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Population declines of disturbance-dependent species due to suppression of natural disturbances are realized across ecosystems. The piping plover (Charadrius melodus; plover), a disturbance-dependent and conservation-reliant shorebird that nests on sandy beaches and barrier islands on the Atlantic Coast, was listed under the United States Endangered Species Act in 1986. In 2012, Hurricane Sandy landed on Fire and Westhampton islands, barrier island nesting sites for plovers in New York, USA. Hurricane Sandy was a natural disturbance in this system, creating abundant nesting habitat. The number of chicks produced by a pair, or a population, is a direct measure of reproductive output, and gaining a better understanding of productivity and chick behavior following large-scale habitat creation may improve plover habitat management and potentially species persistence. We evaluated the effects of landscape features on habitat selection, behavior, and survival of plover broods using logistic regression, generalized linear mixed effects models, and survival models. Plover broods selected flatter sites with less dense vegetation than available at random. Chick foraging rates were highest in moist substrates and were lower in areas of higher nesting plover density. Chick survival was greater for broods that hatched earlier in the breeding season and increased as chicks aged. Generally, providing access to sites with flatter, moist substrates will likely result in higher quality brood rearing habitat on the landscape. Ultimately, vegetation removal and habitat management may be needed to reduce plover nesting density and ensure sufficient habitat, which may in turn improve plover chick survival. Moreover, sustaining natural landscape disturbances such as those resulting from storms, and not taking actions to prevent hurricane-created overwash, will allow these landscape features to persist.

Law enforcement agencies continue to grow in the use of spatial analysis to assist in identifying patterns of outcomes. Despite the critical nature of proper resource allocation for mental health incidents, there has been little progress in statistical modeling of the geo-spatial nature of mental health events in Little Rock, Arkansas. In this article, we provide insights into the spatial nature of mental health data from Little Rock, Arkansas between 2015 and 2018, under a supervised spatial modeling framework. We provide evidence of spatial clustering and identify the important features influencing such heterogeneity via a spatially informed hierarchy of generalized linear, tree-based, and spatial regression models, viz. the Poisson regression model, the random forest model, the spatial Durbin error model, and the Manski model. The insights obtained from these different models are presented here along with their relative predictive performances. The inferential tools developed here can be used in a broad variety of spatial modeling contexts and have the potential to aid both law enforcement agencies and the city in properly allocating resources. We were able to identify several built-environment and socio-demographic measures related to mental health calls while noting that the results indicated that there are unmeasured factors that contribute to the number of events.

Wire cages (i.e., predator exclosures) are frequently used to protect shorebird nests from predation. While exclosed nests often have higher survival than unexclosed nests, concerns exist over whether the conspicuous structures might draw attention of predators, potentially increasing risks to adults and newly-hatched chicks. We present a new approach to investigating predator responses to exclosures and other stimuli at shorebird nests. We used location data from GPS-collared red foxes (Vulpes vulpes) to examine short-term spatial responses of foxes to exclosure setup and hatching at piping plover (Charadrius melodus) nests on Fire Island, New York. We compared mean distances between fox locations and piping plover nests, and the proportions of fox locations within a 100-m buffer of nests, before and after exclosure setup and before, during, and after hatching. Mean distances from fox locations to nests were similar before versus after exclosure setup (x = 641 m before, 675 m after; permutation test for matched pairs, [PTMP], T = 0.28, P = 0.56, n = 9 foxes), before versus during hatching (x = 417 m before, 340 m during; PTMP, T = -0.93, P = 0.18, n = 5 foxes) and during versus after hatching (x = 340 m during, 330 m after; PTMP, T = 1.00, P = 0.84, n = 5 foxes). The proportions of fox locations within 100-m buffers surrounding nests were similar before versus after exclosure setup (x = 0.01 before, 0.03 after; PTMP, T = 0.26, P = 0.53, n = 9 foxes), before versus during hatching (x = 0.04 before, 0.15 during; PTMP, T = -1.44, P = 0.09, n = 5 foxes), and during versus after hatching (x = 0.15 during, 0.14 after; PTMP, T = 0.84, P = 0.80, n = 5 foxes). In 10 of 19 of our individual-level comparisons, there were no significant differences in the distances from fox locations to nests between paired event periods. In the other 9 individual-level comparisons, we found evidence of shifts in fox space use between paired event periods, but no clear directional trend across