Golden-winged Warbler body fat and blood parasites are associated with anthropogenic and environmental habitat metrics

. The extent of early successional vegetation communities is declining worldwide. Sometimes species use early successional vegetation communities associated with anthropogenic development (e.g., rangeland, cropland, transportation corridors, aggregate mines), given that, at face value, these ecosystem types can share many of the same characteristics (e.g., lack of mature trees). This may have a negative impact on species’ health by lowering access to resources or by increasing exposure or susceptibility to vectors carrying disease agents leading to infections. We investigated whether proximity to anthropogenic development had a negative impact on several health metrics of a threatened, early successional species, the Golden-winged Warbler ( Vermivora chrysoptera ). Golden-winged Warblers with more rangeland/grassland within 200 m of their capture location were more likely to be infected with Haemoproteus parasites, whereas those with greater marsh cover within 200 m of their capture location were more likely to be infected with Leucocytozoon parasites, and those near rivers had higher body-fat scores. As infection prevalence and body-fat scores may have an impact on avian fitness, the variable response of these land-cover types indicates an additional conservation concern for this threatened species.