SFU prof links sandpiper wingspan change to return of peregrine falcon
A comprehensive study published this week in the U.S. found climate change could be the reason why the bodies of some migratory birds are shrinking, while their wingspans increase.
The study is notable to Canadian researchers, as the majority of the birds collected, after they died from colliding with buildings in Chicago, were migrating to or from Canada.
“This is breaking news in the bird world,” said Dr. David Bird, an emeritus professor of wildlife biology at McGill University. He said while there still is not enough evidence to say for sure that climate change is the reason, it is a sound theory that will no doubt spark further study.
Bird said the study uses Bergmann’s rule, in which species tend to be smaller in warmer regions and larger in colder regions.
Ben Freeman, a post-doctoral fellow at the Biodiversity Research Centre at UBC, said the study is extensive and thorough and deals with different species of birds.
In a separate study into bird wingspan changes, local scientist Ronald Ydenberg, a professor of behavioural ecology at Simon Fraser University, reaches a different conclusion.
He has been studying the wingspan of two species of long-distance migratory sandpipers that breed in the Arctic, and what he has discovered is that the wingspan of the western sandpiper has been lengthening, while the wingspan of the other species — the semi-palmated sandpiper (or eastern sandpiper) — has been shrinking.
He attributes the changes to the steady increase in the danger posed by falcons, whose numbers have recovered after nearly being wiped out because of DDT.