THE STUDY OFFERED BY :
The Wildlife Institute Of India, Dehradun.

FUNDING AUTHORITY :
GOI-UNDP

DURATION :
One Year

INTRODUCTION

Five of the seven species of sea turtles found world-wide occur in Indian coastal waters. The Olive Ridley turtles (Lepidochelys olivacea) is known to nest in large numbers in the eastern coast of India. In eastern India, Olive Ridley turtles visit the coasts from November till first week of April. The Olive Ridley migrates from the Indian Ocean and its adjacent areas, passes through the Tamil Nadu and Andhra coasts. Then it reaches the mass nesting beaches in Orissa. There are some information about their nesting in coastal West Bengal. Coastal West Bengal extends from the Sunderban region in the east to Digha-Shankarpur region in the west. The Sunderban holds the world's largest chunk of mangrove forests, while the vegetation of the Digha-Shankarpur coast is primarily casuarina. The entire region is an intensive fishing zone. Large scale trawling related mortalities take place in West Bengal every year. These coasts have not been surveyed adequately to identify the density of nesting of sea-turtles, sea-turtles in off-shore waters and anthropogenic pressure on turtles, their feeding and nesting habits.

OBJECTIVES
The study has been initiated with the following objectives:

1. To identify key nesting areas of sea-turtles and to quantify the density of nesting.
2. To identify the species in off-shore waters.
3. To assess population density traversing off-shore waters along this coast twice in a season.
4. To assess anthropogenic and other factors which hinder the nesting population, nesting beaches and survival of sea-turtles.
5. To create a network which will provide updated information of nesting, mortality and conservation.
6. To formulate a sea-turtle conservation action plan for sea-turtles that nest along the coast of West Bengal.

STUDY AREA
Mechua, Chaimari, Kalash, Bijeara & Jambu Island in Sunderban Biosphere Reserve, Digha, Shankarpur & Junput in Midnapur district for turtle nesting. Namkhana, Canning, Raidighi, Kultali, Basanti for turtle trading.

FINDINGS

HABITAT
Nesting grounds of Sea Turtles are located in the extreme southern part of Sunderban Part of it falls under Sunderban Tiger Reserve and the rest is under Sunderban Biosphere Reserve. Turtles prefer sandy beaches. The entire area fall under estuarine deltaic region of Sunderban. Under the Tiger Project area, turtle habitats are located at Mechua and Chaimari Islands and under Biosphere Reserve; the islands are Jambudwip, Kalash and Bijeara.
The other small nesting ground is situated in a sandy island of Midnapur district. The island is known as Dadanpatrapar. It is close to Contai, a crowded township of Midnapur.

SEASON AND ATMOSPHERE
It has been observed that maximum numbers of nests are found during February and March. The turtles come out of the sea water and crawl up the sandy beaches during the night, lay eggs and go back to sea again during the same night. It has also been observed that the turtles come for laying eggs from one day earlier to 3 days after new moon and full moon. The atmosphere during the period remains foggy and there is a southern wind.

Different temperatures were recorded by the field team during the study.

	Air	Surface	Nest
Mid February	24°C	25°C	25°C
Mid March	32°C	34°C	31°C

Moisture content inside the nest was
50% in mid February and
62% in mid March

DEPARTMENTAL MANAGEMENT

Due to high predation of nests in different nesting beaches, the State Forest Department has developed some Hatchery Centres for marine turtle. At Sajnakhali in Sunderban Tiger Project area hatchery centre has been created. As conservation measures to aid breeding, eggs are collected from Mechua and Kalash, and brought to hatchery centres of Sajnakhali. Generally, it takes 60-70 days for the hatching of the eggs. When the hatchings are two months old, these are released in the creeks near Bay of Bengal, where the nestings are recorded and found.

THE NEST AND MEASURE

Olive Riddleys make their nests above high water marks in dry sandy areas. The nests, which were opened up for the study/were as follows:

Nest No.	Depth	No. of Eggs in one Clutch
1	1.6 feet	75
2	1.9 feet	114
3	1.5 feet	88
4	1.11 feet	106
5	1.8 feet	94

Hatching was studied at Sajnekhali hatching centre, Hatchings come out after 60 to 70 days. They were fed with mashed prawn. The weight of the hatchings varied between 15 and 18 grams. The average length was 6.5 cm. The average length of the front and back flippers were 4 cm. and 2 cm. respectively.

PROBLEMS OF HATCHING EGGS IN SUNDERBAN

The following are the main problems of hatching of eggs in nature in Sunderban, which were observed by the study team:
•  Predation of nests by wild boars and monitor lizards.
•  Destruction of nesting grounds due to erosion and deposition of fresh sands on the nests.
•  Destruction of nests due to fierce wind during depression and cyclone, which often takes place in the coastal zone of Sunderban

PROBLEMS OF STUDY ASSOCIATED
WITH THE SITES OF SURVEY IN SUNDERBAN

1. MOVEMENT OF TIGERS
   The sandheads of Sunderban, i.e. island of Kalash, Bijeara, Mechua and Chaimari re infested with tigers. Some of these tigers are man-eaters. Sometimes, the study team was followed by tigers. So, the team had to be very careful and cautious during the study.
   

2. MOVEMENT OF WILD BOARS
   The movements of wild boars are quite frequent in different islands of the study area. In one occasion, a team member was severely charged by a wild boar.

3. DIFFICULT TERRAIN
   The estuaries of Sunderban are mostly formed by mud, which is very slippery and full of pneumatophores. So, the team members had to be very careful about moving in the study area. Due to the above reason, it was not possible to move in the study area in the early mornings and late evenings. Moreover, the team had to always take the help of armed guards of the Forest Department. The State Forest Department has extended their full co-operation in this respect.

Note : Trawling takes place deep in the sea, far away from these sandheads. Therefore, the possibility of dead turtles floating in these sandheads is remote. So, animals like wild boars and tigers are predators and not scavengers.

THREATS OF SEA TURTLE IN WEST BENGAL COAST

1. TRAWLING
   The main threat of marine Turtles along the West Bengal coast is trawling operation. It has been reported by the Fisheries Department that officially, 1500 trawlers go out for trawling every day in season. So, the unofficial number is much more. The reason of death of the sea turtles is due to suffocation in the fishing net during the trawling operations.

2. WILD BOARS
   Wild Boars are one of the major threats in the coastal regions of Sundarban. Many turtles were found killed and eaten up by Wild Boars. Most of the nests of sea turtles were damaged by these pigs.

3. FERAL DOGS
   In some places like Mohana and Dadanpatrapar in Digha- Shankarpur areas, feral dogs have become threats. During the study, it has been found in some cases that the feral dogs were eating up live turtles.

4. TURTLE MEAT TRADE
   Turtle meat trade is another threat to marine turtles, both in Digha- Shankarpur and Sundarban area. Though the demand for sea turtle meat is not very high in these areas, yet, in season, meat of Olive Ridley turtles are sold in markets of Raidighi, Kakdwip, and Namkhana in Sundarban area and Gharichak, Thakurchak, Botipur and Ramnagar around Digha- Shankarpur areas. The meat is sold at Rs.15 to Rs.20 per kg.

5. TIGERS
   Though not much, the tiger causes some threat to m,arine turtles in the Sundarban area. Sometimes, tiger pug marks have been found around the dilapidated bones and skulls of Olive Ridley turtle, which indicated that the turtle might be killed and eaten up by tigers.

RECOMMENDATIONS :

•  Though order has been passed by the State Fisheries Department to install TEDs (Turtle Excluder Device) in every trawler, yet not a single trawler has affixed TED. It has to be mandatory to install TED in all the trawlers which should be enforced by the administrative authorities.

•  Many nests in the Sundarban are destroyed by wild pigs and monitor lizards. Hence, the Forest Department collects eggs and hatches those in hatcheries. Instead of doing that, 3 feet high fencing encircling the nests may be made by Goran sticks. During the incubation period monitoring should be done regularly, as the hatchlings come out the fencing may be removed so that the hatchlings may go to the sea. Thus in situ conservation may be practiced.

•  Routine patrolling has to be made by the forest department during nesting season to locate nests. The eggs which are laid near the water may get rotten or destroyed by natural calamities. Hence these eggs may be relocated in the hatcheries.

•  Restrictions and regulations should be implemented on mechanised fishing during peak breeding and nesting seasons.
•  A public awareness campaign has to be organised specially by the NGOs in order to keep the turtle habitat free from bio nondegradable articles like polythene and plastic and other toxic materials.

Note: The project is still continuing in collaboration with the Forest department. In 2005-2006, 7,000 eggs have been collected from various nesting pits along the coastal regions of Mechua which has been sent to turtle hatchling center of Sajnakhali. Two pits are conserved in situ.