Factors affecting piping plover (Charadrius melodus) nest site selection following landscape and predator community changes

The dynamics of coastal landscapes following major storm events and human interventions significantly impact nesting habitat use by species like the piping plover (Charadrius melodus) along Atlantic coastlines. Our study focused on Fire Island, New York, assessing changes in vegetation succession, plover nesting habitat selection, and suitable nesting habitat availability from 2010 until eight years after Hurricane Sandy. We analyzed classified imagery to quantify vegetative cover changes across the landscape and at nest sites. Results showed an increase of 11.5% change in vegetative cover across the study area, and nest sites experienced an increase in vegetation cover from 0.1% to 6.2% between 2015 and 2020. Selection for four habitat variables (i.e., distance to ocean, least-cost distance to bay, elevation, backshore width) was consistent throughout the study, but post-hurricane nests were situated farther from development and closer to bay areas (Euclidean distance) compared to pre-hurricane. Moreover, suitable nesting habitat peaked immediately post-stabilization but declined in subsequent years. Understanding these landscape shifts provides insights into species prioritization of habitat characteristics during nesting. Piping plovers face predation threats during breeding seasons while balancing consideration of the aforementioned habitat considerations, leading to specific nest placement strategies. Our study examined the relationship between nest site selection and the area visible from nests (viewshed) and evaluated its addition in nest site selection models including habitat variables. Piping plovers exhibited a preference for nest sites with increased predator visibility compared to random selection, indicating a strategic selection process. Initially influential (β = 0.43; CI = 0.28 – 0.58), the role of this predator visibility ('viewshed') diminished (β = -0.13; CI = -0.23– -0.04) as the landscape underwent ecological succession. Topographic variation caused greater visual obstruction at nest sites than vegetation. This study on piping plovers offers insights into the interaction between landscape changes, habitat selection, and predator visibility. The evolving importance of viewshed in nest site selection underscores the dynamic nature of nesting strategies in response to changing environments, and incorporation of this variable can improve the predictive ability of other models as it did for this study. These findings have broader implications for ground-nesting bird species and highlight the importance of considering landscape changes and predator visibility in land management strategies to safeguard vulnerable avian populations.