Kurma mela: Olive Ridley turtle mass nesting science

• The Olive Ridley turtle, a vulnerable sea turtle species, has seen a record-breaking seven lakh turtles nesting at Odisha’s Rushikulya beach in March.

• The turtles are known for their synchronised mass nesting events called arribada, meaning “arrival.”

• The IUCN Red List estimates that the number of Olive Ridleys worldwide has dropped by 30-50% since 1960.

• The turtles’ primary nesting sites are along the Pacific coasts of Mexico and Central America, with Odisha being a critical location.

• Research shows that Olive Ridley turtles that hatch at a nesting site are “imprinted” with a map of the local magnetic field, which they return with remarkable precision to the site by following this map.

• Other ecological factors that affect their choice of nesting sites include salinity, land slope, risk of predation, and rainfall.

• As turtle populations swell, beaches often become battlegrounds, with a population that arrives after another has already nested at a beach digging up existing nests and breaking the eggs.

• The sex ratio of hatchlings in sea turtles is determined by temperature, with rising temperatures shifting the sex ratio more towards females.

• For a sea turtle population to thrive, it needs strays and wanderers like these turtles, which establish new places for the arribada.

• Modern conservation efforts, such as artificially incubating eggs and protecting beaches, have helped boost turtle populations, but the question arises whether these measures will be too successful.

• Turtle tourism has surged in recent years, raising awareness but also stressing these gentle creatures.

• The priority is to ensure the longevity of these nesting beaches and balance tourism with ethical responsibility.