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Scientific Name: Eretmochelys imbricata
Category: Sea Turtles
Hawksbill Turtles live in all of the earth's oceans, but are found mainly in the Indian, Pacific and Atlantic Oceans. The turtles live near the shore in caves and on ledges in bays, estuaries, and lagoons. In these places they feed on sea sponges, their favorite food. Since sponges live mostly in tropical waters, Hawksbill Turtles are also found in tropical waters. However, they have also been sighted as far north as Long Island Sound on the east coast of North America. Sea sponges are made of silica rather than carbon and are most commonly found among coral reefs. When other animals, including other turtles eat toxic varieties of sponges they get very sick and die, but the Hawksbill Turtle can eat these sponges with no ill effects. The toxic chemicals from the sponges accumulate in the turtles bodies and many animals that try to eat the turtles get sick and die. Crocodiles, octopuses, sharks and some large fish can eat the turtles and are not affected by the toxic chemicals. The turtles also eat jellyfish and comb jellies.
The Hawksbill Turtle usually grows to be a meter (3.3 feet) in length and can weigh up to 80 kilograms (176 lb). They look similar in appearance to other sea turtles, but you can tell the difference because the Hawksbills head has a sharp beak that is curved. They also have a sharp edge along the rear of their shell. It is their distinctive shell that has long made it attractive to sailors and people in the jewelry trade. The shell has black and light brown lines across an amber background. Their flippers have two claws to help pull the sea sponges off the reefs. The head is long and tapers to a point, while the lower jaw is V-shaped. These distinctive head features give the Hawksbill Turtle a bird-like appearance.
These turtles mate from April to November in the Atlantic Ocean and from September to February in the Indian Ocean. Mating takes place in the shallow waters off their nesting beaches. In the Pacific, the major nesting beaches are found from Baja California south to Costa Rica and Nicaragua. In the Atlantic, they nest all around the Caribbean and in the Indian Ocean they nest along the coast of India and the eastern coast of Africa. Females then crawl out of the water onto the beaches to dig a nest in the sand and lay their eggs. There are usually about 140 eggs per nest. The mothers then cover the eggs with sand to hide them from predators before returning to the sea. This is the only time that Hawksbill Turtles come ashore during their lifecycle. Female turtles may lay eggs as many as 4-5 times a year. The females nest only every 2-3 years. As with many other sea turtles, the sex of the hatchlings is dependent on the temperature of the water during incubation. The largest nesting beaches are in Australia and along the Great Barrier Reef.
It takes about two months for the eggs to hatch. The hatchlings generally weigh about 24 grams (~.85 oz.), are about 25.4 mm (~1 inch) long, and have dark shells. After hatching, they move to the ocean at night, following the moonlight that is reflected off the water. They must reach the water before daylight in order to be safe. Those still on the beach then become prey for seabirds and crabs. After they enter the water, the hatchlings live along the sea floor near the shore and commonly hide in the seaweed and human trash like Styrofoam and plastic debris that collects there. The hatchlings also eat this trash and get sick. When the Hawksbill hatchlings have reached about 25 cm (~10 inches) in length, they migrate out to live in the coral reefs. Hawksbill Turtles typically live for 30-35 years and outside of the mating season, they live alone.
The Hawksbill Turtle is on the critically endangered species list and may soon go extinct. The turtles are often part of the by-catch in fisherman's nets. The development of the TEDS (turtle excluder devices) now used by fishermen has reduced the number of turtles caught in these nets. Since the turtle life-cycle is so closely associated with coral reefs, their numbers are decreasing with the dying off of these reefs world-wide. It is illegal to catch these turtles or to sell their shells. Although these activities are illegal in many countries, the laws are not necessarily enforced. Selling turtle meat and their shells is still common in the Caribbean. In the past, especially in Asia, these turtles were captured and their shells were used to make tortoise shell ornaments, jewelry, and other decorative items. The Greeks and Romans also used their shells for jewelry and combs. Other parts of these turtles are used in cosmetics, oil and perfume, and the meat of the Hawksbill Turtle is a delicacy in many countries, especially in China. Brazil and Venezuela have pictures of the Hawksbill Turtle on their paper money.
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