Comparative Occupancy and Habitat Associations of Black-and-White (Mniotilta varia) and Golden-Cheeked Warblers (Setophaga crysoparia) in the Juniper-Oak Woodlands of Central Texas

The golden-cheeked warbler (Setophaga chrysoparia) and the black-and-white warbler (Mniotilta varia) breed in the deciduous/evergreen woodlands of central Texas. The golden-cheeked warbler is endemic, while for the geographically widespread, black-and-white warbler, these woodlands represent the southwestern terminus of the breeding range. To estimate relative abundance and to compare habitat associations, we estimated occupancy, corrected for probability of detection, for both species using replicated point-count surveys of 36 survey stations at each of six sites within the Balcones Canyonlands Preserve Travis Co. TX. Model selection using an a priori, set of candidate models suggested that the probability of detection differed among warbler species and study sites and both species were influenced by time of season, time of day, and habitat characteristics of the survey station—slope and canopy cover. Naive occupancy estimates suggested that occupancy of black-and-white warblers was much lower t...