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• Download the fact sheet as a PDF file
• About the fact sheet
• Feral pigs: a major threat!

About the fact sheet

What does it look like?

The Flatback Turtle gets its name from its relatively flat, smooth shell - other marine turtles have a high domed shell. Flatback shells are wide with turned-up edges, covered by a thin fleshy skin and measure up to 1 metre long at adulthood. The colour is usually yellow-grey or olive-grey, with the underside a pale yellow. Flatbacks are a medium-sized marine turtle and can weigh up to 90 kilograms.

Hatchlings are olive-green with scutes (the plates on the shell) outlined in black. When they emerge they are usually larger than other marine turtle hatchlings and weigh around 43grams.

Where does it live?

All recorded nesting beaches for Flatback Turtles occur in Australia. The turtles are unique in many ways including their choice of habitat. Although they do occur in open seas, they prefer inshore waters and bays where their feeding ground is the shallow, soft-bottomed seabed. They feed in northern coastal areas, from Western Australia's Kimberley region to the Torres Strait extending as far south as the Tropic of Capricorn. Feeding grounds also extend to the Indonesian Archipelago and the Papua New Guinea Coast.

Flatbacks have the smallest migratory range of any marine turtle species, though they do make long reproductive migrations of up to 1300 kilometres. This restricted range means that the Flatback is vulnerable to habitat loss, especially breeding sites.

While in the sea the turtles spend much of their time at the surface basking in the sun.

What do they eat?

The Flatback is carnivorous, feeding mostly on soft-bodied prey such as sea cucumbers, soft corals, jellyfish, molluscs and prawns.

Did you know...

This species breeds and nests only in Australia. It lays approximately 50 eggs per nest, the fewest of any marine turtle, but the eggs are quite large compared to the species' body size.

Flatback Turtles nest on tropical beaches and offshore islands in Western Australia, the Northern Territory, the Gulf of Carpentaria and all the way round to Mon Repos, in Queensland. Nesting season usually occurs between November and January, but in the Northern Territory it can be all year round with a peak season in August.

Feral pigs: a major threat!

Why are feral pigs a problem in Australia?

Pigs (Sus scrofa) were first brought to Australia by Europeans as a food source, and were transported around the country by settlers during the 19th century. Some pigs inevitably escaped or were allowed to wander and eventually formed feral colonies. Today there are between 13 million and 23 million feral pigs in Australia, found in every state except Tasmania. Some pig hunters have been known to deliberately release pigs in rural areas, which has contributed to the increase in pig distribution since the 1970s.

Feral pigs have an impact on at least 18 threatened species, including the Flatback Turtle. As well as competing with native species for food, they are active predators of many native birds, reptiles, mammals and invertebrates. Their digging and wallowing can damage or destroy plants, reduce regeneration and alter soil structure, water flows and plant composition.

Why are they a threat to Flatback Turtles?

Many animals, both native and introduced, prey on marine turtle eggs and hatchlings. Pigs have an excellent sense of smell and can easily find buried turtle eggs and dig them out of the sand. In particular feral pigs are responsible for high levels of Flatback Turtle nest predation on Cape York Peninsula beaches. Other threats to eggs and hatchlings include vehicles driving over nests, light pollution and human disturbance on nesting beaches.

Flatback and other marine turtles face a huge range of threats, including being caught as 'bycatch' in commercial fishing operations, getting tangled in discarded ('ghost') fishing nets and ingestion of marine debris.

What's being done?

The Australian Government has listed 'Predation, habitat loss, competition and disease transmission by feral pigs' as a Key Threatening Process under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999. A Key Threatening Process is any process that threatens or may threaten the survival, abundance or evolutionary development of a native species or ecological community. The next step is to draft a Threat Abatement Plan to provide for research, management and any other activities to reduce the impact of the process. The Australian Government has worked with the states and territories to prepare a plan tackling the national problem of feral pig impacts.

WWF-Australia and the Lianthawirrayarra Sea Rangers have used satellite transmitters to track Flatback Turtles to learn more about their movements, habitat use and behaviour. The study will help determine which areas are important to the species and what types of threats are likely to impact on them in these areas. A range of other programs are being conducted around Australia to monitor key populations and their threats and to educate the community about the species, in regions including Mon Repos (QLD), Gladstone (QLD), Mapoon (QLD), Sir Edward Pellew Islands (NT), Bare Sand Island (NT) and the Pilbara (WA).

How you can help

• If you have a feral pig problem in your area, contact your state or territory government agency for information about the most appropriate control technique.
• You can help reduce other threats to marine turtles. For example:
  • Make sure no nets, equipment or rubbish is lost overboard when fishing or boating
  • Be aware of turtles in the water and avoid excessive boat speeds that may result in turtle injuries
  • Don't drive on known nesting beaches. If you are on or near a nesting beach at night, check sources of light pollution and where possible cover lights. Be careful not to disturb nesting turtles especially as they are coming up the beach, as this may prevent them from laying eggs
  • Contact your state or territory government conservation agency if you find a stranded, injured or entangled turtle.

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