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Key findings at a glance: national and Ecozone+ level

Table 1 presents the national key findings from Canadian Biodiversity: Ecosystem Status and Trends 20103 together with a summary of the corresponding trends in the Mixedwood Plains Ecozone+. Topic numbers refer to the national key findings in Canadian Biodiversity: Ecosystem Status and Trends 2010. 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. For many topics, additional supporting information for the Ontario portion of the ecozone+ can be found in the Mixedwood Plains Ecozone+ Status and Trends Assessment – with an emphasis on Ontario.4 See Preface.

Table 2. Key findings overview.
Themes and topicsKey findings: NationalKey findings: Mixedwood Plains
1. ForestsAt 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.Forests cover approximately 25% of the Mixedwood Plains Ecozone.+ Whether forest cover has increased or decreased depends on the location within the ecozone+. Between 1959 and 1995, forest cover increased by 3.3% per decade in the Frontenac Arch and by 2.9% per decade in the Quebec portion of the ecozone+ between 1969 and 1995. However, forest continues to be lost near urban areas. When compared to the forest found in the ecozone+ during the 19th century, current forests have younger old growth, less conifers, and more early successional species.
2. GrasslandsNative 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.Less than 3% of the prairie and savannah originally found in the ecozone+ remains. Though the extent of alvar in Manitoulin Island and the upper Bruce Peninsula has decreased, there may have been increases in alvar in the Carden Plain. Both prairies and alvars are home to numerous species at risk.
3. WetlandsHigh 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.

Only 28% of the total wetland area originally found in the Ontario portion of the ecozone+ remained in 2002 (72% loss). Between 1982 and 2002, wetland loss averaged 0.17% per year. Most of the Ontario portion of the ecozone+ has less than 50% of its remaining wetlands in patches over    200 ha in size. Swamp is the most common wetland type.
The freshwater tidal marshes found along the St. Lawrence River are the largest and some of the least polluted in North America and a very rare habitat worldwide. The Great Lakes coastal wetlands provide continentally significant habitat for many migratory waterfowl.

Restoration efforts and reduced water levels in the Montréal and Lac Saint-Pierre areas have resulted in a 2.7% net gain in marshes and swamps between 1990 and 2002.

4. Lakes 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.Water temperatures have increased over the last 30 to 40 years. Water levels and flows have been greatly altered by the construction of canals and dams. The ecozone+ has the highest freshwater fish biodiversity in Canada (78% of the species found Canada). Of the 131 species native to the ecozone+, 36 are of conservation concern, more species than any other vertebrate group in the ecozone+. The distributions of cold-water species have contracted the distributions of warm-water species have expanded.
5. CoastalCoastal 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.Tidal marshes are discussed under the wetlands key finding.
6. MarineObserved 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.Not relevant for the Mixedwood Plains Ecozone+.
7. Ice across biomessDeclining 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. A trend towards earlier break-up and longer ice free season has been observed for the ecozone+ (1853–2001). On average, in the years between 1975 and 2004, freeze-up of the Great lakes has been occurring 3.3 days later per decade with an average decrease in ice duration of 5.3 days per decade, compared with historical rates. Fish species such as lake whitefish and lake trout which require cold water temperatures for successful spawning have poorer larval survival with warmer water temperatures (associated with less ice cover).  Warmer water temperatures also create thinner near-shore ice which is easily broken up by wind resulting in ice piling and loss of invertebrate habitat. Increases in “lake effect snow” are also associated with years with lower ice cover on the Great Lakes.
Dunes Note a of Table 2Dunes are a unique biome with a very limited distribution in Canada. As a result, information on dunes was not identified as a nationally recurring key finding nor was it included in one of the other key findings in the national report.Because of their significance to biodiversity in the Mixedwood Plains Ecozone+, information on dunes is included as a separate ecozone+-specific key finding in this report. The fragile ecosystems of coastal dunes can be easily disturbed by both human and natural forces. Lower lake levels and reduced groundwater supplies, resulting from predicted climate change, may have negative impacts on dune ecosystems, and development pressure is expected to continue along the Great Lakes shorelines, where dunes are predominately located in this ecozone+.
8. Protected 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.The Mixedwood Plains Ecozone+ is predominately private land with few government lands available for protection. Growth in traditionally designated protected areas has thus been very difficult. Prior to 1992, 0.7% of the ecozone+ was protected in these types of regulated protected areas. By May 2009, this had increased to 1.6%, covering 1,887 km2.
The majority of natural heritage protection occurs on private lands through a number of designations and mechanisms with varying degrees of protection.
9. StewardshipStewardship 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.With a high proportion of the Mixedwood Plains in private ownership, voluntary stewardship activities are a crucial component of biodiversity conservation.  Stewardship includes protection activities such as easements and land securement, incentive programs, restoration activities such as planting trees, and education and awareness activities such as nature interpretation centres and programs for youth.  Overall, stewardship in the Ontario portion of the ecozone+ has two long term trends: increasing levels of public engagement; and increasing scale of stewardship activities. Despite this there is little coordination between the parties doing stewardship and no monitoring to determine if the actions are adequate to help ensure a healthy and functioning ecosystem.
Ecosystem conversionNote b of Table 2Conversion of one land use or land cover type to another is poorly documented in Canada. Estimates available show an increase in some land uses, for example urban area (~ 15,200 km2) and hydro reservoirs (~27,000 km2), and a decrease in agricultural land (~ 18,500 km2) over the past 30 to 40 years. These changes translate into loss of natural habitat and agricultural ecosystems. (under review)The Mixedwood Plains has undergone some of the most extensive changes in land cover of any ecozone+ in Canada (second only to the Prairies). In 2011, it was comprised of 68% agricultural land and contained 53% of Canada’s population. In the Ontario portion of the ecozone+ between 1951 and 2006, the sparsely populated and rural lands declined to 58% of the 1951 level while the land area with urban population densities almost tripled.  The steepest growth was in the semi-urban category.  The increases in urban area came at the expense of farmland and, to a lesser extent, forest cover.  Agricultural intensification has occurred as pasturelands and hayfields have been reduced and cropland area increased.
10. Invasive 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.The Mixedwood Plains has the greatest number of invasive non-native plant species (139 in 2008) of any ecozone+in Canada due to the long settlement history and role as a port of entry for goods from around the world. Despite the ongoing influx of invasives, a few control measures, such as those taken against purple loosestrife, have begun to show positive results.
11. ContaminantsConcentrations 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.The concentrations of legacy contaminants such as DDT, lead, and mercury have been reduced but still persist in the environment. Emerging contaminants such as PBDEs, PCNs, and PFCs are starting to be monitored but data is limited. Concentrations of mercury continue to be a concern and are the cause of more than 85% of fish consumption restrictions in the Ontario portion of the ecozone+.
12. Nutrient 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.In general phosphorus levels have declined since the 1980s, however many rivers and streams in the Ontario portion of the ecozone+ continue to exceed the interim Provincial Water Quality Objective of 30 ug/L of phosphorus in areas where soils are relatively rich and the land has been developed for agricultural and urban use. Between 1994 and 2009 there was a significant increase in the number of reports of cyanobacteria (blue-green algae) blooms in the ecozone+.
13. Acid 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.Due to the underlying geology of the Mixedwood Plains most lakes are well-buffered against the impacts of acidification. Concerns about acidification are focused on the Frontenac Arch, which has soils susceptible to acidification and relatively high forest cover.
14. Climate 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.Summer temperatures and fall and spring precipitation have increased in the ecozone. There has been a decrease in the number of growing degree days, and decreases in snow depth. Broad scale ecolological impacts are projected based on continued warming related to changes in northward expansions of species, changes in timing of bird migration, and increases in plant pests and diseases.
15. Ecosystem 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.A recent conservative estimate of the economic value of the ecosystem goods and services provided by the Ontario portion of the ecozone+ is $84 billion per year.
Intact landscapes and waterscapest Note c of Table 2Large tracts of relatively intact natural landscapes and waterscapes, where ecosystem processes are either known or presumed to be functioning properly, are found in many areas, but particularly in the north and west. This includes globally and nationally significant terrestrial, freshwater and marine movement corridors. (under review)The Ontario portion of the Mixedwood Plains is highly fragmented with a low of 18% natural vegetation in the Southwest and a high of 57% in the Frontenac Arch. Large patches (greater than 200 ha) make up 41% of the Niagara Escarpment and only 5% of the Southwest. In the Ontario portion of the ecozone+, the area with the most roads is the central physiographic zone in Ontario with 1.89 km of roads/km2. The lowest density of roads in Ontario portion of the ecozone+ is found in the Frontenac Arch with 1.14 km of roads/km2. Dams, weirs, and other barriers to aquatic systems are frequent in the ecozone+.
16. Agricultural 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.The wildlife habitat capacity index of agricultural lands in the ecozone+ declined between 1985 and 2006.This is due to a 37.6% decrease in pasture and a 4.8% decrease in natural cover on farm properties and an increase in the area of cropland. The lowest wildlife capacity on farmland is found in the Lake Erie lowland in southwestern Ontario.
17. Species 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.As of 2009, there were 865 species of conservation concern in the ecozone+. In 2005, between 65 and 70% of freshwater mussels and reptile species fell into categories of conservation concern. Serious declines have also been found in birds of open agricultural habitats, grassland birds, colonial waterbirds, shorebirds, and even some birds of urban areas.  This ecozone+ has 97% of the freshwater fish species found in Ontario and 86% of the total for Quebec and 78% of the species for Canada.  Significant declines are being seen in bumblebee species. All of the 12 species of reptiles and amphibians found only in the Mixedwood Plains are at risk. Turtles appear to be in the greatest peril as seven of the eight native species (87.5%) are at risk. Snakes are similarly imperilled, with 11 of 17 (65%) of the species listed as at risk.11
18. Primary 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.The forested portions of the ecozone+ have some of the highest net primary productivity (NPP) reported in Canada though the average NPP for the ecozone+ as a whole is moderate.  Primary productivity has been increasing across the ecozone+ at 2 g C/m2/yr, potentially due to increases in precipitation.
19. Natural 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.Historically, wind is thought to have been a larger disturbance than fire in this ecozone+. The ecozone+currently does not have a natural fire regime due to fire suppression activities. Historically, frequent surface fires which supported small-scale gap disturbances would have been the most common fire type in the ecozone+’s forests.  Insects damaged 14.8% of forests in the Ontario portion of the ecozone+ between 2001 and 2005 while 0.05% of forest cover was impacted in Quebec between 1969 and 1995.  Forest tent caterpillar and spruce budworm are the two most common forest pests and are responsible for about half of the damage done to Ontario forests within the ecozone+.  It is difficult to know whether native insect infestations are at levels higher than would have historically occurred.  The area infested by invasive non-native forest insects such as gypsy moth, emerald ash borer, and sirex wood wasps is in excess of natural disturbance levels as these species never occurred naturally within the ecozone+.
20. Food 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.Human activities in the ecozone+ have led to a number of changes in the relationships among species. Large carnivores, though still found in the ecozone+, are restricted to areas with higher levels of natural cover. Species tolerant of human activities (e.g., white-tailed deer, skunks, raccoons) have increased.
21. Biodiversity 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.Most of the Ontario data available for this ecozone+was generated to answer specific research or management questions and was not part of a long-term monitoring program. Generally, long-term, broad-scale monitoring programs which would provide data to support initiatives such as ESTR have not been designed, resourced, or implemented for the Ontario portion of this ecozone+.  At the community level the lack of up-to-date land cover data prevents the tracking of broad-scale landscape change.  At the species level, much of the long-term trend data comes from citizen science and little monitoring is being done overall. With the many jurisdictions involved in environmental monitoring (more than 200), data standards and lack of coordination are two of many issues.
22. Rapid 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.Three diseases found in the ecozone+ typify the problem of rapid change coupled with poor understanding. White-nose syndrome, which often causes mortality rates of more than 75% in hibernating, cave-roosting bats has spread into the ecozone+.  Chytridiomycosis which is considered a significant disease affecting amphibian diversity worldwide has been found to be present in amphibians within the ecozone+. Viral hemorhagic septicaemia was originally considered a disease of freshwater rainbow trout in Europe. It has now been found in 30 species of fish from the Great Lakes and is often associated with significant mortality.

Notes of Table 2

Note a of Table 2

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

Return to note a referrer of table 2

Note b of Table 2

Ecosystem conversion - This key finding is not numbered because status and trend information related to it was incorporated into other key findings in the final national report.3 However, as information was compiled and assessed separately for this finding for this ecozone+, it has been included in this report. 

Return to note b referrer of table 2

Note c of Table 2

Intact landscapes and waterscapes - This topic is not numbered because status and trend information related to it was incorporated into other key findings in the final national report.3 However, as information was compiled and assessed separately for this finding for this ecozone+, it has been included in this report.

Return to note c referrer of table 2

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