Searching for and Monitoring the Nests of Imperiled Grassland Birds: Recommendations from the Grand River Grasslands of Iowa

Grassland birds are the most imperiled avian group in North America, with greater than 50% abundance declines since 1970. Studies examining factors that impact habitat preferences, habitat selection, and reproductive success are critical to developing effective conservation and management plans for these species. These studies often involve searching for and monitoring nests in grasslands, which requires a unique set of skills and protocols not always comparable to methods used in other habitats. In this paper, we provide recommendations and best practices for field studies of grassland birds based on our experience studying songbirds in the Grand River Grasslands of southern Iowa,We review search methods (e.g., behavioral searching and rope dragging), monitoring protocols (i.e., nest visits, filming procedures, weighing, and tarsus measurements), nest vegetation sampling, and provide descriptions to aid in nest and nestling identification, with a particular focus on six obligate grassland species. In addition, we provide photographs of nests and associated eggs and nestlings for six species, as well as time-series photos of development to aid in aging nestlings. We recommend researchers carefully consider procedures for monitoring nests of grassland birds and keepi