Forest songbirds in peril

Walking through York’s Keele campus anytime between August and October you are likely to see dozens of species of migratory forest birds making their way south. York Professor Bridget Stutchbury, Canada Research Chair (CRC) in Ecology and Conservation Biology, is currently monitoring the migratory patterns and health of forest songbirds that summer in Southern Ontario and winter in Mexico, Belize and Panama.

Right: Bridget Stutchbury

These tiny birds face a daunting journey each year over thousands of miles, through various physical and political climates; their numbers are dwindling and several populations are verging on complete devastation.

“Next to nothing is known about the effects of mass deforestation on the lives and habits of these birds, especially on the wintering grounds,” says Stutchbury, whose research on migratory birds began during her graduate studies at Queens and Yale. Following post-doctoral work at the Smithsonian Institute, she became a professor at York; it was here that Stutchbury began to specifically study forest songbirds and the links between species decline and habitat loss

Funds from an NSERC Discovery Grant, Premier’s Research Excellence Award, and the Molson Foundation finance the work that Stutchbury and her team of graduate students are doing both here and in the South. Their approach is deliberately widespread because almost all forest birds face population decline due to habitat loss. As opposed to many researchers that would choose one species to study in minute detail, Stutchbury is concerned with the broader understanding of ways in which all migrant species are affected.

“We like to spread ourselves around,” Stutchbury says. “We study both in Ontario and in the wintering grounds. It gives us the opportunity to suit the student to the project.” One student is using physiological tools to measure stress hormones in birds. This is a way of asking the birds if the habitat they occupy is high quality. So far, the project’s findings confirm Stutchbury’s hypothesis that birds in large protected rainforests in Mexico (similar to National Parks) have lower levels of stress hormones than those living in leftover patches of forest and scrub that are the typical habitat found in most of Central America.

Locally, Stutchbury leads one of several teams funded by the Canadian Wildlife Service, and the World Wildlife Fund, to track endangered species in Ontario. With Post-Doctoral Fellow Bonnie Woolfenden, Stutchbury monitors the Acadian Flycatcher, which is restricted to Southern Ontario from Hamilton to Long Point.

Left: The Acadian Flycatcher

This study, of the forty or fifty remaining pairs of Acadian Flycatchers, monitors nesting success, predation, survival, and habitat. Stutchbury and Woolfenden use modern genetics prototyping, to determine how distinctive the Ontario population is, and whether or not it is self-sustaining. The combination of molecular biology with genetics and ecology in the Acadian Flycatcher project is both innovative and interdisciplinary.

This work is done in Stutchbury’s Molecular Ecology Lab. The lab, which cost approximately $250,000 in renovation and equipment, is part of Stutchbury’s CRC award, funded by the Canadian Foundation for Innovation. Much of the equipment is the same as what is used in Cancer research, hospitals and the medical community at large.

“What we hope to determine,” says Stutchbury, “is whether or not our Canadian population is able to sustain itself over time. We are tracing the gene flow through generations of Acadian Flycatchers to see how much of the population is mixing with birds from the United States across Lake Erie.”

One possible ramification of a non-sustaining Canadian population of these birds is that eventually none will return to summer in Canada.

“It is encouraging to see the Government taking an active interest in endangered species by funding work like ours,” Stutchbury says. Equally encouraging is that York is a link on the chain, both of the migratory path of forest songbirds, and the pursuit of their preservation in Canada.

Shoshana Green, a York graduate student in English who writes about research at York University, sent this article to YFile.