Northern bobwhite predator avoidance behavior in response to varying types of threat

Abstract

The flight behavior and cover use of northern bobwhite (Colinus virginianus) have been examined in several studies, but the current data lack quantitative measures of how bobwhites respond to natural threats. We examined aspects of bobwhite behavior in response to 4 threat categories: researcher, hunter, raptor, and mammal. We found that bobwhite flight distance is best predicted by threat type and covey size, and bobwhite flight speed is best predicted by threat type. Bobwhites flushed by the hunter threat and the raptor threat selected for significantly taller obstruction at landing sites than was randomly available, with average heights of 6.2 cm taller (P = 0.034), and 38.1 cm taller (P < 0.001), respectively. Raptor-flushed bobwhites also selected for significantly denser shrub cover (42.2%, P < 0.001) and a lower angle of obstruction (70.4°, P < 0.001) at landing points than was randomly available. In the process of data collection, we also observed bobwhite roost locations have lower visual height obstruction (7.3 cm, P = 0.03), lower shrub intercept (10.1%, P = 0.02), and greater angles of obstruction (18.5°, P = 0.005) than bobwhite diurnal locations; this may facilitate escape from nocturnal mammalian predators. Our results suggest 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 bobwhites but also suggest how a more complete understanding of bobwhite behavior would improve management and conservation efforts. © 2014 The Wildlife Society.