TRUST FOR ENVIRONMENT EDUCATION, CONSERVATION & COMMUNITY DEVELOPMENT

Satellite tagging as a important conservation tool, for nesting Olive Ridley sea turtles on the Chennai Coast

Tamil Nadu with its 980 km coastline has both East (900 km) and west (80 km) coasts. There are wide sandy beaches which are sporadic nesting beaches for the olive ridley sea turtle along Tamil Nadu coast and in particular along the Chennai coast the conservation area. There is an urgent need to protect the ridley nesting sites along the coast and the adult olive ridley turtles en-route to the mass nesting beaches of Orissa. It is also imperative to reduce fishery related mortality to the juvenile hawksbill and green turtles foraging( feeding) in the ocean habitat before the turtle populations collapse. It is difficult to protect the turtles when they are in open ocean, but relatively easy to study them when they come to the near shore waters for mating and nesting. We propose to use satellite telemetry tagging to explain important information of the movements of the Olive Ridley’s. Using satellite tags (Platform Transmitter Terminals) it has been possible all over the world to detail the number of nesting intervals and post-reproductive migration routes of adult females and males, and to ascertain the location and use of foraging grounds in both ne ritic ( near shore) and pelagic( open ocean) areas by adults and juvenile sea turtles. These information also determine critical links in the interesting movements patterns of the Olive Ridleys between India and neighboring countries.

TREE Foundation will tag two olive ridley sea turtles with Satellite Telemetry Tags (Platform Transmitter Terminals) during the 3rd week of February and 1st week of March 2010 nesting season to study the nesting intervals, feeding grounds and migratory route to reduce adult mortality and help conservation of the endangered species. The tagging will be done tentatively on Feb 27th and March 7th. TREE Foundation is running the Community based joint conservation program that with the support form Wildlife Wing of the Forest Department, and Department of Fisheries, Tamil Nadu.

Sea Turtles are among the world’s most migratory animals. They are a pelagic species that indicate the state of the earth’s marine environment. All species of sea turtles are now struggling to survive modern ocean changes. These charismatic and graceful reptiles are facing extinction from pollution, long line fishing, gill nets, and coastal development. One of the specific goals of TREE Foundation’s community based sea turtle conservation program is to empower the present generation with the will and tools to ensure that these ancient mariners continue to swim the globe.

TREE Foundation has obtained permission from the Ministry of Environment and Forest and Chief Wildlife Warden, Tamil Nadu to attach 2 satellite tags on two olive ridley sea turtles on the Chennai coast. The ‘Sirtrack Kiwi Sat 202’ satellite tags have been sponsored by the Whitley Fund for Nature UK, through an Associate Award that Dr Supraja Dharini won in 2009.

The scientific program will be conducted during the 3rd week of February and 1st week of March. Those interested in participating can contact treefoundation2002 @ gmail.com or check www:treefoundationindia.org

Project area

During the past 7 years of the community based sea turtle conservation work undertaken by TREE Foundation, it has observed and recorded that there has been a huge number of adult turtle death. Studies were conducted along 13 km stretch in Chennai coastal area from Periya Neelankarai to Reddy Kuppam, to know if the death casued is due to fishiery related activities. This project will help propose practical suggestions with well documented data for reduction of adult turtle mortality, their migratory patters and their foraging sites and submit mitigation measures through the Department of Fisheries and Wildlife wing of the Forest Department and take necessary action.

Satellite transmitters yield data that could not otherwise be obtained. Gaining an understanding of the movements of marine turtles is far from a simple task: turtles spend most of their life at sea below the surface and tend to migrate long distances among disparate developmental, breeding and adult feeding habitats. For decades the main tool used to gain insights into the distribution and migration in sea turtles was flipper tagging, with important insights gained. However, recent technical advancements and the use of satellite transmitters have greatly increased our knowledge of marine turtle migrations.

Essentially these are radio transmitters that transmit a signal that can be detected by polar orbiting satellites. Depending largely on the number of signals received from an individual tag by a satellite in any given overpass, locations with different levels of accuracy can be assigned. In addition to generating positional information, other data from onboard sensors can also be transmitted, giving information of a range of parameters such as temperature, depth and dive profiles as well as swim speed.

Because transmitters can be attached to turtles and the data collected can be recovered by satellite even if the turtle swims hundreds or thousands of kilometers away from where it was released, the technique holds great potential for unlocking many secrets of marine turtle behavior and ecology. At the current time, all satellite tags that are commercially available function through the ARGOS system.

What are satellite tags and how do they work?

Essentially these are radio transmitters with GPS that transmit a signal that that can be detected by polar orbiting satellites. Depending largely on the number of signals received from an individual tag by a satellite in any given overpass, locations with different levels of accuracy can be assigned. In addition to generating positional information, other data from onboard sensors can also be transmitted, giving information of a range of parameters such as temperature, depth and dive profiles as well as swim speed. Because transmitters can be attached to turtles and the data collected can be recovered by satellite even if the turtle swims hundreds or thousands of kilometers away from where it was released, the technique holds great potential for unlocking many secrets of marine turtle behavior and ecology. These are important tools for spreading awareness to a wide range of people.

The outcome of the study will be shared with the Ministry of Environment and Forest and Fisheries.

Loggerhead tagged at Gabon