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Going Going Gone
Species at Risk
What is a Species at Risk?Any species of plant or animal that is
declining below a certain level
Before commercial whaling est. 50,000
Present Estimated Population 9,000
Eg. Bowhead Whales
How do we classify Species at Risk?• Different levels depending upon seriousness
Vulnerable- a species particularly at risk because of low or declining numbers
Eg. Polar Bears (21,000- 28,000)
How do we classify Species at Risk?• Different levels depending upon seriousness
Threatened -a species likely to become endangered in Canada if the factors affecting its vulnerability are not reversed.
Eg. Wood Buffalo (declining due to infection)
How do we classify Species at Risk?• Different levels depending upon seriousness
Extirpated-a species no longer existing in the wild in an area but occurring elsewhere
Eg. Grizzly bear (Range has been decreased to only BC and Alberta)
How do we classify Species at Risk?• Different levels depending upon seriousness
Extinct - this species has not been found anywhere
Eg. Blue walleye of Lake Erie
Went extinct in the 1960’sbecause of over fishing, water pollution, and the introduction of the invading smelt population
How do we classify Species at Risk?• Different levels depending upon seriousness
Endangered- a species close or thought to be extirpated throughout Canadian range
Causes of Decline
• Usually multiple reasons including. – loss of habitat – Over harvesting – Climate change – Competition from invading species