Migratory connectivity and timing for an at-risk Canadian landbird, Eastern Whip-poor-will (Antrostomus vociferus), from two geographically distant breeding areas

Canadian Journal of Zoology, Ahead of Print. Determining the year-round spatial distributions of at-risk avian migratory species is critical for effective conservation. High-precision tracking enables the identification of distant breeding and nonbreeding areas and their connectivity, as well as migratory routes and associated threats. We GPS-tracked two groups of Eastern Whip-poor-wills (Antrostomus vociferus (A. Wilson, 1812)) that breed near the northern edge of their range, in Manitoba and northwestern Ontario ( “west”), and in southern Ontario (“east”), Canada. The western-breeding birds were also ∼5° of latitude farther north than the eastern birds. We aimed to determine the degree of spatiotemporal overlap between the two groups during fall migration and at tropical wintering sites. We found t hat western-breeding birds departed earlier on migration than eastern-breeding birds, but we did not detect a difference in arrival timing to wintering sites. The two breeding groups retained spatial structure during migration, until all routes converged to circumnavigate the Gulf of Mexico. Western -breeding birds overwintered at sites farther south than eastern-breeding birds, consistent with a leapfrog pattern of migration. Quantifying the strength of migratory connectivity in at-risk species can be a first step toward defining breeding populations and informing customized conservation strat egies throughout the annual cycle.
Source: Canadian Journal of Zoology - Category: Zoology Authors: Source Type: research