Migratory routes and stopover regions of eastern breeding veeries (turdidae: catharus fuscescens) as revealed by archival light-level geolocators
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Nearctic-Neotropical migrant passerines have experienced population declines presumably largely due to habitat loss and degradation on both the wintering and breeding grounds. Only recently have these declines been attributed in part to the loss of suitable stopover sites available during migration. Stopover sites of high ecological quality are essential along an ecological barrier in order to provide areas for migrants to rest and refuel. The identification and conservation of high quality stopover sites has become a research priority; however, until recent advances in technology it was difficult to identify these sites without quantitative field surveys. Archival light-level geolocators are the only technology that allows ornithologists to recreate the daily positions of small songbirds (<50g) throughout their annual cycle. The focus of the present research was to further our knowledge of the annual movements of the Nearctic-Neotropical migratory species, the Veery (Catharus fuscescens), through the use of miniaturized tracking technology. My objectives were to (1) identify important stopover regions used by migrating Veeries, and (2) identify important migratory flyways between the Veery’s breeding and wintering grounds. I used kernel density estimations and hot spot analysis to identify important stopover regions used by two distinct eastern breeding populations and compared the results of the different analyses. I identified differences in stopover regions used during migration on the basis of age, sex, and seasons. I also identified the migratory routes taken by 58 individuals over an eight-year period and found that age and sex did not significantly affect the migratory routes taken during migration; however, I did find that the migratory routes varied greatly between years with respect to the path taken by individuals preparing to cross the Gulf of Mexico. My results highlight the importance of long-term geolocator studies to furthering our understanding of migratory connectivity. Also, through this study, I began establishing a potential framework for the identification of important stopover regions for Nearctic-Neotropical migrants in general. This research will enable conservationists to make more informed decisions regarding the stopover regions to prioritize for protection in future long-term conservation planning efforts.