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