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St. Martin's Island is a 600 Ha. island lying 10 km south of the southern tip of Teknaf peninsula in the Cox's Bazar District (20°36'N; 92°20'E). Dumbbell shaped and characterised by large areas of sand dune and scattered mangroves, it is the only island in Bangladesh that has coral reef. The climate is governed by the subtropical monsoon, which largely occurs from May-August, with up to 1000 mm of rainfall in a single month. According to older islanders the land was previously covered by abundant tropical evergreen vegetation, although currently the shoreline vegetation is dominated by Screw pine Pandanus sp., Ipomea pes carpeae, and Vitex sp. The circumference of the island is about 8 km depending on tidal level. Three vegetated islands south of the island, locally known as the Cheradia are connected with the main island by a narrow sand belt, fringed with boulders. Thus the total coastal length of St. Martin's is about 14 km, of which 14% or about 2 km is suitable for nesting. Nesting is frequently interrupted by rocks and seawalls and female turtles often make several attempts before successfully laying eggs. Most nesting sites are found on the western coast, while the northern nesting sites are threatened by dogs and local people, being closer to the main business center and fish processing zone of St. Martin's. In comparison, the beaches of the Cheradia islands have characteristics more suited to turtle nesting, with higher slopes and wide sandy areas above the high tide mark even during high tides. Most significantly, the beaches are almost free from disturbance by domestic dogs.

The population of nesting turtles is small. From October 1996 to April 2001, 477 olive ridley and 28 green turtles nested successfully. Hawksbill turtle nests are rare, only one confirmed leatherback nest was observed in Shill Banyar Gula in May 2001, and no confirmed loggerhead nests have been observed. The greatest number of nests recorded in a single season for olive ridelys was 137 in 2000/01 (Table 1). Descriptive reproductive characteristics for green and olive ridley turtles are given in Table 2. The small Cheradia islands could not be observed regularly so all counts should be treated as minima.

The nesting season runs from July until April, but regular nesting occurs largely from October through November, which corresponds to the dry season. Turtles usually emerge to nest between 1900-0300, 3-4 hrs before and at high tide. Turtles emerged in a variety of weather conditions viz. cloudy, clear, slight to heavy wind, and nested on dunes, open sandy beach, under Ipomea vegetation and in the Pandanus groves. L. olivacea and C. mydas seemed to exhibit species specific preferences in when they emerged to nest: green turtles nested only during spring tides, when the tide reached half way up the beach slope, and they tended to emerge several times and excavate several body pits before nesting successfully; olive ridley turtles emerged within 1.5 hours of low tide. Nesting females crawled on average 20-30 m (range 6-64m) from current water level (or between 2-56 m from the HT line) before laying their eggs. At low tides, return crawls could exceed 100 m in length. For L. olivacea the nesting process from body pit construction to covering ranged from 45 minutes to 65 minutes on average, although some can spend more than 3-4 hours during nesting emergences, due to the presence of buried rocks. Some females were impeded from laying by the presence of rocks in the sand, despite as many as 5 to 6 consecutive nesting attempts. In 2000/01, 4 olive ridleys returned to the sea without laying following attempts to dig in a clear sandy beach area (Shil Banyar Gula), and 3 turtles laid within the intertidal zone.

Table 1. Nesting records in St. Martins Island from 1996 to 2001.

Table 2: Summary of nesting characteristics of C. mydas and L. olivacea on St. Martin's island, Bangladesh (nm-not measured).

Stranded dead turtles have been intermittently recorded in Bangladesh. Several dead hawksbill juveniles washed ashore on the northwest beach in November 96 and on the east beach in December 97. The first record of D. coriacea in Bangladesh was one dead adult (CCL 138 cm, sex undetermined) washed up after a storm in April 97.

According to local elders, nesting was common on most of the beaches 10-15 years ago. Rashid (1989) recorded 35 green turtles in one night nesting on one beach. Today a maximum of 7 L. olivacea females were observed nesting in a single night. Although there are no records of C. caretta nesting at St. Martin's, it is possible that they nested on the island in years past. Several causes have been identified for the decline of turtle populations since the 1980s, including deterioration of nesting beaches, high mortality of adults through fishing activities, predation of nesting females and egg collection. Overall, egg collection was rated as the most serious problem (Islam et al. 1999), and not a single nest is safe if not properly guarded (Rashid et al. 1999). Nests were exploited also in the past, but due to the high nest frequency, hatchling emergence was common. Local communities have few traditional uses for marine turtle products. Most of the population is Muslim and do not eat turtle eggs or meat but do trade in turtle products. Three Hindu families live on the island, and before 1996 members of these families collected eggs freely to sell to visitors from neighboring Myanmar and people from the mainland. Eggs are also sold by local collectors to a wholesaler, at Tk 50-200 (approximately US$1-4) per hundred eggs, which are transported to Teknaf by boat to sell to visiting Burmese villagers at higher prices.

Threats due to fishing nets and fishing vessels are severe. Large mechanized fishing boats ply the deeper offshore zone in the south and southwest (Islam et al. 1998). Islanders normally use drift nets, fixed gill nets, rocket nets, seine nets, etc., all of which can result in accidental capture and either drowning or intentionally killing of sea turtles. The fishing community is superstitious and considers the sighting of a turtle or a turtle getting entangled in the fishing nets as a poor omen. Fishermen often kill turtles encountered during fishing activities. The local fishermen normally deny this and blame fishing trawlers from Moheskhali, Cox's Bazar and Chittagong for high turtle mortality. A total of 27 adult and sub-adults turtles of both sexes were found dead on the beaches during 1996-98, more than half of which were believed to be caused by fishing activities. More than 54 dead adult and sub-adult turtles washed ashore during the 2000-01 season. In a study of fishing related sea turtle mortality in 1996 conducted by Marine Fisheries Research Institute (MFRI), it was reported that turtle deaths were not significant (Rashid 1997). However, this report probably underestimated the potential impact of fishing, as turtles continue to be found dead ashore.

Since 1996, success has been gained through several awareness programs, which has helped some of the traditional fisherman view turtles as friendly animals instead of being harmful to their fishing activity. Nevertheless, more work is needed, as most entangled turtles are still found dead. In addition, in Bangladesh TEDs are not used on shrimping boats and the government is taking no initiative to impose any regulations regarding TED use. Another important factor is the soak time and the depth at which other types of nets are set, which can affect turtle mortality.

Fixed gill nets, for instance, remain submerged from 2100-2200 to 0400-0500, and turtles trapped in the early evening drown by the time nets are checked in the morning. The threat to turtles increases when these nets are set near nesting areas. Regulating the location and soak times of fishing nets would also help reduce sea turtle mortality.

Predation of nesting females was severe in the northeast (Delpara) and the north, which are frequented by stray dogs from the nearby villages. These areas are also close to the fish landing and fish processing zone. Nesting olive ridley turtles on the western beaches are also not safe from dogs if not properly guarded. In the last few years, dogs have killed more than 14 olive ridleys on the beach (Islam 1999). This number would have been higher if not for the presence of conservation officers on the beach. Monitor lizards (Varanus salvator) often prey on green turtle nests.

Threats to sea turtles in Bangladesh also include manmade physical alterations such as barriers around the beach. Artificial rock barriers, which impede the emergence of nesting females, were first erected in Konapara and Golachera but are now prevalent in several nesting areas. Before this, nesting was widespread throughout the western beaches according to older islanders. In some places stray boulders from the rock barriers were covered by sand during heavy winter winds, thus creating further problems for turtles attempting to dig their nests. Between 1996-01, at least 32 turtles failed to nest due to the presence of buried rocks, and often times the turtles impeded from nesting are also more vulnerable to predators such as dogs, not only because they spend more time on the beach searching for a suitable nesting site but also because they sometimes must wait for the next high tide before returning to the sea, as they cannot cross the natural rock barrier exposed at low tide. The main nesting beach Shil Banyar Gula is free from this rock hazard. Threats from tourism were negligible before 1995. Now, more people are purchasing land at the western beach, and already one hotel operating on the northwest beach poses a problem with its artificial lights at night. Further tourism development will increase human pressure on nesting turtles during the nesting season. The relevant administrative authorities should impose proper management guidelines for beach use, including control of nighttime lighting (Islam et al. 1999). At least 6 cases are known of olive ridley turtles being frightened away by tourists and dogs in the 2000-01 season.

Prior to conservation activities, personnel of Bangladesh Rifles army detachment (BDR) stationed on the island were either unaware of the importance of sea turtles in the environment or did not show any interest, nor did the government seek to limit any acts of turtle exploitation. Today, the BDR and police have been especially instructed to curb all exploitation of turtles and other wildlife; nevertheless, trade continues in the Teknaf area. Eggs are also collected at the Teknaf peninsular beach and traded in far distant districts such as the town Bandarban (personal observation). Security personnel could easily check for smuggled eggs before the departure of every passenger boat, but policemen do not stop the smuggling of eggs and corals. With the support of local people, the Coast Guard and police, egg collection could be vastly reduced. In order to save the remaining turtle populations, laws regarding fishing, egg collection, beach use and the control of predators should be immediately drafted and imposed. It is hoped the situation will improve through the Marine Park Project by MOEF, which began in June 2001.

Acknowledgements: In Bangladesh, the Marine Turtle Conservation Program on St. Martin's island was started in 1996 by CARINAM with the support of the MTSG.

AHMED, B., K.M.N. HUDA & G.S.M. ASMAT. 1986. The breeding of the olive ridley. Lepidochelys olivacea Eschscholtz at St. Martin's island, Bangladesh, Bangladesh Journal of Zoology.14: 59-68.

Groombridge, B. & R. A. Luxmoore, 1989. The green turtle and hawksbill (Reptilia: Cheloniidae): world status, exploitation and trade. Secretariat of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, Lausanne, Switzerland, 601 pp.

ISLAM, M. Z. 1999. Threats to sea turtle population in Bangladesh. Technical Report. MarineLife Alliance, 1998, 28 pp.

ISLAM, M. Z. 2001. St. Martin Pilot Project, National Conservation Strategy (NCS) Implementation Project-1, Final Report, Ministry of Environment & Forest, Government of the Peoples Republic of Bangladesh, 2001, 119 pp.

ISLAM, M.Z., M.S.ISLAM & S.M.A. RASHID. 1999. Marine turtle conservation program in St. Martin's island, Bangladesh by CARINAM: A brief review. Tigerpaper 26: 17-28.

RASHID, S.M.A. 1997. Bangladesh National Report for the Northern Indian Ocean Sea Turtle Workshop and Strategic Planning. 13-18, Jan 1997. Bhubaneswar, India. 16 pp

RASHID, S.M.A. & M. Z. ISLAM. 1999. Establishing marine turtle hatchery in Saint Martins Island, Bangladesh. Proceedings of the 4th Asia-Pacific NGOs Environmental Conference, 26-27 Nov 1998, Singapore, Published by the Department of Biological Sciences, National University of Singapore. pp. 255-264.