Differences in Movement and Habitat Use Between Two Call Types of Red Crossbills скачать в хорошем качестве

Differences in Movement and Habitat Use Between Two Call Types of Red Crossbills

The Red Crossbill is a species complex containing 12 vocal, or call types in its North American range. Specialization to key conifers during periods of late winter scarcity has been the primary theory proposed to explain the evolution of these call types, yet the ecological differences between them remain elusive. Studies have shown different call types frequently overlap in breeding and nonbreeding distributions and are observed associating with many resources beyond their key conifer species, even during the critical periods. By assessing resource use and habitat associations of these call types and the associated movement patterns, Konshau will discuss how his research shows that Type 2 and Type 5 Red Crossbills show quite different patterns of occurrence in an area of frequent overlap in northwestern Wyoming. In addition, he will explain how habitat associations, migratory distance, and the associated behaviors could provide a barrier to gene flow between these populations. The findings of Konshau’s research will add to a small but growing body of literature on nomadic migration and adaptive radiation.