Olive ridley turtles are best known for their behavior of synchronized nesting in mass numbers, termed arribadas.
Females return to the same beach from where they hatched, to lay their eggs.
They lay their eggs in conical nests about one and a half feet deep, which they laboriously dig with their hind flippers.
In the Indian Ocean, the majority of olive ridleys nest in two or three large groups near Gahirmatha in Odisha.
The coast of Odisha in India is one the largest mass nesting site for the olive ridley, along with the coasts of Mexico and Costa Rica.
In 1991, over 600,000 turtles nested along the coast of Odisha in one week.
Nesting occurs elsewhere along the Coromandel Coast and Sri Lanka, but in scattered locations.
However, olive ridleys are considered a rarity in most areas of the Indian Ocean.

They are also rare in the western and central Pacific, with known arribadas occurring only within the tropical eastern Pacific, in Central America and Mexico.
In Costa Rica, they occur at Nancite and Ostional beaches.
Two active arribadas are in Nicaragua, Chacocente and La Flor, with a small nesting ground in Pacific Panama.
Historically, several arribadas were in Mexico, Playa Escobilla and Morro Ayuda in Oaxaca, and Ixtapilla in Michoacan are the three arribada beaches in the present .

Although olive ridleys are famed for their arribadas, many of the nesting grounds can only support relatively small to moderate-sized aggregations (about 1,000 nesting females).
The overall contribution and importance of these nesting beaches to the population may be underestimated by the scientific community.
Olive ridley turtles are best known for their behavior of synchronized nesting in mass numbers, termed arribadas. Females return to the same beach from where they hatched, to lay their eggs. They lay their eggs in conical nests about one and a half feet deep, which they laboriously dig with their hind flippers. In the Indian Ocean, the majority of olive ridleys nest in two or three large groups near Gahirmatha in Odisha. The coast of Odisha in India is one the largest mass nesting site for the olive ridley, along with the coasts of Mexico and Costa Rica. In 1991, over 600,000 turtles nested along the coast of Odisha in one week. Nesting occurs elsewhere along the Coromandel Coast and Sri Lanka, but in scattered locations. However, olive ridleys are considered a rarity in most areas of the Indian Ocean.
They are also rare in the western and central Pacific, with known arribadas occurring only within the tropical eastern Pacific, in Central America and Mexico. In Costa Rica, they occur at Nancite and Ostional beaches. Two active arribadas are in Nicaragua, Chacocente and La Flor, with a small nesting ground in Pacific Panama. Historically, several arribadas were in Mexico, Playa Escobilla and Morro Ayuda in Oaxaca, and Ixtapilla in Michoacan are the three arribada beaches in the present .
Although olive ridleys are famed for their arribadas, many of the nesting grounds can only support relatively small to moderate-sized aggregations (about 1,000 nesting females). The overall contribution and importance of these nesting beaches to the population may be underestimated by the scientific community.
Olive ridley sea turtle