Selman, W. and Collins, S.A., 2018. Observations of wintering piping plovers (Charadrius melodus) positively associated with rock breakwater-influenced shorelines in southwestern Louisiana.

Much of the coastline in southwestern Louisiana is undergoing high rates of shoreline erosion, but long-term plans are to armor the majority of this shoreline with offshore rock breakwaters. This area is also considered critical wintering habitat for Piping Plovers (Charadrius melodus). However, to date, little information is available to assess the influence of these shoreline protection measures on Piping Plovers. From 2009 to 2010, three experimental breakwater sections were built along the shoreline of Rockefeller Wildlife Refuge (RWR) in southwestern Louisiana to determine their effectiveness at combating shoreline encroachment. Thereafter, annual Piping Plover surveys were conducted from 2013 to 2017 at RWR along ∼14.5 km of shoreline inclusive of the test sections. Observations included 89 total Piping Plovers in the 5 survey years, and 56 of these (total mean 63%; annual range 33–94%) were observed immediately behind or closely associated with all three rock breakwater test sections (∼6% of the shoreline surveyed). Breakwater sections, regardless of construction type, supported higher Piping Plover densities than unprotected shoreline. However, it seems that only one of these test sections will be economically viable in the long-term to protect shorelines. Offshore segmented breakwaters may positively benefit wintering Piping Plovers given that they are designed appropriately and permit limited overwash to maintain an open shoreline behind the structure (i.e. no vegetative encroachment). However, shoreline stabilization measures could be a trade-off that benefits some shorebirds (e.g., Piping Plovers) but negatively affects others that prefer mudflats (e.g., Long-billed Curlew [Numenius americanus]).