What is a loggerhead turtle? The loggerhead turtle (Caretta caretta) is the most endangered turtle that nests in Australia. Human activities are the main cause of its decline. They may be drowned in fishing nets, strangled by rubbish, hit by boats or killed for meat and leather, and their eggs are taken for food and aphrodisiacs.
What does it look like? Most loggerhead turtles are less than a metre long and rarely weigh more than 150 kilograms. Older adults can develop very large heads. The shell is more or less heart-shaped, and quite elongated. It is usually dark brown above and much lighter below.
Where does it live? Loggerhead turtles live mostly in warm shallow seas and estuaries. They mate and nest in tropical and subtropical areas including those in WA. It is estimated that 1500 to 2000 females nest annually in WA, predominantly in the Shark Bay Marine Park, Ningaloo Marine Park and Muiron Islands Marine Management Area. A few also nest in the proposed Dampier Archipelago Marine Park.
What it eats and how: Feeding in estuaries and along the continental shelf, loggerheads use the strong jaw muscles in their large heads to crush shellfish, crabs, sea urchins and jellyfish.
Threats: It is thought that longline fisheries drown many loggerheads, which take baited hooks. Loggerhead turtles are also threatened by introduced foxes digging up and eating the eggs, especially in the coast adjacent to Ningaloo Marine Park, so the Department of Environment and Conservation (DEC) undertakes fox control in the area. Any increase in air and sea temperatures due to global warming could affect loggerhead turtles by biasing the sex ratios of hatchlings (the sex of the hatchlings is influenced by the temperature of the nest).
Breeding: They begin to breed round about October. Individual females only nest every two to five years but lay up to five clutches per nesting season. Each clutch contains 100 to 150 parchment-shelled eggs. When the young hatch from late December to early April they immediately have to find their own way to the ocean and fend for themselves. In the winter months, baby loggerhead turtles are often carried south from northern breeding areas by means of the Leeuwin Current. The youngsters usually have a shell length of between five and eight centimetres and are blown onto beaches between Perth and the South Coast in storms.
Behaviour: Loggerhead turtles that live in WA waters migrate from feeding grounds in northern WA, the Northern Territory and probably Indonesia to breeding areas further south such as those adjacent to the Shark Bay Marine Park.
Conservation status: The loggerhead turtle is fully protected in Australian waters. It is listed as endangered.
How you can protect the loggerhead turtle: Never throw plastic bags and other rubbish in the water, as turtles may accidentally eat them and die. If you find a turtle with a tag, write down the number and contact the Department of Environment and Conservation (DEC), which conducts turtle tagging with the help of numerous volunteers at important nesting beaches in northern WA. The information that his collected is used to better manage and protect WA's populations of loggerhead turtles. If you find a dead turtle you should also tell DEC.
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