Swifts' migratory behavior may have conservation implications
Resembling swallows but more closely related to hummingbirds, swifts have unique migratory behavior, roosting for days at a time in chimneys or hollow trees along their migratory route in groups of hundreds or thousands of individuals. Little is known about whether groups that travel and roost together during migration are all from the same wintering site or are made up of individuals from across their winter range. A 2012 mortality event in British Columbia that killed more than 1,300 migrating swifts provided researcher Matthew Reudink of Thompson Rivers University and his colleagues with the opportunity to determine where the birds had spent the winter. Their results, forthcoming in The Condor: Ornithological Applications, suggest that the birds in the roost all came from the same two or three wintering sites. Bird breeding populations strongly connected to specific wintering areas may be more vulnerable to population declines, so this has important implications...