BIODIVERSITY - A Canadian Perspective
Northern Spotted Owl Photo credit: Sharon Toochin
Northern Spotted Owl
In Canada, the Northern spotted owl is found only in the southwestern corner of British Columbia. This handsome medium sized owl, with its dark-brown eyes, relies on old-growth forests to roost, nest and forage. Due to ongoing logging of the ancient forests in southwestern British Columbia, scientists estimate that just 33 potential breeding pairs now remain. The historic population of spotted owls in Canada is estimated to have been 500 pairs.
Government scientists predict that the spotted owl will be extinct in Canada within a decade unless immediate action is taken to stop logging in their old-growth habitat (22).
Polar bear moom and cub Photo credit: Art Wolfe
Polar Bears
This majestic animal used to be perfectly adapted to survive the extremely cold temperatures and desolate conditions of the arctic, however, due to climate change the arctic is warming rapidly and the polar bear can’t adapt quickly enough. Climate change is specifically affecting the way polar bears feed. Polar bears normally come ashore in the late spring when the sea ice breaks up, making them unable to use floating ice to hunt ringed seals, their primary food source. Once on land, most polar bears fast waiting for the cooler weather to form pack ice, so that they can return to their hunting areas.
Lately, as the Arctic becomes warmer, the pack ice returns later and later each year and recedes earlier. The result is that the bears spend less on the ice and therefore forced to fast for longer periods. In Churchill, this disturbing phenomenon has resulted in the local polar bear population becoming thinner and less healthy, with fewer cubs being born each year (23).
Beluga Whales
- St. Lawrence sub-species -Our marine environment has become increasingly polluted, taking a deadly toll on animals living in contaminated waters. One example is the small, endangered population of beluga whales in the St. Lawrence Estuary. This population of ghostly white whales is slowly being poisoned by high levels of toxic contaminants (such as PCBs, DDT and heavy metals) in its estuary habitat, due to industrial and agricultural run-off (24).
Prothonotary warbler Photo credit: Robert Lankinen
Songbirds
Conservationists have been wondering what has happened to songbirds that once summered so plentifully in the boreal forests of northern Canada. Over the last several decades, numerous species of songbirds have declined sharply including the hooded, Canada and Cape May warbler, white-throated sparrow and Philadelphia vireo. Although the reasons for the decline are not fully understood, scientists believe that loss of wintering tropical rainforests combined with the ongoing loss and fragmentation of Canadian forests and aspen parkland are major limiting factors for songbirds.
New research has shown that the boreal forest is the breeding grounds of up to five billion land birds each year, and one in every three of North America’s songbirds is born in Canada’s northern boreal forest (25).
Ponderosa Pine Photo credit: Adrian Dorst
Amphibians
Research shows that amphibians, such as Canada’s Rocky Mountain tailed frog, have been in decline globally for the last half-century, with a startling decline in the 1960s and a steady decline since - averaging 5% annually. Scientists fear that local climate changes, habitat loss, acid rain, disease and increased solar radiation are responsible. Amphibians have been heralded as important environmental indicators, as most species have aquatic and terrestrial life stages that reflect changes in both environments. Very sensitive to the health of their habitat, amphibians can provide early warnings of serious environmental problems (26).
Western skink Photo credit: Jakob Dulisse
Endangered Ecosystems
The four most critically endangered ecosystems in Canada are the Carolinian woodlands of Ontario, tall-grass prairie of Manitoba, the South Okanagan grasslands and the Garry Oak ecosystem on Vancouver Island. Not surprisingly, many species in these fragmented fragile ecosystems are also endangered.
Woodland Caribou Photo credit: Terry Parker
Carolinian Forests
The Carolinian forest zone in southern Ontario, which serves as a bridge between the boreal, aspen parkland and US Appalachian forests, has an amazing diversity of both plant and wildlife species. Biologists estimate that 2,200 species of herbaceous plants are found here, including 70 species of trees. Although this forest comprises just a fraction of the total land base of Canada, it is currently the home for one quarter of our nation’s total human population. Development pressure has had a huge impact on this landscape, and in under a century more than 80% of its forest cover has been lost. Today the Carolinian forest is now in the unfortunate position of hosting more endangered and rare species, including the Acadian flycatcher, Southern flying squirrel, Blanchard’s cricket frog and the Eastern prickly pear cactus, than any other area in Canada (27).
Prickly Pear Photo credit: Robert McCraw
Plant Communities
Often overlooked, plants make up over one third of Canada’s species at risk. American ginseng, showy goldenrod, pitcher’s thistle and drooping trillium are just some of the rare and endangered plants found throughout Canada.
Less charismatic than a grizzly bear, beluga whale or Northern spotted owl, plants often disappear with no one chronicling their absence. When plants become extinct we are losing what has often not even been identified. When plants vanish from ecosystems we lose genetic diversity, undiscovered medicinal properties and ecological integrity as when plants become extinct as many as 30 other species that have adapted to that plant may also decline.
Humpback whale Photo credit: Art Wolfe
South Okanagan
The South Okanagan - Similkameen Valley makes up just over one percent of the landbase of BC, yet it home to 30% of British Columbia’s endangered species. The valley accommodates a combination of coniferous forests, desert-like grasslands, wetlands, and rocky bluffs, making this one of the most productive ecosystems in the country.
Nearly half the bird species in the country can be found here, along with many plants and animals, such as the endangered night snake, that are found nowhere else in Canada.
Unfortunately, this extraordinary area has been turned into one of the most endangered regions in Canada due to rapid urbanization and agricultural development (28).
Ocean Species
- A tragedy of the commons -The “efficiency” of industrial fishing fleets combined with wholly inadequate government safeguards has resulted in a crash of commercial fish stocks worldwide. In just a few short decades of industrial fishing, the world’s oceans have lost 90% of predatory fish, such as tuna, blue marlin and swordfish.
This tragedy of the commons is familiar to most Canadians who saw how the collapse of the cod fishery in Atlantic Canada decimated not only an entire ecosystem but also the small fishing communities that relied upon this once plentiful resource.
If over fishing continues, the world can expect serious economic disruptions, mass extinctions of sea life, food shortages in many developing nations and lasting damage to marine ecosystems (13).
Species at Risk in Canada Click on map to enlarge. Map credit: EcoMap data, Natural Resource Canada 1998
