Restoration of Louisiana’s vanishing barrier islands is an important component of coastal management planning. Preventing erosion of back barrier saltmarsh on these islands is a major focus of the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA); however, restoration efforts may prioritize mitigation of island erosion over recreation of lost wildlife habitat. Here, we investigate the success of saltmarsh restoration in creating wildlife habitat on two Louisiana barrier islands, using marshbird presence as a metric of restoration success. Back barrier saltmarsh was replanted on Whiskey and Raccoon Island between 2009-2013. In 2016 and 2017, we measured marshbird occupancy over four seasons through use of 43 acoustic recording units (ARUs) and complementary point counts. Sampling efforts were divided between restored and intact marsh patches, with the latter serving as reference habitat. ARUs were set to record for 10 minutes, 3 times daily to cover primary vocalization periods of target species. A suite of 12 marshbird species was developed to evaluate habitat quality. Key habitat characteristics were evaluated at each sampling point, including vegetation type, standing water depth, and distance from habitat edge. We predicted higher species diversity in intact marsh patches resulting from higher habitat quality of mature vegetative communities.
Results/Conclusions
Results between islands were mixed. We found significantly higher species diversity Whiskey Island in restored marsh, with vegetation type as the highest predictor of species diversity. Whiskey Island also had significantly higher avian diversity in both restored and intact marsh patches than did Raccoon Island, indicating that restoration efforts had different outcomes between the two islands. Our results indicate that saltmarsh restoration is not always successful in creating wildlife habitat, and that long-term follow-up assessments to evaluate ecosystem functioning should an integral component of barrier island restoration planning.