Assessing the Suitability of Landscapes for Northern Bobwhite

Abstract

Widespread declines of northern bobwhite (Colinus virginianus) populations may reflect habitat alteration at both site and landscape level. To investigate the latter, we quantified landscape composition and pattern throughout Illinois (>145,900 km 2 ) using classified satellite imagery and FRAGSTATS software. We then compared landscape structure with indexes of northern bobwhite abundance using county-level harvest and North American Breeding Bird Survey (BBS) data. Analyses at both scales suggested bobwhite were primarily associated with diverse, patchy landscapes that contained moderate amounts of grassland and row crops and abundant woody edge. These findings were used to develop a PATREC model to identify and map Illinois landscapes potentially suitable for bobwhite. Whether or not such areas actually support good bobwhite populations depends upon site conditions generally not discernable by remote sensing. Nevertheless, knowledge of the extent and distribution of potentially suitable landscapes can enhance and focus management efforts.