Estimating the response of wildlife communities to coastal dune construction

Coastal ecosystems worldwide are being impacted by sea-level rise caused by climate change. As mitigation efforts increase to protect these threatened ecosystems, a deeper understanding of how wildlife adapt to coastal management techniques is needed. We monitored three constructed sand dunes (built in 2010 and 2014) and two natural dunes in central Florida from June 2015 through June 2016 to assess the impact of dune construction as a management technique on terrestrial vertebrates. Specifically, we tested if constructed dunes accumulated and maintained similar community composition and species richness to natural dunes. We used AHDriFT, a game camera-based trapping technique, to monitor terrestrial wildlife communities in both the natural and human-modified landscapes. After 4502 camera nights, we documented 2537 unique photo-capture events, comprised of 33 different species. Species communities were compared by constructing species accumulation curves for each dune type, and by modeling community similarity through multivariate hierarchical clustering. Species accumulation curves overlapped among all dune types, and the cluster analysis showed no pattern separating natural and constructed dunes. However, PERMANOVA found a difference between constructed and natural dunes, which was verified by a NMDS ordination that separated out constructed and natural dunes. Differences between dunes was likely driven by rare species, as commonly observed species overlapped across all dunes, including one protected species. Given the similarity between overall species richness, and that differences in community composition may be due to microhabitat variation and species rarity, we conclude that constructing dunes to increase coastal resilience does not negatively impact endemic wildlife in coastal zones and may provide suitable habitat for many wildlife species.