Interesting Creatures… Kemp's Ridley Sea Turtle (Lepidochelys kempii )

Interesting Creatures… Kemp’s Ridley Sea Turtle (Lepidochelys kempii )

Dec 23, 2018 Features / Columnists, Interesting Creatures in Guyana

Kemp’s ridley sea turtle (Lepidochelys kempii ), or the Atlantic ridley sea turtle, is the rarest species of sea turtle and is critically endangered. It is one of two living species in the genus Lepidochelys (the other one being L. olivacea, the olive ridley sea turtle).
Kemp’s ridley is a small sea turtle species, reaching maturity at 58–70 cm (23–28 in) carapace length and weighing only 36–45 kg (79–99 lb). Typical of sea turtles, it has a dorsoventrally depressed body with specially adapted flipper-like front limbs and a beak.
The adult Kemp’s ridley has an oval carapace that is almost as wide as it is long and is usually olive-gray in colour. The carapace has five pairs of costal scutes. In each bridge adjoining the plastron to the carapace, there are four inframarginal scutes, each of which is perforated by a pore. The head has two pairs of prefrontal scales. Hatchlings are black on both sides.
The Kemp’s ridley has a triangular-shaped head with a somewhat hooked beak with large crushing surfaces. This turtle is a shallow water benthic feeder with a diet consisting primarily of mollusks, crustaceans, jellyfish, fish, algae or seaweed, and sea urchins.
Juvenile turtles tend to live in floating sargassum seaweed beds for their first years. These turtles change colour as they mature. As hatchlings, they are almost entirely a dark grey-black, but mature adults have a yellow-green or white plastron and a grey-green carapace. They reach sexual maturity at the age of 10-12.
The nesting season for these turtles is April to August. They mate offshore. Gravid females land in groups on beaches in what is commonly called an arribada or mass nesting. They prefer areas with dunes or, secondarily, swamps. The estimated number of nesting females in 1947 was 89,000, but shrank to an estimated 7,702 by 1985.
Females nest 2-3 times during a season, keeping 10 to 28 days between nestings. Incubation takes 45 to 70 days. There are, on average, around 110 eggs in a clutch. The hatchlings’ sex is decided by the temperature in the area during incubation. If the temperature is below 29.5°C, the offspring will be mainly male.
These turtles are called Kemp’s ridley because Richard Moore Kemp (1825-1908) of Key West was the first to send a specimen to Samuel Garman at Harvard. However, the etymology of the name “ridley” itself is unknown. Prior to the term being popularly used (for both species in the genus), L. kempii at least was known as the “turtle”.
At least one source also refers to the Kemp’s ridley as a “heartbreak turtle”. In her book The Great Ridley Rescue, Pamela Philips claimed the name was coined by fishermen who witnessed the turtles dying after being “turned turtle” (on their backs). The fishermen said the turtles “died of a broken heart”.
Hunting first depleted their numbers, but today major threats include habitat loss, pollution, and entanglement in shrimping nets.
One mechanism used to protect turtles from fishing nets is the turtle excluder device. Because the biggest danger to the population of Kemp’s ridley sea turtles is shrimp trawls, the device is attached to the shrimp trawl. It is a grid of bars with an opening at the top or bottom, fitted into the neck of the shrimp trawl. It allows small animals to slip through the bars and be caught while larger animals, such as sea turtles, strike the bars and are ejected, thus avoiding possible drowning. [Source: Wikipedia]