Grant: 19-030R
Project Title: Assessment of Marine Turtle Nesting Habitat at Pocket Beaches in Florida
Project Manager: Kristen Nelson Sella and Dr. Mariana Fuentes
Organization: Florida State University (Research and Educational Institute)
Grant Amount: $16,533.64
Completion Date: 2023-07-21
Summary: Beach armoring, hardened structures placed adjacent to beaches in response to coastal erosion, can cause result in small sections of beach remaining as nesting habitat, forming what are known as pocket beaches. The use of urban pocket beaches in Florida by nesting marine turtles has been documented, but it is not known how much nesting occurs on these beaches as compared to traditional beaches or if the pocket beaches in Florida provide suitable nesting habitat. Thus, the overall aim of this project is to obtain a better understating of the relative importance of pocket beaches as nesting habitat for marine turtles in the state of Florida. To achieve this, the project will: 1) determine the abundance of pocket beaches present in Florida, 2) assess the quality of the nesting habitat in these locations and likelihood of being inundated in the future, and 3) determine the use of pocket beaches by marine turtles compared to adjacent, more traditional beaches. 
Results: Sandy areas between rocky uplands, or natural pocket beaches, provide important habitat for coastal wildlife. On developed coasts, similar sandy areas, called urban pocket beaches, occur in the gaps between properties with coastal armoring (sea walls or revetments). These urban pocket beaches provide important nesting, foraging, and resting habitat for wildlife, particularly on extensively armored beaches. However, it is unclear if urban pocket beaches provide the same function as natural pocket beaches or offer benefits (e.g., reduced risk of inundation or erosion) lost at nearby armored areas. To address these knowledge gaps, we analyzed loggerhead marine turtle nesting patterns and reproductive success to determine if urban pocket beaches represent preferred nesting habitat along armored coastlines. We also determined if nests at urban pocket beaches are more likely than nearby armored and unarmored beaches to be inundated from wave runup, which could alter the incubation environment and nest productivity of marine turtles. The linear extent of urban pocket beaches in Florida was identified, then loggerhead marine turtle nesting success, nest density, and hatching success was compared between urban pocket beaches with armoring and beaches without armoring. We also modeled differences in wave runup exposure at these beaches under current conditions (2016-2019) without and with tropical
storms and future (2060) intermediate-low and high sea level rise scenarios. Overall, pocket beaches account for less than 2% of Florida's nesting beaches with higher abundance on more heavily armored shorelines. Nesting density in pocket beaches were similar to nearby beaches without armoring. However, female turtles were more likely to nest in urban pocket beaches compared to adjacent armored areas, and pocket beach nests had a higher hatchling success rate than unarmored and armored beaches. Our models suggest that exposure to wave runup varies by geographic location, but overall pocket beaches provided viable nesting habitat in all areas surveyed. Thus, managers should advocate for preserving urban pocket beaches on armored shorelines. Read full publication.