Montreal

Rapid rates of global warming will be bad news for biodiversity, particularly in the far north, according to a report prepared for the World Wildlife Fund and released recently in Toronto.

Changing homes: tundra-living species such as these caribou are threatened by climate change. Credit: GALEN ROWELL/CORBIS

Jay Malcolm, of the University of Toronto's forestry faculty, and Adam Markham, of the non-governmental organization Clean Air–Cool Planet, based in Portsmouth, New Hampshire, warn that many species may be unable to migrate “away from increasingly less favourable climatic conditions to new areas that meet their physical, biological, and climatic needs”.

The researchers used seven climate models and two vegetation models to analyse how fast species might have to move to keep up with projected warming.

High migration rates will be required over 38.3% of the land surface of Russia and 33.1% of Canada. The authors conclude that species living in the tundra and in coniferous forests “may be among the most vulnerable to global change”.

In many countries, including Sweden, Finland and Iceland and several former Soviet republics, more than half of the existing habitat could be lost or changed into another habitat type. The same goes for seven of the twelve Canadian provinces. And in the United States, more than a third of existing habitat in eleven states could change.

Noting that even relatively optimistic predictions suggest that carbon dioxide concentrations are likely to have doubled by around the middle of this century and almost tripled by 2100, the researchers suggest that species may need to move even faster than their findings indicate.

“If past fastest rates of migration are a good proxy for what can be attained in a warming world, then radical reductions in greenhouse gas emissions are urgently required in order to reduce the threat of biodiversity loss,” the authors conclude.