Population Response of Northern Bobwhite to Field Border Management Practices in Mississippi

Abstract

Empirical relationships of the intensity and spatial extent of field border management required to elicit mea-surable population responses of northern bobwhite are needed. We established 90.5km of herbaceous field borders (6.1 m wide) along row crop field edges on one half of each of 3 -800-ha agricultural landscapes in northeast Mississippi. Mean percentage of row crop fields established in field borders was 6.0%. During 2000-2002, we measured breeding season abundance and fall density on all 3 sites and survival of radiomarked bobwhite on 2 of the 3 sites. We used space-use models of bobwhite habitat composition and configuration to estimate changes in habitat suitability resulting from field border implementation. Breeding season survival did not differ between bordered (S = 37.2, SE = 0.06) and non-bordered (S = 42.7, SE = 0.09; χ 2 1 = 0.001, P = 0.97) sites. Moreover, bordered and non-bordered sites did not differ significantly with respect to breeding season call counts (bordered = 1.0, SE = 0.18; non-bordered = 0.8, SE = 0.27; F1,10 = 0.44, P = 0.22) and fall density (bordered = 0.2 birds/ac, SE = 0.07; non-bordered = 0.1 birds/ac, SE = 0.05; F1,10 = 2.18, P = 0.17). However, field borders increased the amount of usable space on average up to 13.1% on bordered landscapes. The relatively low percentage of field borders established on our sites was not sufficient to elicit measurable population responses of bobwhite. We recommend at least 5-10% of a study area be placed in field border habitats to enhance local bobwhite populations.