Are we doomed to a perfect storm of extinction? A new report says Canada is ripe for the loss of iconic northern species Mar. 26, 2006. 01:00 AM RICK SMITH SPECIAL TO THE STAR

What do the polar bear, Sumatran tiger, caribou and wolverine all have in common? They are living within "latent extinction risk regions," according to a study published last week in the Proceedings of the National Academy of Sciences.

These are regions where mammals have "a particularly high potential" of going extinct if current trends continue. From a global perspective, they are largely concentrated in the northern parts of North America and the islands of the Bay of Bengal and southwest Pacific.

According to the research team, led by Dr. Marcel Cardillo from the Division of Biology, Imperial College London, these regions have not yet been the subject of efforts to protect endangered species because, so far, they are relatively undisturbed by human activity.

However, this far-sighted study has identified likely scenarios where apparently healthy animal populations will be at risk.

Canadians should note that most of the priority areas identified in the Western Hemisphere lie in this country, concentrated in the far north (boreal forest and tundra) and in the eastern Canadian forests. These areas are so vast and wild that most of us think we don't need to worry about extinction there.

Think again.

First, Canada's eastern forests and northern regions are already home to several species at risk, as well as many more whose biology makes them especially susceptible to population decline. Second, humankind has already helped drive common and widespread species, such as the late regretted passenger pigeon, to extinction.

The last passenger pigeon died at the Cincinnati Zoo just over 90 years ago. Martha, as she was called, was the sole survivor of an avian lineage that was once so prolific that it may have been the most successful species on the planet, in terms of sheer numbers.

The passenger pigeon — a graceful long-tailed species native to North America, not to be confused with the stocky everyday domestic city pigeon of European origin — was counted in the billions, a scale hard to imagine today.

According to naturalist John James Audubon, when a flock of passenger pigeons passed overhead, it would block out the sun, just like an eclipse.

The passenger pigeon was once so common that the Indian word behind the Toronto neighbourhood of Mimico means the "place of the wild pigeons."

Given the birds' abundance in the 19th century, hunters were invited to a "Grand Pigeon Shooting Match" at the Golden Lion Inn on Toronto's Yonge St., back when the corner of Yonge and Sheppard had a landscape suitable for a country inn. Shortly thereafter, the passenger pigeon was wiped out by a human-induced Murphy's Law scenario. It went from super-abundant to extinct in the blink of an eye.

Everything that could go wrong did, as several factors aligned to extinguish the passenger pigeon. Its tendency to group together in huge flocks made it easy to find and kill, thousands at a time. Its attractiveness as a food source and sport hunter's target coincided with the widespread availability of guns. And its preferred forest habitats were being cut down.

While it might have withstood the effects of any one of these factors in isolation, in combination they proved to be deadly.

But the passenger pigeon became extinct nearly a century ago. Haven't we learned our lesson? In part. The destruction of species by hunters is no longer the number one threat to wildlife. And in some cases we have established regulations that have made a difference to species such as beaver, marten, fishers and otters. These once-abundant species were seriously depleted throughout large parts of their ranges in the early 20th century as a result of the fur trade. Their numbers have now rebounded, in a relatively short period of time, thanks to limits on fur harvesting.

But the primary threat to species today is loss of habitat. Simply put, without a home, species do not survive. Hunting quotas or catch limits are of little use if a species is losing the habitat that it needs for survival. This particular problem, according to Cardillo and his colleagues, requires pre- emptive conservation planning.

The polar bears, caribou and wolverines at risk today are the mammal equivalents of the passenger pigeon, whose life history was such that it could not recover once it started on the steep slope of population decline. The lessons to be learned from both the history books and leading-edge science have something in common.

The Cardillo study is based on species biology; specifically, that those with a large body mass and slow reproductive rate are highly sensitive to disturbance. This is the case for caribou, wolverines, polar bears and other icons of the Canadian wilderness.

Caribou, our North American reindeer, inhabit both the tundra and the forest. In Ontario, woodland caribou have suffered dramatic declines in their historic range over the last 150 years. Once ranging as far south as Algonquin Park, they have disappeared from about 40 per cent of their former range as a result of industrial development.

The historical records on wolverine are not as detailed as those of caribou but nevertheless indicate a comparable range decline. The stronghold of the wolverine in Ontario once stretched as far south as Lake Nipissing, near North Bay, with individual animals venturing even further south. Now that stronghold lies north of Lake Nipigon — beyond the current limits of industrial forestry operations.

The habitat requirements of polar bears make them vulnerable to a threat of a different kind. Even if their present habitat were to remain untarnished by industrial exploitation, global climate change threatens the sea ice on which they depend for survival.

Cardillo's research team characterizes the "latent extinction risk" concept as a "proactive extension" of the usual remedial approach to species protection. This remedial approach focuses on minimizing biodiversity loss in areas that have already been severely disturbed by human activity. What is needed in addition are measures to prevent species from ever becoming endangered in the first place.

Today, it's hard to picture what it was like in the forests of southern Ontario when elk, cougar and bears roamed freely. But it's equally hard to picture our northern forests without bears, wolverines and caribou. The Cardillo study reminds us that history is doomed to repeat itself unless we take concrete steps now.

In Ontario, one source of hope is the government's commitment to update Ontario's ineffective Endangered Species Act. Critical to the new act's success will be recognition that prevention is the best medicine.

Murphy's Law should not apply to our dealings with endangered plants and animals. Rather, we need to enact effective legislation — we could call it Martha's Law, after the last of the passenger pigeons.

By passing and implementing such a law, the Ontario government can ensure that future generations will enjoy learning about Ontario's natural wonders first-hand rather than just in history class. Rick Smith is executive director of Environmental Defence. This piece was co-written with Wendy Francis (Ontario Nature), Janet Sumner (CPAWS-Wildlands League) and Robert Wright (Sierra Legal Defence Fund), all members of Save Ontario's Species (http://www.saveontariospecies.ca).