KARACHI, Sept 8: A satellite transmitter was installed on a green turtle to monitor its movement pattern at the Sandspit beach early on Friday morning. The transmitter was installed under a project being implemented by the World Wide Fund for Nature in collaboration with the Sindh Wildlife Department and Environment Agency of Abu Dhabi.
The green turtle had come for the egg laying at around 8pm on Thursday night and after it completed around a couple of hours long egg laying process it was tagged by the Sindh wildlife department staff and later brought to the WWF Wetland Centre and there the transmitter was installed on the shell.
The transmitter was installed with the help of adhesives besides putting layers of fiberglass and resin coating so that it did not fall off after the turtle’s return to the sea. The battery life of the transmitter is approximately six months. After the installation of the transmitter, the turtle was released back to the sea early on Friday morning (around 5am).
Installed on the carapace of the green turtle for satellite tracking, the transmitter would help in getting information about its post-nesting migration patterns, its foraging area, the time spent for foraging and the resting distance covered per day.
The transmitter would send out the location data, each time the turtle comes out of the water for breathing, which would be received through ARGOS, a French satellite-based data system. It will also help obtaining the data regarding biological characteristics and general behaviour of the green turtles.
The turtle on which the transmitter was installed on Friday has been named as “Chandni-3". This is the second time that transmitter has been installed on a turtle. Earlier, transmitters were installed on two turtles – Chandni-1 and Chandni-2 – in the year 2001. However, soon after their installation, the United States faced 9/11 tragedy and subsequently US naval ships with very powerful equipment arrived that disrupted satellite related services in the region. The information pouring in from turtles stopped forthwith and it was feared that Chandni-1 and Chandni-2 probably had a collateral damage.
All marine turtle species, including the two green turtles and Olive Ridley turtle that come to the city beaches, are declared endangered globally. Hawkesbay and Sandpit, the sandy beaches of Karachi, are among the 11 beaches of the world where marine turtles come to lay their eggs.
While egg laying activity continues round the year, the peak egg laying season is between August and December during which the marine turtles come to the beaches in large numbers. The mother turtle lay between 80 and 120 eggs in one clutch and could lay eggs up to three times in a season, after which she takes a rest of around four to five years.
The mother turtle drags itself out of the sea and after reaching a dry spot in the beach above the high tide mark makes a couple of feet deep nest and lays the eggs, and after the egg laying covers the nest with sand and returns to the sea, leaving the nest and eggs camouflaged but at the mercy of nature.
There are many predators, including stray dogs and human beings, who dig the nest and take out the eggs, which are said to be more nutritious than the chicken eggs and are in great demand in the Far East. When the eggs are hatched and hatchlings go into the sea many of them are attacked by the aquatic birds, many others are eaten up by bigger predators in the sea.
Owing to these threats, the turtles have a high mortality rate during the first year of their life, which is also called the lost year. The turtle survival rate is only 0.1 per cent as only one out of a 1,000 eggs laid grows to be an adult.
Almost all body parts of the turtle are used like its skin is used to make shoes, purses etc, shell is used to make decoration pieces, while turtle soup is a delicacy in the Far Eastern countries. Owing to these threats, all turtle species are declared as endangered internationally and are also protected under the Sindh Wildlife Protection Act.
Under a project initiated a couple of decades back, the Sindh Wildlife Department staff patrolling at the beach collects the eggs from the nests and brings these to protective enclosures. When the eggs are hatched, the hatchlings are released at the beach some distance away from the sea so that they could recognize the beach and return to it for laying eggs after maturing.
The mother turtles are tagged by the wildlife staff and a record is made to see if they return to the beach. In over a couple of decades, it has been observed that the tagged turtles generally return to the same beaches. Only three tagged turtles have been reported from Iran, India and Africa showing that they remain in the same area and rarely travel long distances. Now with the installation of satellite transmitters the scientists would get an accurate pattern of the turtles’ movement.