A pragmatic approach for comparing species distribution models to increasing confidence in managing piping plover habitat

Abstract

Conservation management often requires decision-making without perfect knowledge of the at-risk species or ecosystem. Species distribution models (SDMs) are useful but largely under-utilized due to model uncertainty. We used an ensemble modeling approach of two independently derived SDMs to explicitly address common modeling impediments and directly inform conservation decision-making for piping plovers in a heavily populated mid-Atlantic (USA) coastal zone. We summarized previously published Bayesian network and maximum entropy models to highlight similarities and differences in structure, and we compared the relative importance of predictors used. Despite differences in analytical approach, relative importance of factors driving nest-site selection was consistent. Models demonstrated considerable agreement when comparing a binary (suitable/ unsuitable) measure of suitability. Instances of model consensus (i.e., overlapping areas of predicted piping plover nesting habitat between models) provide a stronger "signal" in model results, reducing uncertainty related to biases or errors associated with either model. We tested model accuracy using a common dataset of plover nests initiated within the focal areas between 2013 and 2015, and we examined congruency in model outputs. Nearly, 90% of all nests occurred in areas predicted suitable by at least one model, and at least 33% of the total nests were predicted in areas suitable by both. Because models predominantly agreed on what drives piping plover nest-site selection, areas predicted suitable by a single model should not be discounted. This case study demonstrates how models can effectively inform conservation planning by explicitly identifying the management objective, presenting robust evidence to allow managers to evaluate outcomes of alternative management decisions, and clearly communicating results that address real-world conservation problems. Our results can

Adult piping plover habitat selection varies by behavior

“…On the breeding grounds, plovers transition through a variety of stages, viz., territory establishment and courtship, initiating and incubating nests, tending to chicks, and preparing for southward migration (Elliot-Smith and Haig 2004). Because of different biological and spatial requirements within these stages, such as needing nest sites that are adequately camouflaged, foraging habitat that is accessible for flightless chicks, or mudflats with abundant prey following and prior to migration (Flemming et al 1992, Maslo et al 2019, plovers likely select habitat differently among stages. However, across all breeding stages, adult plover behavior also changes within stage.…”