Spring phenology of ecological productivity contributes to the use of looped migration strategies by birds.

ABSTRACT: Migration is a common strategy used by birds that breed in seasonal environments. The patterns and determinants of migration routes, however, remain poorly understood. Recent empirical analyses have demonstrated that the locations of two North America migration flyways (eastern and western) shift seasonally, reflecting the influence of looped migration strategies. For the eastern but not western flyway, seasonal variation in atmospheric circulation has been identified as an explanation. Here, we test an alternative explanation based on the phenology of ecological productivity, which may be of greater relevance in western North America, where phenology is more broadly dictated by elevation. Migrants in the western flyway selected lower-elevation spring routes that were wetter, greener and m

SUBMITTER: La Sorte FA 

PROVIDER: S-EPMC4173673 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature