Migratory Connectivity in the Rusty Blackbird: Isotopic Evidence from Feathers of Historical and Contemporary Specimens

The condor

Keith A. Hobson¹ 

关键词: deuterium;    Euphagus carolinus;    migratory connectivity;    Rusty Blackbird;    stable isotopes;   

DOI  :  10.1525/cond.2010.100146

学科分类：动物科学

来源: Central Ornithology Publication Office

【 摘 要 】

Abstract. The Rusty Blackbird (Euphagus carolinus) has declined dramatically across its range in North America since at least the 1960s, but the causes for this decline are unknown. We measured ratios of stable hydrogen isotopes (δD) in feathers collected from Rusty Blackbirds wintering in the Mississippi Alluvial Valley (n = 255 birds) and the coastal plain of South Carolina and Virginia (n = 281 birds), 2005–2009, to estimate the region of origin of birds wintering west and east of the Appalachians, respectively. We also measured δD values in feathers from all available museum specimens collected from 1879 to 1990 in these same two regions (n = 190 birds). Isotopic values support migratory connectivity in this species with breeding populations in the western and central boreal forest migrating through a central or Mississippi flyway and those breeding in the eastern boreal forest migrating to a winter range east of the Appalachians. We detected little long-term change in the breeding origins of modern a...

【 授权许可】

CC BY