Sea turtles, a globally endangered species, have been around since even before dinosaurs roamed the earth. They survived both the frigid and the scorching climatic extremes 64 to 66 million years ago that caused the extinction of around seventy per cent of all plants and animals including dinosaurs. Their body design could withstand these events and their form has remained more or less the same. They are one of the earth’s oldest group of animals today. Indian coastal waters are home to five of the seven species of sea turtles - the Hawksbill (Eretmochelys imbricata), Green (Chelonia mydas), Loggerhead (Caretta caretta), Leatherback (Dermochelys coriacea) and Olive Ridley (Lepidochelys olivacea).
Sea turtles in general and the Olive Ridley in particular have fascinated biologists since the 1970s. It is most commonly found on the mainland coasts of India while the other types are found mostly around the Andaman and Nicobar Islands. The other mass nesting site of this species is in Pacific Central America. The term ‘arribada’ was first coined in Mexico to describe the peculiar mass-mating phenomenon of these turtles. The turtles travel thousands of kilometers to these breeding grounds where they mate and nest simultaneously creating extraordinary visual imagery. After mating off-shore, the females arrive at the beach where they dig holes in the sand to lay eggs. When their hatchlings emerge, they drift off with the tidal waves and migrate to their feeding grounds several thousand kilometers away.
View Rookeries of Orissa in a larger map
More than a hundred thousand Olive Ridley turtles visit the sandy beaches of Orissa for mass nesting every year between December and April. The 480 km coast of Orissa has three rookeries, which are colonies of breeding turtles – Gahirmatha (near the mouth of Brahmani and Baitarni rivers), Devi (100 km downstream of Gahirmatha) and Rushikuliya (320 km downstream of Gahirmatha). However, several accounts reveal that the Olive Ridley that commonly nests along the eastern coast of India is in danger of becoming extinct.
Threat to turtles
Beach erosion and cyclonic storms have reduced the size of the Gahirmatha beach considerably. This has caused problems in mass nesting. The turtles have also been subject to mass mortality because of the introduction of mechanized fishing. They are faced with threats not only in the coast but in the coastal waters also. Casualties take place when these turtles get caught in trawl-fishing nets as incidental catch.
The commercial value of their high-protein eggs as well as their meat came to the fore only during the 1970s. Local consumption of sea turtle eggs or meat is negligible but fishermen from Kolkata catch these turtles as this meat is relished in West Bengal. It is estimated that fifty thousand turtles are taken every year to Kolkata. The illumination along the coastline, the establishment of a missile test range, the construction of the Dhamra port near Gahirmatha and the setting up of chemical industries near Rushikulya have created a lot of disturbance for the Olive Ridley sea turtles.
The threat to the population of sea turtles has led to a spate of research in the last three to four decades. This includes genetic studies, monitoring of their nesting beaches, quantifying the incidental capture and so on. Tagging studies, to track the route taken by turtles are underway in Orissa. Usually these are done using external flipper tags or passive integrated transponders or microchips fitted into their shoulder muscles. These studies suggest the mortality of thousands of Olive Ridley sea turtles in Orissa every year. Data collected by several biologists over the last forty years indicates a reasonably reliable trend in the population of Olive Ridley sea turtles – decrease in the seventies, increase in the eighties, followed by a decline beyond the nineties, which coincided with the high incidental catch under mechanized fishing.
Conservationists versus anthropocentrists
Many a time, basic biological aspects like nesting density in a particular beach are not considered while taking up conservation activities. Much of the conflict among the various groups dealing with sea turtles such as conservationists and port developers is essentially caused by differences in their philosophies. Animal rights activists and conservationists have a biocentric approach, where they uphold that nature has an inherent right to exist. Anthropocentrism on the contrary, stresses more on the utilitarian aspects and states that human beings are the most significant species on the planet. The answer lies somewhere in between in a state of “weak anthropocentrism” according to many.
Partners in conservation
Kartik Shankar of the Centre for Ecological Sciences, Indian Institute of Science, Bangalore has been working on community ecology and biogeography. At a recent public lecture titled “Wagging the Dog: The use and abuse of science in marine conservation in Orissa” at the Nehru Memorial Museum and Library, New Delhi, he provided a semi-personal account of his work on the conservation of Olive Ridley sea turtles.
He talked about how several tens of thousands of Olive Ridley turtles are killed due to mechanized fishing. The chief cause of their mortality is not directed at them; these turtles drown after getting trapped in trawl nets, which aren't meant for them in the first place. They are then discarded by the fishermen. Enforcing a conservation measure like the use of Turtle Excluder Devices (TED) in trawl nets in coastal waters open for fishing can bring down turtle mortality. However, turtles also get caught in gill nets and Turtle Excluder Devices cannot be used with them. While the trade in adult turtle meat has reduced over the years, their habitat is increasingly being degraded by coastal development.
The Dhamra Port, in Bhadrak district of Orissa, set up as a joint venture between Larsen and Toubro and Tata Steel has been operational since February 2010 with an annual capacity of 80 million tones. International organizations like Greenpeace, Wildlife Fund (WWF) and International Union for Conservation of Nature (IUCN) have opposed this on the grounds that it will damage the Bhitarkanika mangroves and threaten the Gahirmatha marine sanctuary, just south of the port where the Olive Ridley turtles nest every year.
Kartik Shankar dissected these conservation actors – including the State, the international organisations and several national and local conservation groups and their “Tata versus Turtle” campaign. He examined how these conservation groups have used science to promote the conservation of sea turtles. He spoke on how all the players (the state, conservationists, corporations, academics, fishers) intentionally or institutionally continued to pursue agendas and strategies that were geared more towards helping themselves regardless of what science said. This has had exactly the opposite effect and did not help conservation in the long run.
Conservation is not really about preservation of species and their habitats but about integrating human beings into ecosystems. Species can be preserved through enforcement but long term conservation is “linked to a single, uncompromisable goal - the improvement of human welfare" Western (1989). The answer lies in community-based conservation, where the desire to conserve comes from within, Shankar says.