Sea Turtles Of The Indian Ocean

Six of the world’s seven species of sea turtles live in the Indian Ocean: the flatback, green, hawksbill, leatherback, loggerhead and olive ridley.  The abundance of each species differs between countries and oceanic areas. While green turtles and hawksbills are abundant in shallow coastal areas, such as in the Maldives and Kenya, the olive ridley turtle occupies more oceanic habitats, migrating towards coastal areas for nesting.

Important Nesting Grounds

Nesting beach on Gaadhoo Island in the Maldives. Image.
Nesting beach on Gaadhoo Island in the Maldives, a green turtle hot spot. © Leanna Crowley.

The Indian Ocean is home to countless sea turtle nesting sites, particularly for those of the olive ridley turtle. Just a handful of mass nesting beaches in the Indian Ocean account for the majority of olive ridley nesting within the region. Three arribada beaches in Odisha, India make up for an estimated 100,000+ nests per year: Gahirmatha, Devi River mouth and Rushikulya.

Other important nesting sites in the Indian Ocean include that of the critically endangered hawksbill. Hawksbills can be found nesting in the Seychelles, Indonesia, Australia and Oman. Considering many populations of hawksbill have been severely depleted, these nesting hotspots are extremely valuable for the future of this species.

Despite leatherback turtles being less common in the Indian Ocean than most other sea turtle species, they do have important nesting grounds in Indonesia, South Africa, Sri Lanka, Mozambique and the Andaman and Nicobar Islands. Meanwhile, the enigmatic flatback turtle predominantly resides in Australian waters, with Crab Island (Queensland, Australia) hosting the largest nesting population.

As well as this, several tens of thousands of female loggerhead turtles can be found nesting around the islands of Masirah (Oman) and Socotra (Yemen), making this population the second largest nesting aggregation of loggerheads in the world!

Epic Migrations

A green turtle swimming in the blue.

Green turtles have recently been recorded migrating just under 4,000km annually within the Indian Ocean, with one individual turtle travelling from Chagos Islands in the Indian Ocean to the coast of Somalia in east Africa!

Like many other species of sea turtle, green turtles frequently migrate between foraging and nesting sites. Nesting sites from green turtles within the region include the Seychelles, Maldives and Oman.

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References:

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