It’s known that Canada is home to tens of thousands of species of plants and animals, several hundred of which are listed under the federal Species at Risk Act. But what has been harder for biologists to establish is exactly how many of those species are found only in Canada.

Now a new report has provided the most comprehensive list to date of the plant and animal varieties for which Canadians bear sole responsibility.

“These species are a key part of Canada’s role in stopping global extinctions because no other country will decide their fate,” said Dan Kraus, a biologist with Nature Conservancy Canada and a co-author of the report, which was produced jointly with NatureServe Canada, a non-profit organization that supports data gathering for conservation science. The report was released on Thursday.

The product of a two-year effort to comb through digital databases and specimen collections across North America and beyond, the report not only provides an updated list of Canada’s endemic species – plant and animal varieties that are unique to the country – but shows how those species are distributed. Dr. Kraus said the report could help inform decision makers about which wildlife areas should be prioritized for protection, including areas that are deemed vulnerable to climate change.

Canada is working to meet international commitments to biodiversity, including setting aside 17 per cent of land and freshwater areas for protection by the end of 2020. Conservation groups have been seeking to make those allocations count by identifying key areas for protection using common international criteria.

In total, the report identified 27 hot spots as having an especially high concentration of endemic species, including some areas that are not typically seen as priority areas for species at risk.

Even more troubling, only one in 10 of the endemic species in the report are deemed to be secure in terms of their conservation status. Most are considered threatened to some degree, but less than 20 per cent have been assessed as part of the process that would lead to a formal listing as a species at risk.

Joseph Bennett, a biologist at Carleton University who reviewed the report, said that while Canada’s species laws are rightly designed to protect all native species, it is important that species that can only exist in Canada are not overlooked in conservation decisions.

“If we mess up, they’re gone, globally,” he said.

Unlike many countries, particularly in the tropics where biodiversity is highest, Canada has relatively few endemic species. Many species that are considered representative of the country, from beavers to Douglas firs, also range across the United States. Some High Arctic Canadian species also live in Greenland and Siberia.

Included among the 308 plant and animals that are listed in the report as endemic to Canada are some that hold a special place in the country’s history. For example, the hairy braya, a delicate white flower that grows only on the Cape Bathurst Peninsula and Baille Islands of the Northwest Territories, was first described during Sir John Franklin’s second expedition to the Arctic in 1826. Since then, its shoreline habitat has become far more susceptible to erosion due to reduced ice cover and sea-level rise.

A total of 21 mammals are listed in the report. The largest is the wood bison, which became unique to Canada after having been wiped out in the United States (not including an experiment to reintroduce the species in Alaska). Others, such as the eastern wolf and Peary caribou, are subspecies that are genetically distinct because they are geographically separated from other populations of the same species.

Over all, the list underscores the fact that around 10,000 years ago much of the country was blanketed by glaciers. Many of Canada’s native species moved in after the glaciers retreated. But among those species that are unique to Canada are some that predate the glaciers and survived the ice age in areas that were ice free, such as on the island of Haida Gwaii, off the British Columbia coast, or on the outer edges of the maritime provinces.

Other endemics are found in unique landforms that are the inland equivalent of islands, including the Cypress Hills of southern Saskatchewan or the Athabasca sand dunes.

Diana Stralberg an ecologist and research associate at the University of Alberta, said the hot spots reveal the role that small, isolated areas can play in driving the evolution of new species. Ironically, she added, whereas places that were slightly warmer than their surroundings may have helped species survive the ice age, in the future it will likely be places that are somewhat cooler that can serve as refuges for species that are under pressure from climate change.

IVAN SEMENIUK
SCIENCE REPORTER
The Globe and Mail, June 4, 2020