The Effects of Beach Restoration on Marine Turtles\u27 Nesting in South Brevard County, Florida

The south Brevard coast of Florida is a major nesting ground for the Atlantic loggerhead turtle (Caretta caretta). A beach restoration project was completed in the winter of 1980-81 at Indialantic and Melbourne Beach. A study was conducted to investigate the effects of beach restoration on marine turtle nesting during the summer months of 1981 and 1982. A 3.1 km restored beach study area and two control beach study areas, each 3.1 km in length and consisting of natural beach sands, were established. The entire study area (9.3 km) was monitored for nesting and non-nesting emergences (false crawls) and a tagging program was established. The objectives of the study were to determine the effects of the restoration project on the nesting behavior of adult female turtles, and to develop an understanding of the effects of restored beach sands on the survival of marine turtle eggs and hatchlings. During the 1981 nesting season 2,766 marine turtle emergences were recorded. The nesting success rates (nesting emergences/total emergences x 100) for 1981 on the north control beach and the south control beach were 54% and 51% respectively, whereas the restored beach had a statistically significant lower nesting success of 28%. This reduction of nesting success was attributed to a compact substrate that was markedly less friable than the sands of the control beaches. In 1981, the turtles emerging to nest in the restored area often displayed aberrant digging behavior when they encountered the compact sand. By the following summer of 1982, it was evident that the restored beach substrate was less compact. The nesting success for 1982 in the restored beach (46%) rose to a level equal to that of the control beaches (48% and 46%). A total of 3,144 marine turtle emergences were recorded in the 1982 nesting season. To study the effects of beach restoration on the eggs and hatchlings, nests were marked, left to incubate on the beach, and later excavated to determine hatch success. Hatch data and hatchling emergence data were collected on 30 clutches in each of the three beach sections for both the 1981 and 1982 seasons. No significant difference was found between the hatch percentage for the restored beach and the hatch percentages for the control beaches in either study year. The hatchling emergence data, which would indicate the hatchlings\u27 ability to emerge from the sand, indicate no significant difference between the restored beach and control beaches for 1981 and 1982