Modeling Migration and Citizen-Science Data to Estimate Golden Eagle Abundance in Eastern North America

• Main Author: Dennhardt, Andrew J.
• Format: Text
• Language: unknown
• Published: The Research Repository @ WVU 2014
• Subjects: Ecology; Conservation biology; Wildlife conservation; Aquila chrysaetos; golden eagle
• Online Access: https://researchrepository.wvu.edu/etd/109; https://doi.org/10.33915/etd.109; https://researchrepository.wvu.edu/context/etd/article/1112/viewcontent/29555_Dennhardt_wvu_0256O_10216.pdf

Understanding animal movements is fundamental to ecology and conservation, yet direct measurement of movements of birds is both challenging and costly. Raptor populations are especially difficult to monitor, but movement models can provide information toward this goal. The golden eagle (Aquila chrysaetos canadensis) in eastern North America is a species of regional conservation concern, and little is known about its population ecology, movements, or behavior. Because of their rarity and role as apex predators, improving monitoring of this small population is of great importance. Similar to using movement models to help improve monitoring, developing new methods to estimate the size of wildlife populations is also important to ecology and conservation.;In my first chapter, I simulated autumn migration of golden eagles in Pennsylvania, USA based on regional topography, eagle flight behaviors, estimated uplift, and a principal axis of migration. In total, I modeled 6,094 flight routes, averaging 2,191 (+/- 1,281; +/- SD; range: 3 - 5,373) moves. I found that 71% of my simulations intersected the Ridge and Valley physiographic province of the central Appalachians. Simulations were spatially comparable to historic, flight route data collected via telemetry. In my model, orographic uplift was significantly stronger and more frequently occurring than thermal uplift (Welch's two-sample t = -560.13, df = 43,059,702, p < 0.0001), and uplift values were not correlated with the number of simulated movements (orographic, Pearson's r = -0.015 and thermal, r = 0.003). I used output from my simulations to select sites and collect field data in new areas concentrating golden eagles on migration. This not only preliminarily verified my modeled predictions, but it also allowed me to locate new, potential monitoring sites for migrant golden eagles. I also compared output from my migration model to that of another model, to evaluate the influence of topography, spatial relationships with hawk-count sites, and role of scale in ...