National Post (National Edition)
THE LOON COULD SOON DISAPPEAR FROM LARGE PARTS OF CANADA.
The common loon and its haunting cry could disappear from parts of Canada in two or three decades, as climate change drives the bird farther north, a new analysis suggests.
The National Audubon Society has published an analysis of how the “range” of birds — the map of their summer and winter homes — will shift in a warming climate.
It concludes that “314 species — nearly half of all North American birds — (are) severely threatened by global warming.” Many will have to adapt to new landscapes to live. Bird biologists say migration patterns of many species are already shifting.
Audubon’s scientists believe that loons will be forced north to find conditions similar to where they live today.
The study suggests that loon ranges will change all across Ontario, Quebec, and Atlantic Canada.
Already in 2020, the loon population in Ontario is likely to be thinning compared to 2000, the year chosen as the study’s starting point, it says.
By 2050, the society says it expects to see few or no loons in the region.
And by 2080, the society says they will be even farther away in summer, in the James Bay and Hudson Bay Lowlands, and we may even be on the edge of their winter range. (If so, they will be showing only their dull grey winter feathers, and they wouldn’t be making their eerie call as they have no territory to defend outside breeding season.)
One leading loon scientist cautions that the prediction is based on only two factors — changes in temperature and precipitation, and that reality could be more complex.
“Their projection is likely to provide a crude estimate of the impact of climate change on loons, not a precise one,” says Walter Piper of Chapman University in the United States. He has been studying loons on about 200 small lakes in Wisconsin for 25 years — territory on the edge of the Canadian Shield, very similar to the Ottawa region.
He writes in his research blog, “Loons are likely to cope with climate change better than most other birds — as they have other environmental threats. Then again, loons might be especially sensitive to climate change and retreat northward more rapidly than the study predicts.”
So far, at least, he has not seen a decline in loon numbers, which the Audubon model predicts between 2000 and 2020. Rather, he has seen the reverse.
Loons were badly hurt by DDT in the late 1900s, he notes. “Breeding populations are now generally stable or even increasing across most of the northern tier of (the) United States.
“My study area in northern Wisconsin is typical; loons have recolonized many lakes in the past few decades from which they had retreated. So loon populations are thriving despite extensive shoreline development, entanglements with hooks and fishing line, and increases in methylmercury levels, among many other challenges.”
Loons, then, are survivors. But while they have survived one group of threats, ranging from DDT to human encroachment, the climate is a different type of threat that Piper calls “more extensive and unrelenting than others that loons have faced.”