GREEN TURTLE
RESEARCH
PROJECT OVERVIEW
In Brevard County, an isolated shallow nearshore reef resides from the shoreline out to approximately 150m along a 14.5-kilometer stretch of beach. East Coast Biologists, Inc. began a study of the marine turtle population using the nearshore hardbottom reefs in this area in 2003. Researchers observed juvenile green turtles and, occasionally, a loggerhead sea turtle over the nearshore reefs.
Preliminary genetic research conducted by University of Georgia’s Warnell School of Forestry and Natural Resources indicates that the natal origin of the juvenile green turtle population sampled from this area were hatched from as far away as beaches in Costa Rica. To better understand the importance of this habitat, researchers placed acoustic transmitters on 15 juvenile green turtles to learn whether turtles are “residents” or “transients” just passing through. Results of acoustic tracking and recapture data indicated juvenile green turtles use this nearshore habitat anywhere from 30 days to a year or longer.
NUTRITIONAL STUDY
Juvenile Chelonia mydas
We are pleased to announce the Sea Turtle Grants Program has awarded East Coast Biologists, Inc. with funding to support our study to determine the nutritional value (e.g., protein, lipid, carbohydrate) of macroalgae consumed by juvenile green turtles. Baseline data on turtle foraging are necessary to adequately measure habitat modification wrought by climate change, coastal development, and pollution inputs. Data from this study will contribute to our baseline knowledge for growth and health of wild populations and support sea turtle rehabilitation efforts.
The Sea Turtle Grants Program is funded from proceeds from the sale of the Florida Sea Turtle License Plate. Learn more at www.helpingseaturtles.org.
ACOUSTIC STUDY
Juvenile Chelonia mydas
One of the greatest threats to the recovery of threatened and endangered sea turtle species is the loss of adequate habitat necessary for foraging, shelter, and refuge from predators. The focus of the current acoustic study is to determine if and how juvenile green turtles use recently deployed (2019) artificial reefs that were designed to mitigate possible impacts to nearshore reef habitat caused by beach nourishment as part of Brevard County's Beach Restoration Project. This study examines the viability of using artificial reefs to help mitigate for sea turtle habitat impacted by shoreline restoration and beach nourishment activities.
Mitigation reefs were built in advance of the Project, which while enhancing the nesting beach habitat for marine turtles, will inadvertently bury a portion of inter-tidal and shallow subtidal (0-3m water depth) hardbottom reef habitat used by juvenile green turtles. The mitigation reefs (installed in approximately 5 m water depth) were purposefully designed to provide suitable substrate for the attachment and growth of foraging resources (macroalgae) and create refuge (ledges) for small size-class green turtles (mean ~30 cm SCL). During preliminary observations, juvenile green as well as loggerhead (adult and subadult life stages) sea turtles were seen on and around the mitigation reefs. Data from these studies help inform coastal managers and policymakers on the effectiveness of artificial reef design and structure for sea turtles.