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Piping Plover home ranges do not appear to be impacted by restoration of barrier islands and headlands

Abstract

Restoration of barrier island and headland habitats can alter existing and create new habitats, which may impact wildlife occupying these areas such as the threatened Piping Plover ( Charadrius melodus ). We used resight data from banded birds to develop minimum convex polygon (MCP) and kernel density estimates (KDE) of individual Piping Plover home ranges to investigate whether changes in habitat use resulted from restoration activities at Whiskey Island and Caminada Headland, Louisiana. We quantified home range areas for each season and compared changes among pre-restoration, active restoration, and post-restoration phases at each site. We had sufficient sample sizes from Whiskey Island to compare home ranges derived by MCP during the pre-restoration phase to the active restoration phase. However, we did not have enough resight data to analyze post-restoration phase by MCP or any phase by KDE at Whiskey Island. For Caminada Headland, we were able to compare all phases of restoration using MCP, but only had sufficient data to compare pre-restoration and active restoration phases using KDE. Aside from one significant decrease in core (50% isopleth) home range at Caminada Headland when comparing MCPs between post-restoration (∼8 ha) and pre-restoration (∼11 ha) phases, we found no other differences in home range size across phases at either of our study sites. The sum of all evidence generally indicating no change to Piping Plover home range size suggests that barrier island and headland restoration did not have significant positive or negative impacts. The weak response to restoration activities further suggests that birds are using similar or smaller amounts of habitat after restoration is complete and may not need to expand their foraging range following restoration. Further study can help to understand how species of conservation concern respond to coastal restoration efforts, which is critical for establishing comprehensive conservation strategies aimed at species recovery.

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BibTeXRIS

Theodore J. Zenzal, Amanda Nicole Anderson, Delaina LeBlanc, Robert C. Dobbs, Brock Geary, Hardin Waddle. 2025. Piping Plover home ranges do not appear to be impacted by restoration of barrier islands and headlands. https://doi.org/10.1101/2025.03.03.638931

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