Leatherback sea turtles are listed as vulnerable. These animals represent the largest extant reptile, with the largest animal recorded measuring 305 cm in total length and weighing 916 kg. They have the widest natural range of the sea turtles and are highly migratory, with some animals traveling over 10,000 miles per year.
Female leatherbacks reach sexual maturity around 15 years of age and nest every 2 to 3 years. These turtles can lay between 5 and 12 nests in a reproductive year, with an average of 80 eggs per nest. Leatherbacks are unique in that they lay smaller infertile eggs atop the larger fertilized eggs before covering the nest.
The leatherback nesting season on St. Kitts runs from February through July, with hatchlings emerging through the end of September and beginning of October. Leatherbacks prefer the Atlantic side of the island for nesting, with Keys and North Friars being the highest density nesting beaches on the island. Nesting does occur on the Caribbean side of the island, although not as frequently.
Leatherbacks (Dermochelys coriacea)
Leatherback female returning to the ocean following a nesting event on Keys Beach, St. Kitts. Photo by Kimberly Stewart. All rights reserved.
Hawksbills (Eretmochelys imbricata)
Hawksbills have been exploited for centuries because of their beautiful shell. Over-harvesting these turtles has resulted in a massive decline in their population; they are currently listed as critically endangered.
Adult animals generally weigh between 45-68 kg and have a shell length of 63 to 90 cm. Adults do not reach sexual maturity until they are 20 to 40 years of age and adult females only nest every 2 to 3 years. They return to their natal beaches and lay an average of 5 nests in a reproductive season, with each nest containing 100 to 200 eggs. Hawksbills nest primarily under beach vegetation such as sea grape (Coccoloba uvifera) and Machinel trees (Hippomane mancinella).
The hawksbill diet is comprised almost entirely of sponges, with a small contribution by other invertebrates. Hawksbills serve as keystone predators in their coral reef habitat by maintaining biodiversity and determining the structure in coral reef ecosystems.
Hawksbills prefer the Caribbean side of the island for nesting but occasionally nest on the Atlantic side of the island each year. Hawksbills primarily nest on St. Kitts from July through February; however, sporadic nesting can occur year round. Foraging hawksbills can be seen year round in the near shore waters.
Foraging hawksbill sea turtle. Photo by Jason Hanley. All rights reserved.
Green sea turtles are listed as endangered worldwide. They reach an average of 1 meter in length and weight of 136 kg. Greens reach adulthood at 20 to 40 years of age. Adult females nest every 2 to 5 years, depositing between 1 and 3 clutches comprised of 100-115 eggs.
As adults these turtles are herbivorous and routinely feed on sea grasses (Thalassia testudinum). Green turtles are keystone species within their range and play a vital role in the proper function of the seagrass ecosystem.
Greens prefer the Caribbean side of the island for nesting but occasionally nest on the Atlantic side of the island each year. Greens primarily nest on St. Kitts from July through February; however, sporadic nesting can occur year round. Foraging greens can be seen year round in the near shore waters.