Date of Award

Fall 12-2021

Level of Access Assigned by Author

Open-Access Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

Erik J. Blomberg

Second Committee Member

Amber Roth

Third Committee Member

Erin Simons-Legaard

Additional Committee Members

Joseph Zydlewski

Brian Olsen

Abstract

Across temperate regions of North America, migrating animals must contend with seasonally influenced thermal extremes, changing food abundance, and stochastic weather events. Migrating individuals must locate suitable areas, termed stopover locations, to rest and rebuild energy reserves needed to continue migration (Rodewald and Brittingham 2004, Taylor et al. 2011). The American Woodcock (Scolopax minor; woodcock hereinafter) is a migratory forest bird that has experienced long-term population declines (Seamans and Rau 2019). We created the Eastern Woodcock Migration Research Cooperative, including 34 provincial, federal, state, and non-governmental partners, with the goal of describing the migration ecology of woodcock in the eastern portion of its range. We were primarily interested in understanding migration phenology, identifying weather conditions that were associated with migratory departure events, and quantifying survival during migration. Recent advances in transmitter design allowed the cooperative to remotely obtain high resolution locations of migrating woodcock. We deployed 304 satellite-gps transmitters in three provinces and 12 states and collected movement data from 1 October 2017 to 18 June 2020. We begin by describing the phenology associated with migration initiation, timing of stopovers, and termination of migration during fall migration, and the initiation of spring migration and describe the spatial, demographic, and body-conditions based variation in these events. We then built predictive models to estimate the dates associated with fall and spring migration and provide a framework for wildlife managers to evaluate the timing of hunting seasons under current and future harvest regulations. Next, we evaluate the environmental cues associated with migratory departure events and found that age influenced cue selection in the fall and sex in the spring. Furthermore, the specific conditions in which an individual initiated migration could influence the distance an individual traveled in a single migratory flight, but not the pace of migration which was more spported by spatial features. Lastly, we quantified survival of woodcock during migratory periods and found that survival varied by migratory behavioral state, through time, and depending on the season, but was not influenced by age or sex.

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