Environment and Resource Management

Pacific ridley turtle (olive ridley)


Hatchling. ©Dr M. Guinea

Common name: Pacific ridley, Olive ridley turtle

Scientific name: Lepidochelys olivacea

Conservation status: The Pacific ridley turtle is 'Endangered' in Queensland (Nature Conservation Act 1992) and 'Endangered' nationally (Environment Protection and Biodiversity Conservation Act 1999).

Description: Pacific ridleys are grey or olive-grey above, usually without any conspicuous markings and whitish below. Their head is large and massive. The carapace (shell) is broad and heart-shaped, usually with six or more costal scales. They can grow to a total length of 1.5 metres. Their hatchlings are blackish above, dark brown below.

Habitat and distribution: Pacific ridleys occur in shallow, protected waters, especially in soft-bottomed habitats. They are pantropical in distribution but rarely found around oceanic islands. Major breeding aggregations occur in Mexico, the west coast of Costa Rica, in Surinam, and the east coast of India. In Australia, they occur along the coast from southern Queensland and the Great Barrier Reef, northwards to Torres Strait, the Gulf of Papua, Gulf of Carpentaria, Arafura Sea and Joseph Bonaparte Gulf in Western Australia. Low density nesting has been recorded at a limited number of sites over recent decades. Within Queensland, breeding is known only from isolated nestings at five locations within the Gulf of Carpentaria: Crab Island, Edward River, north of Weipa, Scrutten River mouth and the Wellesley Islands.

Behaviour and life history: No large rookeries of Pacific ridleys have been recorded in Australia. Pacific ridleys nest all year round, although most nesting occurs during the dry season from April to November. Females lay on average about 109 large round, parchment-shelled eggs. Hatchlings emerge from the nests about two months after laying.


Sub-adult. ©Col Limpus

Threatening processes: All marine turtle species are experiencing serious threats to their survival. The main threats are pollution and changes to important turtle habitats, especially coral reefs, seagrass beds, mangrove forests and nesting beaches. Other threats include accidental drowning in fishing gear and, over-harvesting of turtles and eggs.

Recovery actions:

What can be done to help this species?
You can help this species by:

Further information:
Turtle watching

Department of the Environment and Heritage. 2005. Protected marine species identification guide (PDF)* . Department of the Environment and Heritage, Canberra.

Environment Australia and Marine Turtle Recovery Team 2003. Recovery plan for marine turtles in Australia. Department of Environment and Heritage, Canberra.

Department of the Environment and Heritage 2005. Protected marine species identification guide (PDF)*. Department of the Environment and Heritage, Canberra.

Carpentaria Ghost Net Programme

* Requires Acrobat Reader

Last updated: 05 October 2007

Animals

Topics in this site