BackgroundBackground

Background

Marine turtles arose from an ancient lineage of terrestrial reptiles, developing paddle-like limbs as they adapted to life in the oceans. As a consequence of this lineage, marine turtle females must return to land periodically to lay their eggs in beach foreshores. When hatchlings emerge from their nests they orient to the low light of the horizon and head towards it unless distracted by other lights. Once in the water they will swim at 90° to the wave fronts until clear of the inshore waters. Generally hatchling turtles disappear into oceanic currents and gyres where they will stay until large enough to move out into developmental habitats. There they continue to feed and grow within waters that may well be in another nation’s jurisdiction. The exceptions are the flatback turtle, which spends most of its life within the continental waters of Australia, and the leatherback turtle, which spends most of its life in the open ocean.

A marine turtle may take up to 30–50 years to mature. Adults do not breed every year. In a breeding year they migrate over long distances between feeding and nesting grounds and nest a number of times. During the nesting season a female will not normally feed until after the final clutch is laid and she begins the return migration to the feeding grounds. These life history characteristics make marine turtles vulnerable to a range of influences that can affect the integrity of their populations and populations in the wild. A detailed description of each species’ ecology in Australia can be found in http://www.ea.gov.au/coasts/species/turtles/index.html

Historically, only indigenous Australians took Australian marine turtles and their eggs, but post World War II Australia established itself industrially, and the economy grew. Marine turtles, particularly the hawksbill and green turtles, were subject to unsustainable harvests for soup, meat or shell until 1971. Increased exploitation of other commercial fish species also resulted in increased bycatch of species including marine turtles. The expanding

Australian population and economy has also exposed marine turtles to increasing mortality through marine debris, boat strike in waters popular for recreational boating, habitat loss, predation of eggs by feral animals, noise, oil pollution, and the continuing harvest in Australia.

Marine turtles’ life history traits mean that any high annual take of animals will result in a significant population decline, and historically, they are thought to have undergone a steady and significant decline in Australian waters. This plan seeks to promote cooperative activities within sectors of the community that can reduce impacts on marine turtles and enhance the survival of marine turtles in the wild.