Olive Ridley Turtles

Context

Olive Ridley turtles nesting along the Tamil Nadu coast have recently begun migrating toward the Sri Lanka Dome, a relatively lesser-known yet highly productive marine region, drawing attention to its ecological significance in the context of the latest developments.

About Olive Ridley Turtles

1. Olive Ridley Turtle (Lepidochelys olivacea): A marine reptile belonging to the class Reptilia, it is among the smallest sea turtle species, identified by its olive-green to greyish shell and a distinct heart-shaped carapace.
2. Feeding and Behavior:  These turtles are omnivorous and are well known for arribada—a synchronized mass nesting phenomenon where thousands of females come ashore to lay eggs simultaneously. 
3. Migration and Reproduction:
   1. Olive Ridleys undertake long-distance migrations of up to around 9,000 km, travelling from the Pacific Ocean to Indian waters.
   2. They typically nest between December and March, laying eggs 1–3 times per season, with each clutch containing roughly 100 eggs.
4. Key Nesting Locations: The coasts of Gahirmatha and Rushikulya in Odisha rank among the largest nesting grounds globally.
5. Major Threats:
   1. Olive Ridley populations face risks from accidental capture in fishing nets (bycatch), illegal hunting, destruction of nesting habitats, and marine plastic pollution.
   2. Climate change further impacts them by altering nesting conditions and affecting food availability due to rising sea levels and temperatures.
6. Protection Status:
   1. Olive Ridley turtles are granted the highest level of legal protection under Schedule I of the Wildlife Protection Act, 1972.
   2. They are listed as Vulnerable on the IUCN Red List.
   3.  They are included in Appendix I of CITES, which prohibits international trade in the species.

Sri Lanka Dome

1. It is a relatively lesser-known but highly productive marine region in the Indian Ocean, known for supporting rich biodiversity.
2. Formation process: It develops due to seasonal upwelling, where cooler, nutrient-rich waters rise to the surface, leading to plankton blooms that attract diverse marine life such as turtles, fish, whales, and seabirds.
3. Seasonal pattern: This process generally begins in May, peaks around July, and declines by September, after which marine species disperse and begin their return migrations.