March 24, 2006

When most of us think about protecting species, we tend to envision ways of saving those creatures that are most endangered or whose populations are perilously low. This makes perfect sense - a kind of species triage, if you will. But it's also the most expensive and least effective way to prevent species from disappearing.

Far more effective would be to first identify which species may be doing fine currently, but are likely to be in trouble in the near future. This would enable us to create more cost-effective conservation plans that will keep populations at healthy levels, rather than just on life support. But how do you identify those species on the edge?

A new report recently published in the Proceedings of the National Academy of Sciences does just that. Researchers looked at available databases for information on nearly 4,000 non-marine mammal species, then mapped the global geographic distribution of what they call "latent extinction risk." The results were surprising.

It turns out that the areas with the highest latent extinction risk are often not those that currently have a high number of endangered species - so they aren't often singled out for conservation. Most species conservation measures currently tend to focus on what have been called biodiversity "hotspots" - areas, usually in the tropics, which have very high levels of life diversity. However, this new research highlights a kind of "latent hotspot" where the potential for future loss of species is very high. And two of the largest areas in the world are in Canada.

Why Canada? Well, different species respond in different ways to human encroachment. Some can tolerate greater human disturbances than can others. Those that don't tolerate human impacts very well, such as road-building, hunting, oil drilling and logging, are more likely to suffer once people begin to move into their habitats. These creatures tend to be confined to relatively small geographic areas, have a large body mass or are slow to reproduce.

It turns out that the boreal forest of northern Canada and the eastern forests of Ontario, Quebec and the Maritimes have lots of species with some of these characteristics - ungulates such as musk oxen and caribou, for example, or large carnivores such as polar bears or lynx. Some populations of these species have been fairly sheltered from human activity because of Canada's vast size, challenging weather and geography. However, as human activities encroach on their habitat, they are at risk of serious and sudden decline.

This precipitous drop is called "leapfrogging," where a species previously considered robust suddenly passes other endangered animals and declines to the point of near extinction. It happened between 2000 and 2004 with the Guatemalan howler monkey when its critical forest habitat was destroyed.

In total, researchers for the Proceedings of the National Academy of Sciences paper identified 20 hotspots of latent extinction. Many of these areas are islands, such as New Guinea, Sumatra, and Borneo in Indonesia, the Bahamas and the Melanesian Islands, where geography severely limits species ability with withstand human pressure.

Canada may have two of the largest areas of concern for latent extinction risk, but we are lucky in that we have a small population and a large land base. We have the resources and the time to develop conservation plans that that this new research into account.

A latent hotspot analysis cannot help bring back the myriad species that are already endangered but, critically, it can help us prevent species from becoming endangered in the first place. It offers policy makers new, potentially less costly and more effective options to protect biodiversity. And that's an opportunity that we'd be foolish to ignore.