Extrinsic factors similarly affect nest survival of a threatened shorebird in natural and human-created habitats

Knowledge of factors that influence nest survival can inform effective conservation management for imperiled avian species. Habitat availability and quality are common priorities of conservation efforts, and climate and interspecific associations can also affect survival rates. In the lower Platte River system of eastern Nebraska, USA, Piping Plovers (Charadrius melodus, hereafter plovers) nest on river sandbars and different types of human-created off-river sites (i.e., sand and gravel mines, housing developments, and transitional sites) that are unique within the Northern Great Plains breeding population. However, off-river habitat may not be suitable for plover nesting long-term because of reduced habitat availability on both river sandbars and off-river sites. We evaluated plover nest survival at off-river and sandbar sites using data from 2008 to 2023 (n = 285). In addition, we examined the effects of extreme temperatures, proximity to conspecific and Interior Least Tern (Sternula antillarum athalassos, hereafter tern) nests, and temporal factors on nest survival. Plover nest survival did not differ between off-river sites and sandbars or amongst different off-river site types. Daily nest survival was 0.9818 (95% CI = 0.9729–0.9878) from 2008 to 2013 (unexclosed; n = 87) and 0.9950 (0.9918–0.9970) from 2014 to 2023 (exclosed; n = 198). Nest survival increased with the proportion of above average temperature days, increased with proximity to neighboring tern nests, and decreased with later nest initiation dates. Therefore, prioritizing early season nests, recognizing the benefits terns provide to plover nest survival, and monitoring the effect of climatic trends may aid future conservation efforts. Finally, as nest survival at off-river sites is comparable to sandbars, the predicted decline of habitat provided at off-river sites may reduce the overall breeding productivity and abundance of plovers in the lower Platte River system with ramifications to broader population viability.