Optimizing conservation benefits for threatened beach fauna following severe natural disturbances

Abstract

Wildlife on sandy beaches is often constrained by transformation of natural areas for human use, and opportunities for acquiring or restoring new habitat are rare. Storms can often force changes in land use naturally by re-shaping coastal landforms, thereby creating high quality habitat; yet, wildlife requirements are seldom considered in post-storm recovery planning, and conservation practitioners lack suitable evidence to argue for the protection of habitats freshly formed by storms. Here we used a maximum-likelihood spatial modeling approach to quantify impacts of Hurricane Sandy (mid-Atlantic United States, October 2012) on nesting habitat of four bird species of conservation concern: American oystercatchers, black skimmers, least terns and piping plovers. We calculated the immediate storm-created changes (loss, persisting, gained) in nesting habitat under two levels of conservation protections: the current regulatory framework, and a scenario in which all potential habitats were under conservation protection. Hurricane Sandy resulted in apparent large gains for least terns (+181 ha) and piping plovers (+289 ha). However, actual gains were reduced to 16 ha for plovers and reversed for least terns (net loss of 6.4 ha) because newly formed habitat occurred outside existing reserve boundaries. Similarly, under the current management framework, black skimmer nesting habitat decreased by ~164 ha. We also tested whether birds benefited from newly created nesting habitat by identifying nest and colony locations for three years following Hurricane Sandy. All species overwhelmingly nested in habitat that existed prior the storm (76-98% of all nests/colonies); only a small percentage (≤17% for all species) occupied newly created habitat. We conclude that static spatial conservation efforts fail to capitalize on potentially large gains resulting from storms for several species and recommend flexible spatial conservation investments as a key input in post-storm recovery planning.

Keywords: Beach-nesting birds; Climate change; Habitat conservation; Species distribution modeling; Wildlife management.