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Marine Turtle Newsletter 110:4-5, © 2005

Marine Turtle Newsletter-Online

Strandings of Green Turtles along the Saurashtra Coast, Gujarat, India

P. Kannan, S. Venkatesan, M. Rajagopalan & E.Vivekanandan
Madras Research Centre of Central Marine Fisheries Research Institute, 75, Santhome High Road, Chennai, India – 600028 (Email: perukan@hotmail.com)

In India, much bycatch due to unregulated fishing by trawlers and gill nets has been highlighted in the last two decades (Rajagopalan et al.1996; Shanker et al. 2004). Here we catalogue the patterns of stranding of the green turtle (Chelonia mydas) along the Saurashtra coast, Gujarat, western India as strandings are a likely proxy for local marine turtle bycatch.

The state of Gujarat has a coastline of more than 1600 km and constitutes around 22% of the total coastline (7100 km) of India. The mechanized fishing fleets of Gujarat have expanded in recent years (presently about 18,536; Narayanan 2003). About 24% of the total fishing fleet (6948 crafts) consists of demersal trawlers. The nesting of the green turtle and olive ridley turtles (Lepidochelys olivacea) has been reported in the Gujarat coast (Bhaskar 1984; Sunderraj et al. 2001; Venkatesan 2004). The sea grass beds and coral reefs
in this area provide habitat for a considerable population of green turtles (Siraimeetan 1985).

The present investigation on the strandings of sea turtles was carried out from Somnath to Okha in Jamnagar, Junagadh and Kachchh districts. The survey area was divided in to 15 transects (Somnath, Veraval, Mangrol, Shill, Athroli, Madhavpur, Chingariya, Gorsar, Diwasa, Odathar, Narwaimandir, Porbandar, Dwarka, Okha and Bewt Dwarka) and each transect was surveyed twice by foot during the survey period from December 2001 to February 2002. Dead and stranded sea turtles were counted during the survey and probable cause of mortality was assessed. Morphological measurements were taken according to Bolten (1999).

During the study period, a total of 69 stranded green turtles were recorded along the Saurashtra coast. No other sea turtle species were recorded during this study. All the stranded turtles were found dead on the beaches. Males, females and sub-adults were encountered during the survey (Table 1). Strandings were comparatively higher along nesting beaches such as Shill and Okha beach (14.4 %), followed by Veraval and Porbandar (11.5%), Mangrol (9%), Madhavpur (7.2 %), Dwarka and Gorsar (6 %), Somnath, Bewt Dwarka and Athroli (4.3%), Diwasa (2.8 %), Chingariya (1.5%) Narwaimandir and Odathar (1.4 %). In the Shill
and Okha beaches, there were more males (22.4% and 12.9%)whereas in Okha, Porbandar, Dwarka and Veraval beaches there were more females (17.6%, 14.7% 11.7% and 11.7%) (Table 1).

The mean curved carapace length of 69 green turtles was 85.6cm (SD: 22.3), mean curved carapace width was 77.2cm (SD: 19.3 cm), mean plastron length was 66.8cm (SD: 16.9 cm), and mean plastron width was 65. 5cm (SSD: 16.4 cm). Mean body weight was 71.8kg (SD: 25.6; Table 2).

Although a total of 69 adults is not very large, this represents a conservative estimate and may be a small proportion of turtles dying in offshore waters in a small portion of the year. The bias of the stranded turtles to large individuals is cause for concern and worthy of further investigation.


Figure 1. Map of Gujarat showing the study area. Produced using Maptool provided by SEATURTLE.ORG.


Table 1. Strandings of green turtles along the Saurashtra coast, Gujarat.


Table 2. Morphometric measurements (cm) and weight (kg) of the green turtle Chelonia mydas. Range is given in parentheses.

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BOLTEN, A.B. 1999. Techniques for measuring sea turtles. In:K.L.Eckert, K.A. Bjorndal, F.A. Abreu-Grobois & M.Donnelly (Eds). Research and management techniques for the conservation of sea turtles. IUCN/SSC Marine Turtle Specialist Group Publication. 4: 110-114.

NARAYANAN, K.R. 2003. Status of marine Fisheries development of Gujarat: An overview. Fishing Chimes 23: 7-15.

RAJAGOPALAN, M., E. VIVEKANANDAN, S.K.. PILLAI, M. SRINATH & A. BASTIN FERNANDO. 1996. Incidental catch of sea turtles in India. Marine Fisheries Information Series 143:8-16.

SHANKER, K., B. PANDAV & B.C.CHOUDHURY. 2004. An assessment of olive ridley (Lepidochelys olivacea) nesting population in Orissa on the east coast of India. Biological Conservation 115:149-160.

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SIRAIMEETAN, P.1985. Observations on the green turtle Chelonia mydas along the Gujarat coast. Proceedings of Symposium on Endangered Marine Animals and Marine Fishes 1:290-297.

VENKATESAN, S. 2004. Ecological and physiological studies on the green sea turtle Chelonia mydas. PhD.,thesis. University of Madras. Chennai, India, 112 pp.