Olive Ridley turtles are back on Mangaluru beaches! 

The coast of Karnataka has the distinction of being an Olive Ridley rookery on India’s western coast but some beaches around Mangaluru division in the southern state didn’t see Olive Ridley nesting sites since 1985 due to environmental factors like increased salinity and beach pollution due to human activity. 

This changed on February 5, 2024 when around 12 nesting sites were identified on Tannirbhavi and Sasihithlu beaches in coastal Karnataka. “Each site should have closer to 150 eggs as per the typical nesting habits of the Olive Ridley turtles. There are two beaches, Sasihithlu and Tannerbavi, on which the turtles have nested. This was the first incident of nesting after a hiatus of 29 years (since 1985), which has been a pleasant development,” said V Karikalan, chief conservator of forests, Mangaluru wildlife division. 

On the other two beaches, Kundapur and Byndoor, the nesting sites have been more or less stable and recorded 200 nesting sites a year. 

Speaking to Down To Earth, Karikalan said, “The Olive Ridley turtles are Schedule 1 animals under the Wildlife Act of 1972 and carry equal importance as tigers and elephants. The species coming back for nesting on Tannirbhavi and Sasihithlu beaches after such a long time is a significant development.”

He added: 

This means vital changes are happening on these beaches. First, the beaches are pollution-free and not subject to much human activity, and secondly, the Olive Ridleys have found these beaches a haven for their progeny.

The turtles are extremely sensitive to human activity and have chosen to nest only in the uninhabited parts of the Tannirbhavi and Sasihithlu, according to experts from the Karnataka Veterinary, Animal, Fisheries and Animal Sciences University, Fisheries College, Mangaluru.

The development has also ushered in a series of conservation activities. The local fisherfolk have offered their help to conserve the eggs and protect them from predators like dogs, birds and jackals that frequent these beaches. Chandra Bangera, a youth leader, has brought together youths from three nearby fishing villages to take up night patrolling on these beaches along with the forest officials. “Information has also been sent to the police about the developments, including the night patrolling on the beaches,” he added.

The forest department has created a ‘clipper movement’ on the sites by barricading each of the 12 nesting sites. “These 12 sites will be guarded day and night for the next 40 days till the hatchlings reach safely into the sea,” said Vasanth Bangera, a senior fisherman who vividly remembered the last nesting season in 1985. “We had taken the same care in 1985 with the local youth back then, and I remember counting not less than 600 hatchlings that reached the sea from the beach.”

Eggs laid by nesting turtles at Tannirbhavi beach near Mangaluru. Photo: Author provided

Olive Ridley turtles feed on the jellyfish in the sea, said experts from the Karnataka Veterinary, Animal, Fisheries and Animal Sciences University, Fisheries College, Mangaluru. The jellyfish are known for their ability to bring down the fish population in the sea and also inflict injuries to the fisherfolk, they added. The revival of nesting at the southernmost point of the Arabian Sea in Karnataka, at least 130 kilometres away from the thriving sites in Kundapur and Byndoor, is a matter for research, the experts opined. 

“I have inspected the sites on Tannirbhavi Beach. In terms of environmental development, it is a significant event, and I have already asked the forest officials to protect the eggs and keep the mortality under check. The fisherfolk who are assisting the forest department in conserving the eggs must be given incentives and sensitised about similar events in the future,” the forest minister of Karnataka, Eshwar Khandre, told DTE.

The number of turtles that arrive on the beaches of Karnataka is not greater than the Gahirmatha beach in the Kendrapara district of Odisha but after they revived their presence in southern Karnataka, the numbers might slightly be more than those beaches if not on par, according to conservation activists.

They generally arrive by night and leave by daybreak after laying eggs. The eggs hatch after a minimum of 10-12 days. 

Degradation of nesting beaches, ongoing directed harvest and by-catch in fisheries have all contributed to the species’ decline, experts noted. Over the past five years, the nestling periods at Kundapur have become considerably shorter and their numbers arriving on the Karnataka coast (only at Maravanthe) have declined. There are reports that they used to come in larger numbers.

The decline in the turtle population has initiated many conservation efforts, but none on the western front, conservationists complained. On the eastern coast at Nagapattinam and at three locations in Odisha, including Gopalpur and Gahirmatha, a lot more regulation is required to prevent rampant poaching of the Olive Ridleys, they added.

Why conserve Olive Ridleys?

The Olive Ridley turtles are listed as endangered in the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. They may be the most abundant sea turtle on the planet, but they are also stated to be the most exploited, highlighted conservation specialists. 

In India, the mortality rate may not be grave but it is important to ascertain that hatchlings naturally go into the sea, adults are not poached for food, and their eggs are not devoured by the wild animals, they added.

There has been a 50 per cent reduction in the Olive Ridley population size since the 1960s, the experts highlighted, quoting the Marine Turtle Specialist Group of the IUCN. Although some nesting populations have increased in the past few years, the overall reduction has been greater than the overall increase.

The Kundapur Wildlife Division has collected a treasure trove of information on why the ‘season of laying eggs’ (arribada, as it is called by the scientific community) occurs in certain places all over the world. The natural elements that trigger arribada include offshore winds, lunar cycles, the release of pheromones by females and the temperature of the seawater that drives the Olive Ridley turtles to certain sea coasts in the world, reports showed.

“There is lots of work. We have to gather the volunteers to chase away the stray dogs in the daytime and foxes in the night time, and human predators have to be warded off,” said Dasi Kharvi, a lead volunteer of the Maravanthe Turtle Conservation Initiative, Kharvi. The other 45 people from the nearby villages have already had two sittings in the tea shop on the beach and their resolve to protect the Olive Ridley turtles appears to have grown stronger, Kharvi added.

“Last year, despite our best efforts, we found many hatchlings of the turtles being sold in the market as pets, nests ravaged by wild animals and adult turtles slain by humans for consumption,” Kharvi shared.