thinner and unsafe in the spring. The triangle indicates the location of the camp.
Map
Source: Scott, 1983 in Peloquin, 2007Footnote 107
Long description for Figure 24

This bar graph shows the following information:

Percentage of households
YearCommunity size - Large (Yellowknife)Community size - MediumCommunity size - Small
19998%56%63%
20045%38%53%

 

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What is the value of a caribou herd?

A holistic approach to valuation of ecosystem goods and services

A study conducted for the Beverly and Qamanirjuaq Caribou Management Board in 2008Footnote 108 examined the value of provisioning and cultural goods and services provided by the Beverly and Qamanirjuaq Herds. The study was built on a model that considered the value of these services to include:

  • direct-use values: primarily meat, but also hides and antlers as input to arts, crafts and cultural products;
  • indirect values:
    • values of experiences and other intangible benefits: for example, recreational enjoyment, kinship and bonding, education in traditional ways of life;
    • values of the existence of the caribou: as a bequest to future generations and for options to hunt at a later time.

Only the direct-use values can be quantified in terms of market value (Table 5). The Beverly Herd's estimated direct-use value was $4.8 million in 2005/06, primarily ($4.1 million) as domestic harvest, with 76% of the harvest that year being by Aboriginal communities in northern Saskatchewan.

Table 5: Estimates of the annual direct-use value of the Beverly and Qamanirjuaq Caribou Herds

Estimates of the annual direct-use value of the Beverly and Qamanirjuaq Caribou Herds(total $19.9 million/year)

Table 5.1 by jurisdiction
Jurisdiction$ million/yearPercent
Nunavut11.859
Manitoba3.820
Saskatchewan3.417
NWT0.84
Table 5.2 by harvest
Harvest$ million/yearPercent
Domestic (Aboriginal)14.774
Outfitter4.121
Commercial and licensed1.05
Table 5.3 by herd
Herd$ million/yearPercent
Qamanirjuaq1576
Beverly4.824

Calculated for domestic and resident (licensed), outfitting and commercial harvests, based on value of replacing meat and hides (taking into account the costs of hunting and regional differences in costs such as transport). Outfitting was treated as an economic activity and its annual net contribution to the GDP was calculated. Estimates are based on 2005/06 statistics.
Source: data from InterGroup Consultants Ltd, 2008Footnote 108

Indirect values were examined based on previous studies in the region augmented with questionnaires and interviews. The authors concluded that hunting caribou and associated activities (such as preparation of and sharing of meat, and community feasts) were viewed by the people throughout the ranges of the two herds as integral to the maintenance and transfer of knowledge, skills, and cultural norms. Many people interviewed talked about how important hunting caribou was to their identity and to the revitalization of their communities.

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Small industries

Fur trapping, once a major part of the Taiga Shield's economy, is still pursued by a relatively small number of Taiga Shield residents (Figure 25). Despite the shrinking of the industry, due to changes in social values and consumption patterns, it remains an important source of income in many small communities.

Figure 25: Active trappers in the Northwest Territories portion of the Taiga Shield, 2001-2008.
Graph
Source: data from the NWT Fur Harvest Database,2008, reported in Northwest Territories Environment and Natural Resources, 2009Footnote 69
Long description for Figure 25

This line graph shows the following information:

YearNumber of trappers
2001165
2002140
2003166
2004180
2005157
2006145
2007151
2008117

 

 

Small-scale wood harvesting is another modest consumer of Taiga Shield ecosystem services. Most wood is harvested for firewood or by small-scale local businesses selling lumber and fuel. While the level of harvest is too low to have a serious impact on the Taiga Shield's boreal forest, it is an important contributor to the cash and non-cash economy of many small communities.Footnote 69

Footnotes

Footnote 3

Federal, Provincial and Territorial Governments of Canada. 2010. Canadian biodiversity: ecosystem status and trends 2010. Canadian Councils of Resource Ministers. Ottawa, ON. vi + 142 p.

Return to footnote 3

Footnote 7

Zhang, X., Brown, R., Vincent, L., Skinner, W., Feng, Y. and Mekis, E. 2011. Canadian climate trends, 1950-2007. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 5. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 21 p.

Return to footnote 7

Footnote 17

Monk, W.A. and Baird, D.J. 2011. Biodiversity in Canadian lakes and rivers. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 19. Canadian Councils of Resource Ministers. Ottawa, ON. Draft report.

Return to footnote 17

Footnote 30

Hayeur, G. 2001. Summary of knowledge acquired in northern environments from 1970 to 2000. Hydro-Québec. Montréal, QC. x + 110 p. .

Return to footnote 30

Footnote 37

Therrien, J., Verdon, R. and Lalumière, R. 2004. Environmental monitoring at the La Grande complex. Changes in fish communities. Summary report 1977-2000. GENIVAR Groupe Conseil Inc. and Direction Barrages et Environnement, Hydro-Québec Production. 129 p. + appendices.

Return to footnote 37

Footnote 51

IUCN. 1994. Guidelines for protected area management categories. Commission on National Parks and Protected Areas with the assistance of the World Conservation Monitoring Centre, International Union for Conservation of Nature. Gland, Switzerland and Cambridge, UK. x + 261 p.

Return to footnote 51

Footnote 52

Environment Canada. 2009. Unpublished analysis of data by ecozone+ from: Conservation Areas Reporting and Tracking System (CARTS), v.2009.05 [online]. Canadian Council on Ecological Areas. (accessed 5 November, 2009).

Return to footnote 52

Footnote 53

CCEA. 2009. Conservation Areas Reporting and Tracking System (CARTS), v.2009.05 [online]. Canadian Council on Ecological Areas. (accessed 5 November, 2009).

Return to footnote 53

Footnote 54

Lutsel K'e Dene First Nation, Parlee, B., Basil, M. and Casaway, N. 2001. Final report: Traditional Ecological Knowledge in the Kaché Tué study region. Lutsel K'e Dene First Nation. 87 p.

Return to footnote 54

Footnote 55

Berkes, F. and Turner, N. 2005. Knowledge, learning and the resilience of social-ecological systems. In Managing the commons: conservation of biodiversity. Edited by Merino, L. and Robson, J. Instituto Nacional de Ecologia. Mexico City, Mexico. pp. 21-31.

Return to footnote 55

Footnote 56

Parlee, B., Manseau, M. and Lutsel K'e Dene First Nation. 2005. Using traditional knowledge to adapt to ecological change: Denesoline monitoring of caribou movements. Arctic 58:26-37.

Return to footnote 56

Footnote 57

 Bussières, V. 2005. Towards a culturally-appropriate locally-managed protected area for the James Bay Cree community of Wemindji, northern Québec. Thesis (Master of Public Policy and Public Administration). Concordia University, Department of Geography, Planning and Environment. Montréal, QC. 125 p.

Return to footnote 57

Footnote 58

Byers, T. 1999. Perspectives of Aboriginal peoples on wildlife research. Wildlife Society Bulletin 27:671-675.

Return to footnote 58

Footnote 59

Van Kessel, J.C. 2002. Taking care of bison: community perceptions of the Hook Lake Bison Recovery Project in Fort Resolution, NT, Canada. Thesis (M.Sc.). University of Alberta, Department of Renewable Resources. Edmonton, AB. 155 p.

Return to footnote 59

Footnote 60

Spak, S. 2005. The position of indigenous knowledge in Canadian co-management organizations. Anthropologica 47:233-246.

Return to footnote 60

Footnote 61

Kendrick, A., Lyver, P.O.B. and Lutsel K'e Dene First Nation. 2005. Denesoline (Chipewyan) knowledge of barren-ground caribou (Rangifer tarandus groenlandicus) movements. Arctic 58:175-191.

Return to footnote 61

Footnote 62

Leckie, D., Burt, W., Johnson, L., Hardman, D., Hill, D., Paradine, D. and Tammadge, D. 2006. Deforestation mapping activity summaries for Canada's national deforestation estimate 2006. Canadian Forest Service. Victoria, BC. 25 p.

Return to footnote 62

Footnote 63

Hydro-Québec. 2004. Eastmain-1-A powerhouse and Rupert diversion. Environmental impact statement executive summary. Hydro-Québec Production. ii + 17 p.

Return to footnote 63

Footnote 64

Weissenberger, S., Lucotte, M., Houel, S., Soumis, N., Duchemin, E. and Canuel, R. 2010. Modeling the carbon dynamics of the La Grande hydroelectric complex in northern Quebec. Ecological Modelling 221:610-620.

Return to footnote 64

Footnote 65

Oldham, M.J. 2007. 2006 Survey of exotic plants along Northwest Territories highways. Environment and Natural Resources, Government of the Northwest Territories. 44 p.

Return to footnote 65

Footnote 66

Canadian Botanical Conservation Network. 2008. Invasive plant lists [online]. Royal Botanical Gardens. http://archive.rbg.ca/cbcn/en/projects/invasives/i_list.html Archived website.

Return to footnote 66

Footnote 67

Jackson, D.A. and Mandrak, N.E. 2002. Changing fish biodiversity: predicting the loss of cyprinid biodiversity due to global climate change. In Fisheries in a changing climate. Edited by McGinn, N.A. American Fisheries Society Symposium 32. American Fisheries Society. Bethesda, MD. pp. 89-98.

Return to footnote 67

Footnote 68

Crossman, E.J. 1991. Introduced freshwater fishes: a review of the North American perspective with emphasis on Canada. Canadian Journal of Fisheries and Aquatic Sciences 48:46-57.

Return to footnote 68

Footnote 69

Environment and Natural Resources Government of the Northwest Territories.. 2009. Northwest Territories State of the Environment Report [online]. (accessed 6 October, 2011).

Return to footnote 69

Footnote 70

Digweed, S.C. and Langor, D.W. 2004. Distributions of leafmining sawflies (Hymenoptera: Tenthredinidae) on birch and alder in northwestern Canada. Canadian Entomologist 136:727-731.

Return to footnote 70

Footnote 71

Gamberg, M. 2009. Arctic caribou and moose contaminant monitoring program. In Synopsis of research conducted under the 2008-2009 Northern Contaminants Program. Edited by Smith, S., Stow, J. and Edwards, J. Indian and Northern Affairs Canada. Ottawa, ON. pp. 179-184.

Return to footnote 71

Footnote 72

Evans, M.S. 2009. Spatial and long-term trends in the persistent organic contaminants and metal in the lake trout and burbot from the Northwest Territories. In Synopsis of research conducted under the 2008-2009 Northern Contaminants Program. Edited by Smith, S., Stow, J. and Edwards, J. Indian and Northern Affairs Canada. Ottawa, ON. pp. 152-163.

Return to footnote 72

Footnote 73

Wong, C.S.C., Duzgoren-Aydin, N.S., Aydin, A. and Wong, M.H. 2006. Sources and trends of environmental mercury emissions in Asia. Science of the Total Environment 368:649-662.

Return to footnote 73

Footnote 74

Carrie, J., Wang, F., Sanei, H., Macdonald, R.W., Outridge, P.M. and Stern, G.A. 2010. Increasing contaminant burdens in an arctic fish, burbot (Lota lota), in a warming climate. Environmental Science & Technology 44:316-322.

Return to footnote 74

Footnote 75

Kelly, E.N., Schindler, D.W., St Louis, V.L., Donald, D.B. and Vlaclicka, K.E. 2006. Forest fire increases mercury accumulation by fishes via food web restructuring and increased mercury inputs. Proceedings of the National Academy of Sciences of the United States of America 103:19380-19385.

Return to footnote 75

Footnote 76

Schetagne, R., Plante, M. and Babo, S. 2006. Fact sheet 1: mercury in hydroelectric reservoirs. In Issue of mercury for Hydro-Québec. Hydro-Québec. pp. 1-5.

Return to footnote 76

Footnote 77

Schetagne, R., Therrien, J. and Lalumière, R. 2003. Environmental monitoring at the La Grande complex. Evolution of fish mercury levels. Summary report 1978-2000. Direction Barrages et Environnement, Hydro-Québec Production and Groupe conseil GENIVAR inc. 185 p. + appendix.

Return to footnote 77

Footnote 78

Therrien, J. and Schetagne, R. 2008. Réseau de suivi environnemental du complexe La Grande (2007). Évolution du mercure dans la chair des poissons dans le secteur est. Joint report by Hydro-Québec and GENIVAR Société en commandite. 55 p. + appendices.

Return to footnote 78

Footnote 79

Therrien, J. and Schetagne, R. 2008. Aménagement hydroélectrique de L'Eastmain-1. Suivi environnemental en phase d'exploitation (2007). Suivi du mercure dans la chair des poissons. Joint report by Hydro-Québec and GENIVAR Société en commandite. 45 p. + appendices.

Return to footnote 79

Footnote 80

Therrien, J. and Schetagne, R. 2009. Réseau de suivi environnemental du complexe La Grande (2008). Évolution du mercure dans la chair des poissons dans le secteur ouest. Joint report by Hydro-Québec and GENIVAR Société en commandite. 50 p. + appendices.

Return to footnote 80

Footnote 81

Schetagne, R., Doyon, J.F. and Fournier, J.J. 2000. Export of mercury downstream from reservoirs. Science of the Total Environment 260:135-145.

Return to footnote 81

Footnote 82

Tremblay, A., Lucotte, M. and Schetagne, R. 1998. Total mercury and methylmercury accumulation in zooplankton of hydroelectric reservoirs in northern Quebec (Canada). Science of the Total Environment 213:307-315.

Return to footnote 82

Footnote 83

Weber, M.G. and Flannigan, M.D. 1997. Canadian boreal forest ecosystem structure and function in a changing climate: impact on fire regimes. Environmental Reviews 5:145-166.

Return to footnote 83

Footnote 84

Lutsel K'e Dene Community Members, Krieger, M., Catholique, H., Drygeese, D., Casaway, N., Lantz, A., Desjarlais, P., Boucher, E., Michel, P., Catholique, S., Lockhart, J. and Catholique, L. 2005. Ni hat'ni - watching the land: results of 2003-2005 monitoring activities in the traditional territory of the Lutsel K'e Denesoline - final report. Lutsel K'e Dene First Nation. 109 p.

Return to footnote 84

Footnote 85

Davies, H. 2007. Inuit observations of environmental change and effects of change in Anaktalak Bay, Labrador. Thesis (Master of Environmental Studies). Queen's University, School of Environmental Studies. Kingston, ON. 156 p.

Return to footnote 85

Footnote 86

McDonald, M., Arragutainaq, L. and Novalinga, Z. (compilers). 1997. Voices from the bay: Traditional Ecological Knowledge of Inuit and Cree in the Hudson Bay bioregion. Canadian Arctic Resources Committee and Environmental Committee of the Municipality of Sanikiluaq. Ottawa, ON. xiii + 98 p.

Return to footnote 86

Footnote 87

Ermine, W., Nilson, R., Sauchyn, D., Sauve, E. and Smith, R.Y. 2005. Isi askiwan -- the state of the land: Prince Albert Grand Council Elders' Forum on Climate Change. Prairie Adaptation Research Collaborative. 40 p.

Return to footnote 87

Footnote 88

Municipality of Sanikiluaq and Nunavuummi Tasiujarjuamiuguqatigiit Katutjiqatigiingit (NTK). 2008. Community Environmental Monitoring Systems (CEMS) workshop summary report, January 17, 2008-January 21, 2008. Update of Voices from the Bay. Municipality of Sanikiluaq. Sanikiluaq, NU. 41 p.

Return to footnote 88

Footnote 89

Inuit Circumpolar Council (Canada). 2007. Table 2: regional environmental changes observed by Inuit and Cree [online]. (accessed 8 December, 2007).

Return to footnote 89

Footnote 90

Thomas, D.C. and Kiliaan, H. 1998. Fire-caribou relationships: (IV) recovery of habitat after fire on the winter range of the Beverly Herd. Technical Report Series No. 312. Canadian Wildlife Service, Prairie and Northern Region. Edmonton, AB. 115 p.

Return to footnote 90

Footnote 91

Rupp, T.S., Olson, M., Adams, L.G., Dale, B.W., Joly, K., Henkelman, J., Collins, W.B. and Starfield, A.M. 2006. Simulating the influences of various fire regimes on caribou winter habitat. Ecological Applications 16:1730-1743.

Return to footnote 91

Footnote 92

Russell, D.E., White, R.G. and Daniel, C.J. 2005. Energetics of the Porcupine Caribou Herd: a computer simulation model. Technical Report Series No. 431. Canadian Wildlife Service. Ottawa, ON. 64 p.

Return to footnote 92

Footnote 93

Griffith, B., Douglas, D.C., Walsh, N.E., Young, D.D., McCabe, T.R., Russell, D.E., White, R.G., Cameron, R.D. and Whitten, K.R. 2002. The Porcupine Caribou Herd. In Arctic refuge coastal plain terrestrial wildlife research summaries. Edited by Douglas, D.C., Reynolds, P.E. and Rhode, E.B. U.S. Geological Survey, Biological Resources Division, Biological Science Report USGS/BRD/BSR-2002-0001. pp. 8-37.

Return to footnote 93

Footnote 94

Putkonen, J., Grenfell, T.C., Rennert, K., Bitz, C., Jacobson, P. and Russell, D. 2009. Rain on snow: little understood killer in the North. EOS 90:221-222.

Return to footnote 94

Footnote 95

Chen, W., Russell, D.E., Gunn, A., Croft, B., Chen, W., Fernandes, R., Zhao, H., Li, J., Zhang, Y., Koehler, K., Olthof, I., Fraser, R.H., Leblanc, S.G., Henry, G.R., White, R.G. and Finstad, G.L. 2009. Habitat indicators for migratory tundra caribou under a changing climate: winter and pre-calving migration ranges (PDF, 292KB) [online]. Unpublished report. (accessed 7 July, 2013). Draft report available through Wek'eezhii Renewable Resources Board. (accessed 17 May, 2011).

Return to footnote 95

Footnote 96

Belinsky, D.L. 1998. Nutritional and sociocultural significance of Branta canadensis (Canada goose) for the eastern James Bay Cree of Wemindji, Quebec. Thesis (M.Sc.). McGill University, School of Dietetics and Human Nutrition. Montréal, QC. 194 p.

Return to footnote 96

Footnote 97

Belinsky, D.L. and Kuhnlein, H.V. 2000. Macronutrient, mineral, and fatty acid composition of Canada goose (Branta canadensis): an important traditional food resource of the eastern James Bay Cree of Quebec. Journal of Food Composition and Analysis 13:101-115.

Return to footnote 97

Footnote 98

Petch, V., Larcombe, L., Pettipas, L. and Tester, S. 1998. Manitoba Model Forest: archaeological and Anishinabe Pimadaziwin database project. vi + 106 p.

Return to footnote 98

Footnote 99

Lutsel K'e Dene Elders, Ellis, S., Catholique, B., Desjarlais, S., Catholique, B., Catholique, H., Basil, M., Casaway, N., Catholique, S. and Lockhart, J. 2002. Traditional knowledge in the Kache Tué study region: phase three - towards a comprehensive environmental monitoring program in the Kakinÿne region - final report. Lutsel K'e Dene First Nation. 86 p.

Return to footnote 99

Footnote 100

 Fraser, M., Cuerrier, A., Haddad, P.S., Arnason, J.T., Owen, P.L. and Johns, T. 2007. Medicinal plants of Cree communities (Quebec, Canada): antioxidant activity of plants used to treat type 2 diabetes symptoms. Canadian Journal of Physiology and Pharmacology 85:1200-1214.

Return to footnote 100

Footnote 101

Woodward, K.E. 1999. Contemporary Cree art in northern Quebec: a northern artist's look at the impact of James Bay hydroelectric development on the art and craft of the James Bay Cree. In Social and environmental impacts of the James Bay hydroelectric project. Edited by Hornig, J.F. McGill-Queen's University Press. Montréal, QC. Chapter 7. pp. 141-158.

Return to footnote 101

Footnote 102

Tremblay, M., Furgal, C., Larivée, C., Annanack, T., Tookalook, P., Qiisik, M., Angiyou, E., Swappie, N., Savard, J.-P. and Barrett, M. 2008. Climate change in northern Quebec: adaptation strategies from community-based research. Arctic 61:27-34.

Return to footnote 102

Footnote 103

Dumont, C., Girard, M., Bellavance, F. and Noel, F. 1998. Mercury levels in the Cree population of James Bay, Quebec, from 1988 to 1993/94. Canadian Medical Association Journal 158:1439-1445.

Return to footnote 103

Footnote 104

Rosenberg, D.M., Berkes, F., Bodaly, R.A., Hecky, R.E., Kelly, C.A. and Rudd, J.W.M. 1997. Large-scale impacts of hydroelectric development. Environmental Reviews 5:27-54.

Return to footnote 104

Footnote 105

Harvey, W.F. and Rodrigue, J. 2009. A breeding pair survey of Canada geese in northern Quebec - 2009. Maryland Department of Natural Resources and Canadian Wildlife Service. 12 p.

Return to footnote 105

Footnote 106

Peloquin, C. and Berkes, F. 2009. Local knowledge, subsistence harvests, and social-ecological complexity in James Bay. Human Ecology 37:533-545.

Return to footnote 106

Footnote 107

Peloquin, C. 2007. Variability, change and continuity in social-ecological systems: insights from James Bay Cree cultural ecology. Thesis (Master of Natural Resources Management). University of Manitoba, Natural Resources Institute. Winnipeg, MB. 155 p.

Return to footnote 107

Footnote 108

InterGroup Consultants Ltd. 2008. Economic valuation and socio-cultural perspectives of the estimated harvest of the Beverly and Qamanirjuaq caribou herds. Beverly and Qamanijuaq Caribou Management Board. Stonewall, MB. 28 p. + 3 appendices.

Return to footnote 108

Return to Table of Contents

Theme: Habitat, Wildlife and Ecosystem Processes

 

Intact landscapes and waterscapes

 
Theme Habitat, wildlife, and ecosystem processes

Intact landscapes and waterscapes was initially identified as a nationally recurring key finding and information was subsequently compiled and assessed for the Taiga Shield Ecozone+. In the final version of the national report,Footnote 3 information related to intact landscapes and waterscapes was incorporated into other key findings. This information is maintained as a separate key finding for the Taiga Shield Ecozone+.

Within the boundaries of the Taiga Shield Ecozone+, there is a relatively low level of human disturbance. Human settlements are thinly scattered, industrial development is comparatively low, and the road network is sparse. At the current rate of human activity, habitat changes are site-specific and local. However, their cumulative footprint is increasing and concerns are growing. For example, the Dene First Nations near Great Slave Lake report that caribou locations have shifted from the past and that the animals are avoiding areas inhabited by people.Footnote 54

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Species of special economic, cultural, or ecological interest

Key finding 17
Theme Habitat, wildlife, and ecosystem processes

National key finding
Many species of amphibians, fish, birds, and large mammals are of special economic, cultural, or ecological interest to Canadians. Some of these are declining in number and distribution, some are stable, and others are healthy or recovering.

Migratory tundra caribou

This section is based on the report on Northern caribou population trends in Canada,Footnote 12 a technical thematic report prepared for the 2010 Ecosystem Status and Trends Report. As per this report, Northern caribou include migratory tundra caribou of three sub-species: barren-ground caribou (Rangifer tarandus groenlandicus) which range east of the McKenzie River, Grant's caribou (R. t. granti), which range west of the Mackenzie River, and woodland caribou (forest-tundra population) (R. t. caribou) comprised of two large herds in Ungava and two small herds that calve along the south coast of Hudson Bay).

Migratory tundra caribou are a pivotal species ecologically, as well as for people, so their distribution is well monitored through aerial surveys or satellite telemetry. Caribou use the Taiga Shield mainly from fall to spring, although the areas they use vary from year to year. Migratory caribou numbers have generally declined since peak abundance in the mid-1990s – and some have declined severely in recent years. The declines may be part of natural cycles, perhaps augmented by cumulative effects from stressors including climate change, harvest pressures, and increasing human presence on parts of the ranges. Highs and lows in historic abundance since the 1800s have been reconstructed from the frequency of hoof scars on spruce roots for the Bathurst and George River herds.Footnote 109 Footnote 110

The following herds – all in decline in 2010 – use significant parts of the western Taiga Shield over their annual cycle (Figure 26): Bathurst (Figure 27), Beverly (Figure 28), and Qamanirjuaq (Figure 29). The Bluenose East herd increased from 2006 to 2010Footnote 12 but declined in 2013.Footnote111 The status of the Lorillard Herd is unknown and the Ahiak Herd is declining based on preliminary data. In the eastern Taiga Shield, the George River Herd (Figure 30) summers and winters in the ecozone+. The Leaf River Herd (Figure 31) uses the area in winter only. Both herds are in decline.

Figure 26: Distribution and status of migratory tundra caribou herds with ranges extending into the Taiga Shield Ecozone+
Map
Source: Gunn et al., 2011Footnote 12 Bluenose East Herd information updated with 2013 census information from Government of Northwest Territories Environment and Natural ResourcesFootnote111
Long description for Figure 26

This map presents the distribution and status (increasing or decreasing) of caribou herds in the Taiga Shield Ecozone+. Most of the caribou herds in the ecozone+ are decreasing in population size, including the Bathurst, Beverly, and George River herds. The Leaf River, Qamanirjuaq and Bluenose-east caribou herds also show evidence of decline, but are not well studied. The Ahiak herd also shows evidence of decline, based on preliminary data. The status of the Lorillard Caribou Herd is also unknown. The Cape Churchill Caribou Herd is considered stable.

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Figure 27. Bathurst Caribou Herd population estimates, 1977-2009.
Graph
Source: Gunn et al., 2011Footnote 12
Long description for Figure 27

This bar graph shows the following information:

Bathurst
YearBathurst

Calving-ground photo survey
Bathurst

Visual calving-ground survey
Bathurst

Standard error
1977-160,000-
1978-127,000-
1980140,000140,000-
1982174,000--
1984384,000-65,000
1986472,000-72,900
1990351,683-77,800
1996349,046-94,900
2003186,005-40,146
2006128,047-24,000
200931,900-6,270

The Bathurst Herd uses the Taiga Shield in fall and winter. The historical trend, based on Tlicho elders' recollections of enough caribou in fall hunting camps, was high numbers in 1940s, low in the 1950s and increasing during the 1970s and 1980s. Since 1998, the southern boundary of the winter range has contracted.

Figure 28. Beverly Caribou Herd population estimates, 1971-2008.
Graph
Source: Gunn et al., 2011Footnote 12
Long description for Figure 28

This bar graph presents the following information:

Beverly
YearBeverly

Calving-ground photo survey
Beverly

Visual calving-ground survey
Beverly

Standard error
1971-210,000-
1978-130,000-
1980-105,000-
1982164,338-72,332
1984263,691-80,652
1988189,561-70,961
199387,000-17,900
1994276,000-106,600

The Taiga Shield provides fall and winter range for the Beverly Herd. The herd's trends in abundance and vital rates were not monitored between 1994 and 2008. However, a 2002 systematic reconnaissance survey reported lower densities than in 1994. Four calving ground delineation surveys from 2006 to 2009 also found few cows and even fewer calves. This information suggests a declining population. However, population estimates were unable to be determined from this data and are not shown in Figure 28.

Figure 29. Qamanirjuaq Caribou Herd population estimates, 1976-2008.
Graph
Source: Gunn et al., 2011Footnote 12
Long description for Figure 29

This bar graph presents the following information:

Qamanirjuaq
YearQamanirjuaq

Calving-ground photo survey
Qamanirjuaq

Visual calving-ground survey
Qamanirjuaq

Standard error
1976-43,800-
1977-44,095-
1980-39,000-
1982-180,000-
1983230,000-59,000
1985272,000-142,000
1988221,000-72,000
1994495,665-105,426
2005---
2006---
2007---
2008348,661-44,861

The Taiga Shield is fall and winter range for the Qamanirjuaq Herd. Numbers were very low in the 1970s and increased until at least 1994. Nunavut completed a calving ground survey in 2008 and determined the herd had declined but that the trend was not statistically significant.Footnote 112

Figure 30. George River Caribou Herd population estimates.
Graph
Source: Gunn et al., 2011Footnote 12
Long description for Figure 30

This bar graph presents the following information:

George River
YearGeorge River

Calving-ground
photo survey
George River

Visual calving-ground survey
George River

Post calving
photo survey
George River

90% CI
1973-105,000--
1975-205,000--
1976-263,100--
1980-390,100--
1982-360,450--
1984644,000--161,644
1993775,891--103,969
2001--385,000108,000
2010--74,13112,602

The herd increased from the 1950s to the mid-1990s. Degradation of summer habitat may have facilitated the decline to 74,100 individuals in 2010.

Figure 31. Leaf River Caribou Herd population estimates 1975-2001.
Graph
Source: Gunn et al., 2011Footnote 12
Long description for Figure 31

This bar graph presents the following information:

Leaf River
YearLeaf River

Calving-ground
photo survey
Leaf River

Visual calving-ground survey
Leaf River

Post calving
photo survey
Leaf River

90% CI
1975-56,000--
1983-101,000-43,430
1986121,000--56,386
1991276,000--75,900
2001--628,000-

The Leaf River (Rivière-aux-Feuilles) Herd increased from 1975 to the last census in 2001. Observations of body condition and calf recruitment in 2007 and 2008 suggest the population has likely declined since 2001.

Boreal caribou

Woodland caribou, boreal population (i.e., boreal caribou) was listed as Threatened under the Species at Risk Act (SARA) in 2003.Footnote113 The classification of caribou used in this report follows the current Species at Risk Act (SARA) classification system. In 2011, COSEWIC adopted 12 designatable units for caribou in Canada that will be used in caribou assessments and subsequent listing decisions under SARA beginning in 2014. This section on boreal caribou is based on the 2011 Scientific Assessment to Inform the Identification of Critical HabitatFootnote114 and the 2012 Recovery Strategy for the Woodland Caribou (Rangifer tarandus caribou), boreal population in Canada.Footnote115 The information in this section has been updated since the release of the ESTR national thematic report, Woodland caribou, boreal population, trends in Canada.Footnote 13

Six boreal caribou local populations have ranges that are fully or partially in the Taiga Shield ecozone+. Very small portions of the range in the Northwest Territories and the range in Northern Saskatchewan, both with unavailable population trends, occur in the western Taiga Shield.Footnote 13 In the eastern Taiga Shield, four local populations extend across the south of the ecozone+. The Quebec local population is considered stable; the three local populations in Labrador are declining (Figure 32).

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Figure 32: Status of boreal caribou local populations in the Taiga Shield (east) Ecozone+.
Map
Source: updated from Callaghan et al., 2011,13 based on Environment Canada 2012Footnote115
Long description for Figure 32

This map presents the status of four caribou populations located in the Taiga Shield Ecozone+ in central Quebec and Labrador. The Quebec population is considered stable and the three in Labrador, Red Wine Mountain, Lac Joseph, and Mealy Mountain, are declining.

Broad-scale reduction of range and population declines of boreal caribou in Canada are associated with loss and degradation of mature coniferous forest habitat.Footnote 13 The most immediate effect of this reduction in mature forest is an increase in younger forest types that favour other ungulates such as moose (Alces alces) and white-tailed deer (Odocoileus virginianus). This change in turn results in more predators and increased predation on caribou.Footnote114 Footnote127 Although deer are rare, their abundances are increasing and the distributions of moose are changing in the Taiga Shield (see Major range shifts in species native to Canada on page 56).

Human disturbances (right of ways, for example), will also facilitate predator movement. This increases the risk of predation by increasing predator-caribou encounter rates.Footnote128 Boreal caribou are closely associated with late-successional coniferous forests and peatlandsFootnote129 that function as refugia, away from high densities of predators and their alternate prey.Footnote 120 Footnote 122 Footnote 124 Footnote 130 Footnote 131

The extent of hunting is poorly understood in most areas. Analyses of historical population trends, data from radio-collared animals, and current demographic information indicate that hunting remains an important component of adult female boreal caribou mortality and hence is a primary threat to some local populations.Footnote132 In Labrador, harvest by humans is the most significant threat to boreal caribou.Footnote 13 Hunting of boreal caribou by humans and predators, such as wolves, is facilitated by construction of roads and other linear features and by use of off-road vehicles that permit access to previously inaccessible areas.Footnote128

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Waterfowl

This section is based on Trends in breeding waterfowl in Canada,10 a technical thematic report prepared for the 2010 Ecosystem Status and Trends Report. Analyses of trends by ecozone+ in the waterfowl report included data up to 2006 and have not been updated here.
Scaup (Aythya spp.), American wigeon (Anas americana), and scoters (Melanitta spp.) are experiencing population declines in the western part of the Taiga Shield (Figure 33). Declining trends were also reported for neighbouring ecozones+ for most of these species, suggesting common factors are at work. Climate change may be driving at least some of these declines. Lesser scaup (A. affinis), white-winged scoters (M. deglandi) and American wigeon are relatively late nesters,Footnote 133 Footnote 134 Footnote 135 and DeVink et al. Footnote136 suggest that, if there is a dependence on photoperiod as a breeding cue, there may be a growing mismatch between timing of nesting and food availability. The availability of their invertebrate food source may be shifting with changing temperatures, resulting in decreased hen and duckling survival.

Figure 33. Western Taiga Shield Ecozone+ population trends for bufflehead, scaup, American widgeon and scoter, 1970-2006.
Changes are significant (p<0.05) for species marked with an asterisk. Species: scaup, American wigeon, and scoters
Graph
Source: Fast et al. 2011Footnote 10
Long description for Figure 33

This graphic is composed of two graphs: a bar graph showing the following information:

Change in abundance, 1970 to 2006
SpeciesPercentage
bufflehead-2%
scaup*-63%
American wigeon*-54%
scoter*-41%

and a line graph showing the following information:

YearBreeding pairs
1970692,043
1971777,289
19721,422,897
1973946,024
1974696,938
1975944,467
1976828,456
1977790,675
1978745,274
1979750,516
1980790,896
1981730,862
1982594,214
1983654,698
1984731,253
1985629,319
1986564,267
1987424,462
1988446,308
1989479,752
1990321,850
1991429,336
1992233,236
1993371,036
1994354,962
1995411,637
1996269,117
1997270,598
1998377,277
1999482,308
2000301,344
2001249,438
2002301,018
2003520,291
2004392,460
2005251,142
2006216,782

Surveys since 1991 in the eastern Taiga Shield ecozone+ show considerable year-to-year variation, but the trends suggest stable population levels for ring-necked duck (Aythya collaris), scaup , American black duck (Anas rubripes), and green-winged teal (Anas carolinensis) (Figure 34).

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Figure 34: Number of breeding pairs of American black duck, green-winged teal, scaup (Aythya affinis and A. marila combined), and ring-necked duck in the Eastern Taiga Shield ecozone+, 1990-2006. There were no significant trends.
Graph
Source: Fast et al. 2011Footnote 10
Long description for Figure 34

This multiple line graph shows the following information:

Number of breeding pairs
YearAmerican Black DuckGreen-winged TealScaupRing-necked Duck
199012,4541,2209,0512,089
199110,2884,2691,8101,492
19927,9423,28200
19932,1660905298
19948,1322,1289052,387
199510,1393,8291,418358
19966,9043,4443,1082,159
19974,1192,4051,8641,267
19984,4701,9761,821694
19997,4993,7531,4781,606
20008,3812,6101,1231,297
20017,3404,01901,389
20028,4306,1983,809723
20035,4904,9101,7981,056
20047,5947,8861,1122,530
20054,5744,0191,9541,215
20064,6012,1425,377668

Landbirds

Because few data were available for landbirds breeding in the taiga, landbird information was combined for all taiga ecozones+.Footnote 14 Populations of some species are monitored on their wintering ranges in the United States and southern Canada through the Christmas Bird Count (CBC). North American trends are shown below (Table 6) for six landbird species with breeding ranges that included portions of the three taiga ecozones+. Canada has a high stewardship responsibility for all of these species because large portions of their western hemisphere breeding populations are in Canada.

Table 6: Trends in annual abundance of selected landbirds from the three taiga ecozones+, 1966-2005
SpeciesMain breeding
range
Population trend
(%/yr)
PCBCAI
1970s
CBCAI
1980s
CBCAI
1990s
CBCAI
2000s
CBCAI
Change
Rusty blackbird(Euphagus carolinus)Hudson Bay Lowlands,
taiga and boreal
-5.46%*1.50.70.40.3-78%
Boreal chickadee (Poecile hudsonicus)Taiga and boreal-1.73%*1.61.31.21.2-29%
Northern shrike (Lanius excubitor)Taiga-0.79%*1.11.01.00.8-29%
Pine grosbeak (Pinicola enucleator)Taiga and boreal-0.78%5.13.42.82.5-52%
Smith's longspur (Calcarius pictus)Taiga-0.32% -0.050.060.070.0857%
Lincoln's sparrow (Melospiza lincolnii)Taiga and boreal-0.08% -1.51.51.71.68%

Source: based on data from the Christmas Bird Count (courtesy of D. Niven, Audubon) as reported in Downes et al., 2011Footnote 14

Table 6 description

Shown are the annual rate of change and the average CBC abundance index by decade. Asterisks (*) indicate statistically significant trends (P<0.05).

Three of six species show statistically significant long-term declines. In particular, the rusty blackbird (Euphagus carolinus), a temperate migrant that winters in the United States, declined by 78% between the 1970s and the 2000s (Figure 35). This decline was supported by surveysFootnote137 from other parts of its range that showed an even steeper rate of decline for Canada overall. Circumstantial evidence suggests that declines have not been as dramatic in the north.Footnote138 The declines in boreal chickadee (Poecile hudsonicus) and pine grosbeak (Pinicola enucleator) were also supported by evidence of declines from surveys in other parts of their breeding ranges.Footnote 14

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Figure 35: Trend in annual abundance index for the rusty blackbird
The decline is statistically significant (p<0.05).
Graph
Source: based on data from the Christmas Bird Count (courtesy of D. Niven, Audubon) as reported in Downes et al., 2011Footnote 14
Long description for Figure 35

This line graph depicts the following information:

YearAbundance Index
19662.74
19672.42
19682.28
19692.19
19701.80
19712.12
19721.69
19731.68
19741.42
19751.40
19761.34
19771.26
19781.05
19790.93
19801.05
19810.86
19820.89
19830.89
19840.63
19850.72
19860.63
19870.63
19880.51
19890.59
19900.50
19910.44
19920.46
19930.40
19940.35
19950.40
19960.38
19970.32
19980.41
19990.35
20000.36
20010.28
20020.34
20030.34
20040.31
20050.31

Fish

Information about general fish health from Aboriginal Traditional Knowledge in the western portion of the Taiga Shield shows varying changes. The Dene report fewer fish in the Mackenzie River areaFootnote139 and near Great Slave Lake, while other reports say fish populations in Great Slave Lake are at least as good as in the past.Footnote 54 Footnote 84 Footnote 140 In the Hudson Bay region, there are reports that fish behaviour and health have changed, that migration patterns have altered, and that dams and changing water levels stop fish moving upstream and into lakes.Footnote 88

In the eastern portion of the Taiga Shield, hydroelectric development has had a dramatic impact on a number of river basins. Changes affecting fish are discussed under Dams and reservoirs on page 23.

Vascular plants

Aboriginal peoples report many local changes in vegetation, for example:

  • Anaktalak Bay area of Nunutsiavut (south of Nain), 2007: an increase in the growth and abundance of some plants, such as berries, that are good for food.Footnote 85
  • Wemindji, James Bay, 2005: terrestrial vegetation is replacing aquatic vegetation, and willows and other shrubs cover previously bare ground. Both changes have impacts on geese. In areas that previously grew berries, trees now grow.Footnote 57
  • Near Great Slave Lake, 2002: pin cherries, trees that commonly grow on disturbed ground, appeared after a new road was built.Footnote 99

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Major range shifts in species native to Canada

Range extensions to the Taiga Shield ecozone+ from ecozones+ to the south have been noted in some areas since the 1960s. Newly arrived species include: white-tailed deer in the NWTFootnote141 and Alberta,Footnote142 coyote (Canis latrans) in the NWTFootnote143 and Labrador, Footnote144 wood bison (Bison bison athabascae),Footnote143 and magpies (Pica pica).Footnote145

Several range shifts have been directly associated with human activities.143 White-tailed deer, coyote, and wood bison likely followed the Yellowknife highway corridor northward into the Taiga Shield.Footnote146 Elders report that when bison populations were high in the Slave River Lowlands (Taiga Plains ecozone+), there was some westward spillover into the Taiga Shield, but because habitat patches were small, the animals would not stay.146 Some species, such as coyote and magpie rarely venture beyond the Yellowknife city limits.Footnote145, Footnote146 Climate change is expected to make larger areas more hospitable to new arrivals and these and other species may spread further.Footnote 147 Footnote 148

Photo: James Sangris with a white-tailed deer doe harvested at Wool Bay, Great Slave Lake, western
Photo: James Sangris with a white-tailed deer
Taiga Shield, October 2007. © GNWT-D. Cluff

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Range changes are often noticed first by local residents and hunters and observations of unusual animal sightings are an important way to track species distribution changes.Footnote142 Some examples of range change information based on local knowledge: Range expansion or vagrancies from the north into the western Taiga Shield have been noted for grizzly bear (Ursus arctos) and muskoxen (Ovibos moschatus).Footnote142, Footnote145 The Dene First Nation reported an increase in moose and bears along the tree line in the Artillery Lake area.Footnote140 Along the Labrador coast Inuit have observed moose (around Anaktalak Bay) and consider that they are moving northward because of climate change.Footnote 85 The communities of eastern James Bay have observed a decrease in moose and moose habitat and a decline in moose body condition.Footnote 86 Footnote 149

Primary productivity

Key finding 18
Theme Habitat, wildlife, and ecosystem processes

National key finding
Primary productivity has increased on more than 20% of the vegetated land area of Canada over the past 20 years, as well as in some freshwater systems. The magnitude and timing of primary productivity are changing throughout the marine system.

This section is based on analyses and interpretations in Monitoring biodiversity remotely: a selection of trends measured from satellite observations of Canada.Footnote 16 Additional material has been added on the relationship between primary productivity and forest fires.

Over 36% of the land area of the Taiga Shield ecozone+ showed a significant increase in NDVI (an index related to primary productivity, derived from remote sensing) from 1986-2006 (Figure 36). Less than 1% of the land showed a decreasing trend. The increase in this ecozone+, one of the highest in Canada,Footnote 16 was strongest in the east, especially south of Ungava Bay (an area dominated by tundra vegetation), and also in southern Labrador (conifer forest and shrubland). The NDVI in the area between these two "hotspots" also exhibited a positive but less pronounced trend. NDVI increased in large parts of the northern portion of the western Taiga Shield. This area, characterized by the most productive soil in the western Taiga Shield,Footnote 22 is predominantly covered with conifer forests, but shrub and tundra vegetation are also well represented.

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Figure 36: Trend in Normalized Difference Vegetation Index (NDVI), Taiga Shield ecozone+, 1985-2006
Trends are in annual peak NDVI, measured as the average of the 3 highest values from 10-day composite images taken during July and August of each year. Spatial resolution is 1 km, averaged to 3 km for analysis. Only points with statistically significant changes (p<0.05) are shown.
Map
Source: NDVI trend analysis by Pouliot et al., 2009;Footnote150 ecozone+ analysis by Ahern et al., 2011Footnote 16
Long description for Figure 36

This map presents significant differences in annual peak Normalized Difference Vegetation Index (NDVI) for the eastern and western parts of the Taiga Shield Ecozone+. These data are presented as units of area that have increased or decreased in NDVI between 1985 and 2006. Across the ecozone+, 36% of the land area experienced a significant increase in NDVI, and more of the land area experiencing increases was in the eastern Taiga Shield. Increased NDVI in the western Taiga Shield was more prevalent in the northwest part of the ecozone+, and the large majority of land with decreased NDVI (<1% of total area) were in the western part of the ecozone+.

Pouliot et al. (2009)Footnote150 found that burns can have positive, negative, and zero NDVI trends, depending on the age of the burn. For example, an analysis of burned and unburned sites in the boreal forest of central CanadaFootnote151 found significant increases in NDVI at all sites with fires since 1984 and at 50% of unburned sites. Fire cannot, however, account for all the substantive increase in NDVI in the Taiga Shield – a comparison of the NDVI trend map with the map of large fires since the 1980s (Figure 37) shows that the main areas of increased NDVI are not areas that have recently burned. The areas in the western Taiga Shield showing negative NDVI trends may be recently burned black spruce-lichen woodland occupying poor soils. On better soils, lichen does not compete well with vascular understory plants. After fire in spruce-lichen woodland, soil surfaces may remain blackened for many years as black spruce and lichen are very slow to recover.Footnote 145 Footnote 146

Figure 37: Locations of large fires by decade, 1980s to 2000s
Map
Source: Krezek-Hanes et al., 2011Footnote 8
Long description for Figure 37

This map shows the locations of fires in the Taiga Shield Ecozone+, by decade. The eastern part of the Taiga shield experienced large burns in the 1980s in the area near James Bay, and fewer fires in later decades. In the western Taiga Shield, the fires were prevalent in the 1980s and 1990s, and concentrated in the central-southern part of the ecozone+. Fires in the 2000s are distributed more sparsely across the ecozone+.

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Natural disturbance

Key finding 19
Theme: Habitat, wildlife, and ecosystem processes

National key finding
The dynamics of natural disturbance regimes, such as fire and native insect outbreaks, are changing and this is reshaping the landscape. The direction and degree of change vary.

Fire, weather extremes, and diseases shape and modify the flora and fauna of the Taiga Shield Ecozone+. Disturbances such as forest fires tend to be small and frequent or large and rare, and so the calculation of trends of disturbances requires longer temporal datasets. Other than data on forest fires, relatively little specific information has been compiled for the Taiga Shield.

Fire trends

This section is based on analyses and interpretations in Trends in large fires in Canada, 1959-2007.Footnote 8 and Monitoring biodiversity remotely: a selection of trends measured from satellite observations of Canada.Footnote 16

The fire regime in the Taiga Shield is characterized by large, severe fires.Footnote 152 Footnote 153 Footnote 154 Trees and other plants in the Taiga Shield evolved in a fire environment and a changing fire regime will impact the distribution of species and plant communities. For example, fire plays a stronger role than climate in determining the northern limit of jack pine (Pinus banksiana).Footnote155

The area burned in the Taiga Shield (Figure 38) increased from the 1960s until the 1990s, a trend attributed to changes in detection methods and warmer temperatures.Footnote 156 Footnote 157 The decline since the 1990s is similar to the pattern shown for the Taiga Plains ecozone+, and the magnitude of the decline is the same as changes between previous decades. The decline may be related to large atmospheric oscillations.Footnote 8

Figure 38: Trend in total area burned per decade in the Taiga Shield ecozone+, 1960s-2000s
The value for the 2000s decade was pro-rated over 10 years based on the 2000-2007 average.
Graph
Source: Krezek-Hanes et al., 2011Footnote 8
Long description for Figure 38

This bar graph illustrates the following information:

DecadeTotal area burned (km2)
1960s6,003
1970s36,338
1980s46,575
1990s69,305
2000s34,283

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The average duration of the active fire season, about 75 days, has not changed significantly over the period of record (Figure 39).Footnote 8 Fires occur most commonly between June and August, peaking in July, but there was a significant increase in May fires from the 1960s to the 1990s. Few May fires were recorded, however, and the record is relatively short. There are no comparable records, for example, for fires in the warm, dry decade of the 1940s, which may have experienced fires in May. Fires in the eastern portion of the Taiga Shield generally occurred earlier than fires in the west.Footnote158

Figure 39: The proportion of large fires that occur in each month of the fire season by decade.
This fire trend is based on the number of large fires (over 200 ha in size). Monthly numbers are the percentage of the total number of fires that occurred during the month.
clustered bar chart
Source: Krezek-Hanes et al., 2011Footnote8
Long description for Figure 39

This clustered bar chart shows the following information:

DecadePercent
May
Percent
June
Percent
July
Percent
August
Percent
September
Days
Average Duration
1960s0355411147
1970s1285713185
1980s2185227284
1990s2323926191

Lightning causes, on average, 92% of large fires in the Taiga Shield. The proportion of fires caused by lightning has increased over the last 40 years due to a decrease in human-caused fires. The absolute number of fires caused by lightning also increased over the same time period, although this increase was not statistically significant.Footnote 8

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Insect outbreaks

There is little information on insect outbreaks specific to the Taiga Shield. In the eastern Taiga Shield, insect disturbance seems to play a less important role than in the drier northwestern part of the continent.Footnote159

The spruce bark beetle (Dendroctonus rufipennis), the main pest affecting white spruce at the north of its distribution, appears to occur sporadically in the eastern Taiga Shield. A large section of lowland forest along Napaktok Bay, Labrador experienced severe tree mortality from 1989 to 1991, likely caused by an outbreak of spruce bark beetles.Footnote 27 Tree-ring analyses in the Kuujjuarapik region of James Bay found low levels of spruce bark beetle activity, but without regional outbreaks, extending back about 400 years (the age of the trees).Footnote159 At one of the three study sites, an outbreak resulted in extensive tree mortality in the late 20th century.

Outbreaks of the spruce bark beetle may become more significant in the Taiga Shield in the future as summer and winter temperatures increase. Outbreaks are normally associated with forest disturbances such as windthrow, fire, or land clearing. A severe, recent outbreak in the Boreal Cordillera ecozone+, however has been attributed to an increase in drying out of spruce trees in the summer (making the trees more vulnerable to bark beetle attack) and to increased beetle reproductive success in the warmer summers along with decreased beetle mortality in the milder winters.Footnote160

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Food webs

Key finding 20
Theme: Habitat, wildlife, and ecosystem processes

National key finding
Fundamental changes in relationships among species have been observed in marine, freshwater, and terrestrial environments. The loss or reduction of important components of food webs has greatly altered some ecosystems.

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Population cycles

Detecting changes in ecosystems dominated by seasonality and climate variability generally requires long-term monitoring, which is rare in this ecozone+. The low level of species diversity means that both predators and herbivores are vulnerable to fluctuations in the abundance of their food supplies, accentuating the natural pulses in the ecosystem. Most mammals in the Taiga Shield have cyclic dynamics. The principal exceptions are large-bodied mammals, such as moose and muskoxen. The latter are at the edge of their range in the Taiga Shield, but are increasing in the ecozone+.Footnote145

Variations in high densities of snowshoe hare populations have been linked with variations in fire frequencies across their range in North America. Fires create abundant early succession plants that are eaten by hares in winter.Footnote161 The highest densities of snowshoe hares in peak years have been measured where fire frequencies are the highest, including in the western Taiga shield.Footnote162

An increasing body of evidence identifies climate variables, especially snow and winter temperatures, as drivers in cyclic dynamics. For example, a decreasing amplitude of cyclic dynamics and collapse of cycles are reported for voles, grouse, and the larch budmoth (Zeiraphera diniana) in northern Fennoscandia, coinciding with climatic change.Footnote163 The variability in the amplitude of small mammal cycles in the Taiga Shield (Figure 40), however, means that detecting trends requires a longer series of data than is currently available.

Figure 40: Snowshoe hare density at three sites in the western Taiga Shield, 1988-2008
Data were missing for 1997 and 1998; according to local knowledge numbers were increasing rapidly during these years.
Graph
Source: Data provided by S. Carrière, Government of the Northwest Territories. Photo © iStock.com
Long description for Figure 40

This line graph shows the estimated density of snowshoe hares in the Taiga shield in the Northwest Territories between 1988 and 2008. Density at the Yellowknife and Yukon River is variable, and experienced a low of <1 hare/ha in 1994, but was very high (>5 hares/ha) in 1999 (data were not available for 1997-98). A major drop in hare density occurred between 1999 and 2003, with a trend for gradual increase into the late 2000s. The Gordon Lake and Tibbitt Lake sites were less variable, with fairly consistent levels of <1 hare/ha, though these data were only available from 2000 to 2008.

Migratory species

The Taiga Shield ecozone+ has a high proportion of migratory species. Most species that glean insects from foliage or hunt on the wing, including bats, migrate to southern ecozones+ in winter. Twenty-nine bird species use the boreal forest as a stopover during migration.Footnote164 The Taiga Shield is also the seasonal destination for migrants from more northern ecozones+, from ptarmigan (Lagopus sp.) to barren ground caribou.

There is much uncertainty about the implications and cascades of effects related to changes in population dynamics of migratory species. For example, many species of migratory insectivorous birds are declining, some due to changes in their winter ranges. How these declines are linked to the population dynamics of their insect prey and how they might influence insect outbreaks and tree health in the Taiga Shield are unknown, though these chains of effects have been demonstrated in other regions.Footnote 165 Footnote 166

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Footnotes

Footnote 3

Federal, Provincial and Territorial Governments of Canada. 2010. Canadian biodiversity: ecosystem status and trends 2010. Canadian Councils of Resource Ministers. Ottawa, ON. vi + 142 p.

Return to footnote 3

Reference 8

Krezek-Hanes, C.C., Ahern, F., Cantin, A. and Flannigan, M.D. 2011. Trends in large fires in Canada, 1959-2007. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 6. Canadian Councils of Resource Ministers. Ottawa, ON. v + 48 p.

Return to footnote 8

Reference 10

Fast, M., Collins, B. and Gendron, M. 2011. Trends in breeding waterfowl in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 8. Canadian Councils of Resource Ministers. Ottawa, ON. v + 37 p.

Return to footnote 10

Reference 12

Gunn, A., Russell, D. and Eamer, J. 2011. Northern caribou population trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 10. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 71 p.

Return to footnote 12

Reference 13

Callaghan, C., Virc, S. and Duffe, J. 2011. Woodland caribou, boreal population, trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 11. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 36 p.

Return to footnote 13

Reference 14

Downes, C., Blancher, P. and Collins, B. 2011. Landbird trends in Canada, 1968-2006. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 12. Canadian Councils of Resource Ministers. Ottawa, ON. x + 94 p.

Return to footnote 14

Reference 16

Ahern, F., Frisk, J., Latifovic, R. and Pouliot, D. 2011. Monitoring ecosystems remotely: a selection of trends measured from satellite observations of Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 17. Canadian Councils of Resource Ministers. Ottawa, ON.

Return to footnote 16

Footnote 22

Timoney, K.P. 1995. Tree and tundra cover anomalies in the Subarctic forest-tundra of northwestern Canada. Arctic48:13-21.

Return to footnote 22

Footnote 27

Payette, S. 2007. Contrasted dynamics of northern Labrador tree lines caused by climate change and migrational lag. Ecology88:770-780.

Return to footnote 27

Footnote 54

Lutsel K'e Dene First Nation, Parlee, B., Basil, M. and Casaway, N. 2001. Final report: Traditional Ecological Knowledge in the Kaché Tué study region. Lutsel K'e Dene First Nation. 87 p.

Return to footnote 54

Footnote 57

Bussières, V. 2005. Towards a culturally-appropriate locally-managed protected area for the James Bay Cree community of Wemindji, northern Québec. Thesis (Master of Public Policy and Public Administration). Concordia University, Department of Geography, Planning and Environment. Montréal, QC. 125 p.

Return to footnote 57

Footnote 84

Lutsel K'e Dene Community Members, Krieger, M., Catholique, H., Drygeese, D., Casaway, N., Lantz, A., Desjarlais, P., Boucher, E., Michel, P., Catholique, S., Lockhart, J. and Catholique, L. 2005. Ni hat'ni - watching the land: results of 2003-2005 monitoring activities in the traditional territory of the Lutsel K'e Denesoline - final report. Lutsel K'e Dene First Nation. 109 p.

Return to footnote 84

Footnote 85

Davies, H. 2007. Inuit observations of environmental change and effects of change in Anaktalak Bay, Labrador. Thesis (Master of Environmental Studies). Queen's University, School of Environmental Studies. Kingston, ON. 156 p.

Return to footnote 85

Footnote 86

McDonald, M., Arragutainaq, L. and Novalinga, Z. (compilers). 1997. Voices from the bay: Traditional Ecological Knowledge of Inuit and Cree in the Hudson Bay bioregion. Canadian Arctic Resources Committee and Environmental Committee of the Municipality of Sanikiluaq. Ottawa, ON. xiii + 98 p.

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Footnote 88

Municipality of Sanikiluaq and Nunavuummi Tasiujarjuamiuguqatigiit Katutjiqatigiingit (NTK). 2008. Community Environmental Monitoring Systems (CEMS) workshop summary report, January 17, 2008-January 21, 2008. Update of Voices from the Bay. Municipality of Sanikiluaq. Sanikiluaq, NU. 41 p.

Return to footnote 88

Lutsel K'e Dene Elders, Ellis, S., Catholique, B., Desjarlais, S., Catholique, B., Catholique, H., Basil, M., Casaway, N., Catholique, S. and Lockhart, J. 2002. Traditional knowledge in the Kache Tué study region: phase three - towards a comprehensive environmental monitoring program in the Kakinÿne region - final report. Lutsel K'e Dene First Nation. 86 p.

Return to footnote 99

Footnote 109

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Payette, S., Boudreau, S., Morneau, C. and Pitre, N. 2004. Long-term interactions between migratory caribou, wildfires and Nunavik hunters inferred from tree rings. Ambio 33:482-486.

Footnote 110

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Zalatan, R., Gunn, A. and Henry, G.H.R. 2006. Long-term abundance patterns of barren-ground caribou using trampling scars on roots of Picea mariana in the Northwest Territories, Canada. Arctic, Antarctic, and Alpine Research 38:624-630.

Footnote 111

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Environment and Natural Resources. 2014. Bluenose East Herd [en ligne]. Government of Northwest Territories. (consulté le 5 Jan. 2014).

Footnote 112

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Campbell, M. 2008. Personal communication. Department of Environment, Government of Nunavut.

Footnote 113

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COSEWIC. 2002. COSEWIC assessment and update status report on the woodland caribou Rangifer tarandus caribou in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa, ON. xi + 98 p.

Footnote 114

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Environment Canada. 2011. Scientific assessment to inform the identification of critical habitat for woodland caribou (Rangifer tarandus caribou), boreal population, in Canada: 2011 update. Environment Canada. Ottawa, ON. xiv + 103 p.

Footnote 115

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Environment Canada. 2012. Recovery strategy for the woodland caribou (Rangifer tarandus caribou), boreal population, in Canada. Species at Risk Act Recover Strategy Series. Environment Canada. Ottawa, ON. xi + 138 p.

Footnote 122

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Rettie, W.J. and Messier, F. 1998. Dynamics of woodland caribou populations at the southern limit of their range in Saskatchewan. Canadian Journal of Zoology 76:251-259.

Footnote 124

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Racey, G.D. and Armstrong, T. 2000. Woodland caribou range occupancy in northwestern Ontario: past and present. Rangifer 12:173-184.

Footnote 127

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Vors, L.S., Schaefer, J.A., Pond, B.A., Rodgers, A.R. and Patterson, B.R. 2007. Woodland caribou extirpation and anthropogenic landscape disturbance in Ontario. Journal of Wildlife Management 71:1249-1256.

Footnote 128

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Whittington, J., Hebblewhite, M., DeCesare, N.J., Neufeld, L., Bradley, M., Wilmshurst, J. and Musiani, M. 2011. Caribou encounters with wolves increase near roads and trails: a time-to-event approach. Journal of Applied Ecology 48:1535-1542.

Footnote 131

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Bergerud, A.T. 1985. Antipredator strategies of caribou: dispersion along shorelines. Canadian Journal of Zoology 63:1324-1329.

Footnote 132

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Schmelzer, I., Brazil, J., Chubbs, T., French, S., Hearn, B., Jeffery, R., LeDrew, L., Martin, H., McNeill, A., Nuna, R., Otto, R., Phillips, F., Mitchell, G., Pittman, G., Simon, N. and Yetman, G. 2004. Recovery strategy for three woodland caribou herds (Rangifer tarandus caribou; boreal population) in Labrador. Department of Environment and Conservation, Government of Newfoundland and Labrador. Corner Brook, NL. 51 p.

Footnote 133

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Austin, J.E., Custer, C.M. and Afton, A.D. 1998. Lesser scaup (Aythya affinis). In The birds of North America online. Edited by Poole, A. Cornell Lab of Ornithology. Ithaca, NY. http://bna.birds.cornell.edu/bna/species/338.

Footnote 134

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Mowbray, T.B. 1999. American wigeon (Anas americana). In The birds of North America online. Edited by Poole, A. Cornell Lab of Ornithology. Ithaca, NY. http://bna.birds.cornell.edu/bna/species/401.

Footnote 135

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Brown, P.W. and Fredrickson, L.H. 1997. White-winged scoter (Melanitta fusca). In The birds of North America online. Edited by Poole, A. Cornell Lab of Ornithology. Ithaca, NY. http://bna.birds.cornell.edu/bna/species/274.

Footnote 136

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De Vink, J.M.A., Clark, R.G., Slattery, S.M. and Trauger, D.L. 2008. Are late-spring boreal lesser scaup (Aythya affinis) in poor body condition? Auk 125:297-298.

Footnote 137

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Breeding Bird Survey. 2008. North American Breeding Bird Survey [online]. U.S. Geological Survey, Patuxent Wildlife Research Center. http://www.pwrc.usgs.gov/bbs (accessed 23 October, 2009).

Footnote 138

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Machtans, C.S., Van Wilgenburg, S.L., Armer, L.A. and Hobson, K.A. 2007. Retrospective comparison of the occurrence and abundance of rusty blackbird in the Mackenzie Valley, Northwest Territories. Avian Conservation and Ecology/Écologie et conservation des oiseaux 2:1-14.

Footnote 139

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Cobb, D., Berkes, M.K. and Berkes, F. 2005. Ecosystem-based management and marine environmental quality in northern Canada. In Breaking ice: renewable resource and ocean management in the Canadian North. Edited by Berkes, F., Huebert, R., Fast, H., Manseau, M. and Diduck, A. University of Calgary Press. Calgary, AB. pp. 71-93.

Footnote 140

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Parlee, B., Manseau, M. and Lutsel K'e Dene First Nation. 2005. Understanding and communicating about ecological change: Denesoline indicators of ecosystem health. In Breaking ice: renewable resource and ocean management in the Canadian North. Edited by Berkes, F., Huebert, R., Fast, H., Manseau, M. and Diduck, A. University of Calgary Press. Calgary, AB. pp. 165-182.

Footnote 141

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Veitch, A.M. 2001. An unusual record of a white-tailed deer (Odocoileus virginianus) in the Northwest Territories. Canadian Field-Naturalist 15:172-175.

Footnote 142

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Latham, A.D.M., Latham, M.C., Nicole, A.M. and Boutin, S. 2011. Invading white-tailed deer change wolf-caribou dynamics in northeastern Alberta. Journal of Wildlife Management 75:204-212.

Footnote 143

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Hansell, R.I.C., Chant, D.A. and Weintrau, J. 1971. Changes in the northern limit of spruce at Dubawnt Lake, Northwest Territories. Arctic 24:233-234.

Footnote 144

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Chubbs, T.E. and Phillips, F.R. 2005. Evidence of range expansion of eastern coyotes, Canis latrans, in Labrador. Canadian Field-Naturalist 119:381-384.

Footnote 145

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Ecosystem Classification Group. 2008. Ecological regions of the Northwest Territories: Taiga Shield. Northwest Territories Department of Environment and Natural Resources. Yellowknife, NT. viii + 146 p.

Footnote 146

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Chowns, T.J. 2012. Personal communication. Written submission in review of the draft report.

Footnote 147

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Environment and Natural Resources. 2012. State of the Environment Report, Indicator 15.5. Change in wildlife distribution. [online]. Government of the Northwest Territories. (accessed January, 2013).

Footnote 148

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Environment and Natural Resources. 2008. NWT climate change impacts and adaptation report. Government of Northwest Territories. Yellowknife. 31 p.

Footnote 149

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Huntington, H.P., Fox, S., Berkes, F. and Krupnik, I. 2005. The changing Arctic: indigenous perspectives. In Arctic Climate Impact Assessment. Edited by Symon, C., Arris, L. and Heal, B. Cambridge University Press. New York, NY. Chapter 3. pp. 61-98.

Footnote 150

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Pouliot, D., Latifovic, R. and Olthof, I. 2009. Trends in vegetation NDVI from 1 km Advanced Very High Resolution Radiometer (AVHRR) data over Canada for the period 1985-2006. International Journal of Remote Sensing 30:149-168.

Footnote 151

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Alcaraz-Segura, D., Chuvieco, E., Epstein, H.E., Kasischke, E.S. and Trishchenko, A. 2010. Debating the greening vs. browning of the North American boreal forest: differences between satellite datasets. Global Change Biology 16:760-770.

Footnote 152

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Burton, P.J., Parisien, M.-A., Hicke, J.A., Hall, R.J. and Freeburn, J.T. 2008. Large fires as agents of ecological diversity in the North American boreal forest. International Journal of Wildland Fire 17:754-767.

Footnote 153

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Parisien, M.A., Peters, V.S., Wang, Y., Little, J.M., Bosch, E.M. and Stocks, B.J. 2006. Spatial patterns of forest fires in Canada, 1980-1999. International Journal of Wildland Fire 15:361-374.

Footnote 154

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Stocks, B.J., Mason, J.A., Todd, J.B., Bosch, E.M., Wotton, B.M., Amiro, B.D., Flannigan, M.D., Hirsch, K.G., Logan, K.A., Martell, D.L. and Skinner, W.R. 2003. Large forest fires in Canada, 1959-1997. Journal of Geophysical Research 108:8149-8161.

Footnote 155

Return to footnote 155

Asselin, H., Payette, S., Fortin, M.-J. and Vallée, S. 2003. The northern limit of Pinus banksiana Lamb. in Canada: explaining the difference between eastern and western distributions. Journal of Biogeography 30:1709-1718.

Footnote 156

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Gillett, N.P., Weaver, A.J., Zwiers, F.W. and Flannigan, M.D. 2004. Detecting the effect of climate change on Canadian forest fires. Geophysical Research Letters 31:L18211-.

Footnote 157

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Podur, J., Martell, D.L. and Knight, K. 2002. Statistical quality control analysis of forest fire activity in Canada. Canadian Journal of Forest Research/Revue canadienne de recherche forestière 32:195-205.

Footnote 158

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Kasischke, E.S. and Turetsky, M.R. 2006. Recent changes in the fire regime across the North American boreal region - spatial and temporal patterns of burning across Canada and Alaska. Geophysical Research Letters 33:1-5.

Footnote 159

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Caccianiga, M., Payette, S. and Filion, L. 2008. Biotic disturbance in expanding Subarctic forests along the eastern coast of Hudson Bay. New Phytologist 178:823-834.

Footnote 160

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Forest Managment Branch. 2010 Forest health report. Government of Yukon, Energy, Mines and Resources.

Footnote 161

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Ferron, J. and St-Laurent, M.-H. 2008. Forest-fire regime: the missing link to understand snowshoe hare population fluctuations? In Lagomorph biology: evolution, ecology, and conservation. Edited by Alves, P.C., Ferrand, N. and Hacklander, K. Springer-Verlag. Berlin and Heidelberg, Germany. pp. 141-152.

Footnote 162

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Bryant, J.P., Clausen, T.P., Swihart, R.K., Landhäusser, S.M., Stevens, M.T., Hawkins, C.D.B., Carrière, S., Kirilenko, A.P., Veitch, A.M., Popko, R.A., Cleland, D.T., Williams, J.H., Jakubas, W.J., Carlson, M.R., Bodony, K.L., Cebrian, M., Paragi, T.F., Picone, P.M., Moore, J.E., Packee, E.C. and Malone, T. Fire drives transcontinental variation in tree birch defense against browsing by snowshoe hares. American Naturalist 174:13-23.

Footnote 163

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Ims, R.A., Henden, J.A. and Killengreen, S.T. 2008. Collapsing population cycles. Trends in Ecology & Evolution 23:79-86.

Footnote 164

Return to footnote 164

Blancher, P. and Wells, J. 2005. The boreal forest region: North America's bird nursery. Canadian Boreal Initiative and Boreal Songbird Initiative. Ottawa, ON and Seattle, WA. 9 p. + appendix.

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Theme: Science/policy Interface

Biodiversity monitoring, research, information management, and reporting

Key finding 21
Theme: Science/policy interface

National key finding
Long-term, standardized, spatially complete, and readily accessible monitoring information, complemented by ecosystem research, provides the most useful findings for policy-relevant assessments of status and trends. The lack of this type of information in many areas has hindered development of this assessment.

Because the Taiga Shield ecozone+ is so lightly populated, there is little road access to much of the landscape, making research and monitoring difficult and expensive. Few ecological monitoring programs are designed for ecozones+ with limited access and a small population from which to draw volunteers. The consequence is a shortage of data about most aspects of the Taiga Shield ecosystems, from streamflow to animal populations. Understanding how ecosystems react to change – for example, under what circumstances accumulated changes trigger rapid (catastrophic) change or a gradual transition to a new stateFootnote 167 – is lacking. A problem for ecozones+ such as the Taiga Shield is how to recognize thresholds, given the lack of information available about the ecosystems themselves.

The Taiga Shield ecozone+ is characterized by a relatively large proportion of species at the edge of their ranges, whose abundances cycle, and/or are migratory. Predicting population trends within the Taiga Shield requires understanding the factors that limit the distribution of species. Both peripheral and migratory populations are vulnerable to environmental changes in the parts of their range that lie outside the Taiga Shield, so research both within and beyond the ecozone+ is vital for detecting and explaining trends.

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Specific strengths and gaps in information that emerged in the preparation of this report

Monitoring and research strengths include studies that aid in understanding the ecology of Canada's remaining large migratory caribou populations, for example for the George River herd in the eastern Taiga Shield and the Bathurst herd in the western Taiga Shield (see the Northern caribou population trends in Canada thematic technical reportFootnote 12). Research that links impacts from climate change, development activity, and increased human presence in the Taiga Shield, along with monitoring of herd abundance, distribution, and caribou health and body condition, are needed on an ongoing basis.

Existing information on the Taiga Shield ecozone+ is scattered over several jurisdictions and academic research groups – there is little ongoing ecological monitoring. Much of the information that is available is in the "grey literature" rather than in the published scientific literature. The disadvantage of this is that interpretations of results are not always adequately scrutinized and records are not always readily accessible, especially in the long term.

Coverage of the ecozone+ by climate stations is poor – the existing coverage does not allow for generalization to regional trends.

Knowledge about forest ecosystem processes is crucial for understanding taiga biodiversity. Critical gaps, especially for the western part of the ecozone+, are forest processes in relation to climate change and fire ecology, including the ecological importance, status and trends of invertebrates, fungi, and other poorly studied species assemblages.

Information is lacking on causes of the decline of eelgrass and continued trend monitoring is needed. (The issue of the condition of eelgrass beds in James Bay was referred to the Standing Committee on Fisheries and Oceans which, in 2008, presented a report to the House of Commons recommending in-depth research into the effects of environmental change on the eelgrass beds, as well as larger scale monitoring in James and Hudson bays.Footnote 43)

Information about population cycles, natural disturbances and human impacts comes from time lines too short to provide good insights. Gathering historical information from early records, landscape and proxy studies would provide a broader perspective on trends.

Understanding of ecological thresholds and causes of rapid change in the boreal forest is poor. Thresholds related to weather conditions – for example, for species range extensions, wildlife disease and forest insect outbreaks – are particularly important to understand in order to foresee and detect early signs of major ecological impacts from climate change in the Taiga Shield ecozone+.

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Rapid change and thresholds

Key finding 22
Theme: Science/policy interface

National key finding
Growing understanding of rapid and unexpected changes, interactions, and thresholds, especially in relation to climate change, points to a need for policy that responds and adapts quickly to signals of environmental change in order to avert major and irreversible biodiversity losses.

There are two clear instances of abrupt change for this ecozone+:

  1. the precipitous decline in at least one population of migratory tundra caribou in the past few years (see Migratory tundra caribou on page 47 and Changes in availability of traditional/country foods on page 42).
  2. the rapid breakdown of permafrost in peatlands of the eastern Taiga Shield (see Permafrost trends on page 17).

Compounded disturbances that occur could push communities past their ability to recover.Footnote 168 For example, boreal forests may be resilient to climate trends until the interaction of human-induced changes such as the introduction of non-native species, diseases, or changes in fire regimes combine with atmospheric deposition of nitrogen or heavy metals.Footnote 169

In addition, species diversity is low in the Taiga Shield. A relatively few species drive ecosystem functioning. The low species diversity, combined with cyclic abundance of some species, suggest that changes to ecosystem structure could be large-scale and relatively unpredictable.

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Footnotes

Footnote 12

Gunn, A., Russell, D. and Eamer, J. 2011. Northern caribou population trends in Canada. Canadian Biodiversity: Ecosystem Status and Trends 2010, Technical Thematic Report No. 10. Canadian Councils of Resource Ministers. Ottawa, ON. iv + 71 p.

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Footnote 43

Standing Committee on Fisheries and Oceans. 2008. Fifth report of the Standing Committee on Fisheries and Oceans to the House of Commons. Government of Canada. Ottawa, ON. 2 p.

Return to footnote 43

Footnote 167

Scheffer, M. and Carpenter, S.R. 2003. Catastrophic regime shifts in ecosystems: linking theory to observation. Trends in Ecology & Evolution 18:648-656.

Return to footnote 167

Footnote 168

Paine, R.T., Tegner, M.J. and Johnson, E.A. 1998. Compounded perturbations yield ecological surprises. Ecosystems 1:535-545.

Return to footnote 168

Footnote 169

Chapin, F.S., Callaghan, Y., Bergeron, M., Johnstone, J.F., Juday, G. and Zimov, S.A. 2004. Global change and the boreal forest: thresholds, shifting states or gradual change? Ambio 33:361-365.

Return to footnote 169

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Conclusion: Human Well-being and Biodiversity

Much of the Taiga Shield ecozone+ is intact wilderness, a vast expanse of boreal forest thinning to tundra on its northern margin. Split in two by Hudson Bay, it crosses several political boundaries and encompasses part or all of the traditional territories of the Inuit, and a number of First Nations. The biological resources of the Taiga Shield were once the sole support of its human inhabitants.

Today, they are still important to residents, particularly to Aboriginal peoples. The Taiga Shield’s biodiversity supports the region’s non-cash economy, providing physical essentials such as food, clothing, and fuel. It also serves as a cultural foundation for peoples that have lived in the area for millennia. The growing number of parks and protected areas in the ecozone+ offers some opportunities for future development of the cash economy through tourism and associated services.

The Taiga Shield is also important to people outside the ecozone+. It is the southern edge of the range of the great migratory caribou herds that still sustain many peoples and communities further north. It is also the northern edge of moose habitat, supporting a species important to both people and ecosystems further south. In addition, the Taiga Shield sustains a wide range of migratory birds through part of their yearly cycle, offering a relatively undisturbed respite to species that might be under pressure elsewhere in their range.

The greatest threats to the biodiversity of the Taiga Shield ecozone+ come from human activity, both locally and on a global scale. The physical resources of the Taiga Shield--mainly hydroelectric capacity and mineral resources--have attracted development, with more planned for the near future. Hydro development in the eastern Taiga Shield has flooded large tracts of land and substantially altered the hydrological regimes of several major river systems, with consequences for both terrestrial and aquatic biodiversity. Mineral resource development--particularly in the western Taiga Shield--is still largely in the exploration phase, but a major discovery could lead to a rapid increase in linear disturbance for transportation and communication corridors, resulting in increasing fragmentation of the Taiga Shield’s great stretch of boreal forest.

The other major threat to biodiversity in the Taiga Shield is global climate change. Already, the ecozone+ is showing the effects of warming, and it is vulnerable to stronger impacts as the trend increases. The cumulative impact of climate change and local human activities can be particularly powerful. For example, in the eastern part of the ecozone+, extensive areas of permafrost have decayed, along with the growth of thermokarst ponds.

Maintaining the biodiversity of the Taiga Shield and the undisturbed character of its wilderness is valuable to people within and beyond the boundaries of the ecozone+. It is part of the complex natural mechanism of the boreal forest, one of Earth’s major ecosystems and a significant--if not wholly understood--component of global physical and biological systems.

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