Invasive non-native species

Trends in non-native species in the Great Lakes

Graphic thumbnail: trends in non-native species in the Great Lakes

This bar chart shows the cumulative number of non-native species in the Great Lakes, categorized by ranges of years. The data are presented in the following set of points:

  1. prior to 1849, 9 non-native species were present;
  2. by 1899, 43 were present;
  3. by 1949, 86 were present;
  4. by 1999, 173 were present; and
  5. by 2008, 185 were present.

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Native mussel declines

Graphic thumbnail: native mussel declines

This map of Lake Erie, Lake St. Clair, the Detroit River, and the Niagara River shows sites that have data on the numbers of freshwater mussel species before and after zebra mussel invasion. The data, displayed on a bar graph, show steeply declining numbers of native mussels species at all sites where samples were taken pre and post-invasion. The data are presented in the following set of points, by site:

  1. Lake St. Clair: the sample site on the eastern shore of the lake had 5 species post-invasion. No sample was taken pre-invasion. A site along the southern shore of the lake had 11 species pre-invasion and 0 post-invasion. A site in the middle of the lake had 19 species pre-invasion and 5 post-invasion;
  2. the Bass Islands in southwest Lake Erie had over 20 species pre-invasion and 0 post-invasion;
  3. Rondeau Bay on the northwest shore of Lake Erie had 10 species pre-invasion, and approximately 1 post-invasion;
  4. Presque Isle Bay on the southeast shore of Lake Erie had approximately 15 species pre-invasion and 0 post-invasion;
  5. Port Maitland on the northeast shore of Lake Erie had approximately 15 species pre-invasion and approximately 5 post-invasion; and
  6. the Niagara River had fewer than 5 species post-invasion, with no samples taken pre-invasion.

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Distribution of birds testing positive for West Nile virus

Graphic thumbnail: distribution of birds testing positive for West Nile virus

This map of Canada with ecozone+ boundaries shows the locations of birds found from 2001 to 2003 that tested positive for West Nile virus. The highest concentration of positive birds was in the Mixedwood Plains Ecozone+, spanning southern Ontario and Quebec and east to the Atlantic Maritime Ecozone+. Positive birds were also found sporadically in New Brunswick and Nova Scotia and in the southern portion of the Boreal Shield Ecozone+. A high number of positive birds were also found dispersed across the Prairies Ecozone+ and along the southern border of the Boreal Plains Ecozone+.

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Global spread of chytrid fungus of amphibians

Graphic thumbnail: global spread of chytrid fungus of amphibians

This timeline shows the date of the earliest occurrence of chytrid fungus in major global regions. The fungus first occurred in Africa in 1938, in North America in 1961, in Australia in 1978, in Central America in 1983, in South America in 1986, in Europe in 1997, and in Oceania in 1999.

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Invasive non-native plants

Graphic thumbnail: invasive non-native plants

This line graph displays the cumulative number of invasive non-native plant species in Canada. From 1600 to 1800 the number increased, reaching approximately 50 by 1800. From 1800 to 1905 the number of new species increased at a more rapid rate, reaching over 200 by 1905. Over the next century the rate of increase was more moderate, reaching 245 in 2005.

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Expansion of the European common reed

Graphic thumbnail: expansion of the European common reed

Three maps show the extent of the European common reed in 1980, 1995, and 2002, along the St. Lawrence River in Quebec. In 1980 European common reeds were found only in the river channel. By 1995 the distribution had expanded within the channel as well as on to land; by 2002 all locations that were already colonized by the reed had expanded in size.

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St. Lawrence River, Quebec

Graphic thumbnail: St. Lawrence River, Quebec

This map of Canada shows the location of the St. Lawrence River, Quebec.

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