DescriptionConservation action and habitat restoration for threatened and endangered species are often guided by anecdotal evidence. Limited time and resources are wasted on ineffective strategies, or in some cases, on management that is detrimental to the target species. Therefore, rigorous scientific study must be easily translatable into pragmatic conservation directives. For the Atlantic Coast piping plover (Charadrius melodus), a threatened beach-nesting shorebird, two major threats exist for the recovery of the species -- habitat degradation by beach stabilization practices and human disturbance, and intense predation pressure by the introduced red fox (Vulpes vulpes). This dissertation employs robust statistical methods to: 1) analyze piping plover nesting and foraging behavior, and 2) evaluate the effectiveness of predator exclosures to present evidence-based recommendations for the restoration of breeding habitat and the optimization of reproductive success.
Piping plover nests primarily occur in four distinct habitat conditions defined by percent shell and pebble cover, and distance to nearest dunes and high tide line. Characteristics also vary depending on where the nest is initiated (backshore, overwash fan, primary dune). I translate these results into practical restoration target parameters and identify threshold values to assist managers in maintaining suitable nesting habitat. Restoration projects must also include accessible high quality foraging habitat to bolster reproductive success. Plover chicks foraged at higher rates and spent less time being vigilant or fleeing from threats at restored tidal ponds than at other potential foraging habitats. This result suggests that the study ponds offered adequate prey biomass, were visited less frequently by humans, and provided proximate refuge from approaching predators. The foraging models I created were validated externally and are applicable for evaluating future restoration projects.
Finally, long-term nest monitoring data indicate that predator exclosures do increase nest hatching success. Electrified exclosures are effective under certain conditions, but at sites with high fox density and human disturbance, nest abandonment becomes sizeable. While the direct cause of abandonments remains unclear, these results will assist managers in making informed decisions on using this technique. These science-based directives can help to create effective habitat designs and conservation strategies for this species.