Anti-predatory behavior of northern bobwhite in the rolling plains of Texas

Northern bobwhites (Colinus virginianus; hereafter bobwhites) are a species of great economic importance but have declining populations range-wide. As a result, bobwhites are a highly researched species. Flight behavior and cover use patterns of northern bobwhites have been examined in several studi...

Full description

Bibliographic Details
Main Author: Perkins, Rebecca
Other Authors: Rollins, Dale, McIntyre, Nancy E., Boal, Clint W.
Format: Thesis
Language:English
Published: 2012
Subjects:
Online Access:http://hdl.handle.net/2346/45392
Description
Summary:Northern bobwhites (Colinus virginianus; hereafter bobwhites) are a species of great economic importance but have declining populations range-wide. As a result, bobwhites are a highly researched species. Flight behavior and cover use patterns of northern bobwhites have been examined in several studies, all of which have contributed to a large set of habitat management recommendations for the species. However, the existing data lack quantitative measures of how bobwhites respond to natural threat, not solely direct human disturbance. I examined aspects of bobwhite behavior in response to four threat categories: researcher, hunter, raptor, and mammalian. I found that bobwhite flight distance is best predicted by threat type, covey size, and wind speed. I found that bobwhites flushed by the hunter threat (P = 0.034) and the raptor threat (P < 0.0001) selected for significantly higher visual obstruction at landing sites compared to availability. Raptor-flushed bobwhites also selected for significantly higher shrub density (P < 0.0001) and lower angle of obstruction (P <0.0001) at landing points than what were randomly available. In the process of data collection I also observed bobwhite roost locations (n=24) to have lower visual height obstruction (P = 0.03), lower shrub density (P = 0.02), and higher angles of obstruction (P = 0.005) than bobwhite diurnal locations. My results verify that bobwhite escape strategies and cover use vary among threat types. These results support current management recommendations of creating a patchwork of vegetation covers for bobwhite, but also indicate the importance of understanding of bobwhite behavior to improve management and conservation strategies. To examine how bobwhites respond to a raptor threat, we used a trained northern goshawk (Accipiter gentilis), a bird often used for falconry. The practice of falconry is over 2000 years old. It is a form of hunting wild quarry in its natural state and habitat by means of a trained raptor. Researchers, specifically when ...