Raptor abundance and northern bobwhite survival and habitat use

Wildlife Society Bulletin
By: , and 

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Abstract

Predation risk has a profound influence on prey behavior and habitat use. The Rio Grande Plains ecoregion of Texas, USA, provides a unique opportunity to investigate changes in prey behavior because the ecoregion experiences a high influx of raptors every year during autumn migration. We used an 8-year data set (2000–2008) of radiocollared northern bobwhites (Colinus virginianus) and raptor abundance to test the hypothesis that bobwhites responded to increased raptor abundance via changes in woody-cover use at the home-range scale. Bobwhite survival was negatively correlated with raptor abundance, with red-tailed hawks (Buteo jamaicensis), and northern harriers (Circus cyaneus) accounting for 51% of the variability in bobwhite survival (P < 0.010). However, we documented no change in the amount of woody cover used by bobwhites in their home range between the raptor migration (6.6% ± 0.5%; n = 73 bobwhites) and non-migration periods (7.1% ± 0.4%; n = 105 bobwhites; P = 0.490). In addition, bobwhites that survived the raptor migration period used similar amounts of woody cover within their home range (6.3% ± 0.6%, n = 58 bobwhites) compared with those dying during the migration period (6.8% ± 0.4%, n = 100 bobwhites; P = 0.530). Our data suggest that bobwhites do not alter their use of woody cover at the home-range scale in response to increasing raptor abundance, but this does not preclude increased use of woody cover at the point-of-use scale.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Raptor abundance and northern bobwhite survival and habitat use
Series title Wildlife Society Bulletin
DOI 10.1002/wsb.476
Volume 38
Issue 4
Year Published 2014
Language English
Publisher Wildlife Society
Publisher location Washington, D.C.
Contributing office(s) Coop Res Unit Atlanta
Description 8 p.
First page 689
Last page 696
Country United States
State Texas
Other Geospatial Rio Grande Plains
Online Only (Y/N) N
Additional Online Files (Y/N) N