Breeding season habitat use and survival of scaled quail

Over the last few decades, scaled quail (Callipepla squamata) populations have been declining throughout the southwestern United States. Despite interest in managing for this species, scaled quail habitat use has been poorly studied, particularly in terms of nest site selection. Appropriate management strategies require a comprehensive understanding of what constitutes habitat, and how choices about habitat use influence survival. We investigated breeding season habitat use and survival of scaled quail in response to vegetation, temperature, time since fire, and anthropogenic structures. We used radio telemetry to identify and monitor nests of marked quail. After nest fate, we investigated nest site characteristics both at the nest bowl and in the area surrounding the nest. We found that scaled quail nested in areas with taller vegetation, greater cover of grass and litter, and warmer microsite temperatures during the day. Relative to the area surrounding the nest, nest bowls had even greater cover of grass, litter, and shrubs, and were significantly cooler during daylight hours. Despite apparent selection for particular nest site characteristics, these were not found to influence nest fate or daily nest survival. From May through July, we collected similar data at locations of non-brooding adults, brooding adults, and stratified random locations. Both brooding and non-brooding adults used locations with greater vertical obstruction and a higher density of tall (≥1.5 m) shrubs. In particular, density of tall honey mesquite (Prosopis glandulosa) was almost 20 times greater at locations of non-brooding adults than at random locations. Both brooding and non-brooding adults showed selection for total mesquite cover, although this selection appeared to be stronger for non-brooding adults. Weather explained more variation in survival than vegetation, time since fire, or anthropogenic structures. Specifically, survival of non-brooding adults, brooding adults, and broods decreased with increasing daily temperature, precipitation, and solar radiation, respectively. These results highlight the importance of vegetation structure and microsite temperature in providing breeding season habitat for scaled quail, and suggest that management resources should be directed towards establishing and maintaining structural and compositional diversity of vegetation