Leatherback sea turtles do not usually nest in Kenya, however this female emerged on our nesting beach!
The leatherback turtle has the largest distribution of all sea turtles and are found as far North as Canada and as far south as South America. They are largest turtles on Earth reaching up to 2.5m in carapace length, nowadays they tend to average at 1.5m carapace length.
All sea turtles have a hard keratin carapace to protect themselves, except the leatherback turtle. The leatherback has 7 boney keels or ridges running down its cartilaginous back covered with a thick black leathery skin with white spots. These keels help to make the leatherback hydrodynamic in the water, making it the fastest sea turtle in the ocean.
Leatherbacks can dive to as deep as whales, as far as 1200m, much deeper than any other sea turtle. They can hold their breath for over an hour. Another adaptation this species exhibits that other species of turtle do not is that they are able to maintain a warm body temperature in cold water. They do this using their large body size, changes in swimming activity and blood flow, and a thick layer of fat. They also migrate further than any species of sea turtle to travel between their breeding and feeding grounds, averaging 6,000km each way.
They are renowned to feed primarily on jellyfish, but they also consume other soft-bodied animals such as tunicates. Scientists suggest that to sustain an animal of its size, they would have to consume up to 1000 jellyfish per day. With the rapid decline of leatherbacks worldwide, a high influx of jellyfish has been documented.
Leatherbacks lay approximately 80 eggs in each nest, including a layer of infertile eggs on the top as a way of protecting the nest from predators; they will have their fill of the infertile eggs and hopefully leave the fertile eggs still in the nest. In one season a single female may come up to nest 10 times!
Some populations of leatherback seem to be stable but others, e.g. the Pacific population is currently declining at an unsustainable rate, this is due to egg harvest, fishery by-catch, coastal development, amongst others. Some of these Pacific populations have disappeared entirely.