Assessing population structure and migratory patterns of White-throated Sparrow (Zonotrichia albicollis) breeding populations in western Canada.

The objective of the present study was to investigate the genetic and migratory differences among White-throated Sparrow populations in western Canada in order to locate the presence of a migratory divide. Deuterium isotopes and molecular markers were used to assess the migratory differences between sparrows west (Central Interior BC) and east (Peace Region BC) of the Continental Divide. Head feather isotopes showed that both populations are overwinter wintering in either the Pacific Coast, New Mexico/Arizona or Colorado/Kansas areas. Microsatellites and mitochondrial markers did not show genetic structure among populations, however tail feather isotopes were significantly different. Analysis of migratory samples is congruent with Peace region birds migrating east of the divide. The Central Interior birds were not detected in any migratory monitoring locations. Data of the present study is congruent with a migratory divide and an east/west migration pattern between Central Interior and the Peace Region populations. --P. ii.