Grant: 14-035R
Project Title: Demographic Assessment of Marine Turtles in the Big Bend Seagrasses and St. Martins Marsh Aquatic Preserves - Year Two
Project Manager: Jonathan Gorham
Organization: Inwater Research Group (Non-Profit Organization)
Grant Amount: $18,900.00
Completion Date: 2015-12-17

Summary: The Big Bend area of Florida's gulf coast has received relatively little attention from sea turtle researchers, primarily due to the lack of nesting beaches in the region. Submerged aquatic habitat in the Big Bend region is characterized by large expanses of shallow seagrass and hardbottom habitats that provide foraging opportunities for loggerhead, green, and Kemp's ridley sea turtles. Our previously funded project from the Sea Turtle License Plate Grant Program (13-010R) identified areas within St. Martins Marsh Aquatic Preserve with a high abundance of Kemp’s ridley and green turtles. During this project we found that 79% of green turtles captured exhibited tumors consistent with fibropapillomatosis (FP). The year two of this project would continue to utilize vessel based visual transects and captures of marine turtles in St. Martins Marsh Aquatic Preserve. The project will directly addresses needs identified in the recovery plans for marine turtles by identifying important habitats and determining the distribution and abundance of sea turtles in coastal and marine environments. The information gathered from this research will help produce a comprehensive set of baseline data for sea turtles in the preserves and will aid in the conservation decisions made by preserve mangers.

Results: Sampling during this report period occurred from June 14 to June 19 and September 28 to October 3, 2014. We conducted 60.36 km of Haphazard Unmarked Nonlinear Transects (HUNTS) and 20.4 km of fixed repeatable transects in the St. Martins Marsh Aquatic Preserve. One hundred and twelve green turtles, 44 Kemp's ridley turtles, and six loggerheads were observed on the HUNTS. Relative abundance for all species was calculated at 2.68 observations per transect kilometer. Observations during the 20.4 km of fixed transects included one loggerhead, 13 green turtles, 35 Kemp's ridley turtles, and one turtle of undetermined species. Total abundance of all species during the fixed transects were calculated at 8.19 individuals per square kilometer. We captured a total of five loggerheads, 44 green turtles, and 54 Kemp's ridley sea turtles. Loggerheads captured ranged in straight carapace length (SCL) from 33.9 to 94.8 cm with a mean of 69.5 cm. Green turtles captured ranged in SCL from 23.8 to 55.9 cm with a mean of 36.0 cm. Kemp's ridley sea turtles captured ranged in SCL from 26.9 to 56.5 cm with a mean of 43.7 cm.