Fig. 1. Carcass of a Green Turtle (in foreground) floating at Selat Pandan.
Fig. 2. Ventral view of Green Turtle carcass showing: a) single claw on front flipper, b) spilt guts, and c) crack line on the plastron.
Photographs by Tan Yee Keat
Green Turtle (Chelonia mydas) carcass showing sign of boat strike at Selat Pandan
Location, date and time: Singapore Strait, Selat Pandan off Jurong Island; 9 June 2015; 1150 hrs.
Observation: A carcass of a marine turtle, with estimated plastron length of between 50 and 60 cm, was found floating at sea along a hectic shipping lane (Fig. 1). It had spilt guts (Fig. 2b) and a crack line on the plastron (Fig. 2c).
Remarks: The single claw on both front flippers (Fig. 2a) and relatively small blunt head identify the carcass as a Chelonia mydas (see Gomez & Miclat, 2001). Although quite commonly sighted around the islands in the Singapore Strait (Tan, 2010), the green turtle is regarded as a ‘critically endangered’ species in Singapore (Lim et al., 2008).
The featured turtle seems to have been dead for at least two days. The large crack line on the animal’s plastron suggests that it was cut by a boat propeller, and had possibly succumbed from the injury. Compared to fast-swimming cetaceans, marine turtles and Dugongs tend to be slower in their movements, and appear to be more vulnerable to morbidity and mortality by boat strike (Davenport & Davenport, 2006). The adoption of ‘Go-Slow’ or speed restriction zones (less than 4 km h-1 according to Hazel et al., 2007) may be necessary to mitigate collision risks in areas where turtles tend to frequent, such as over seagrass beds, their foraging habitat. This measure is imperative to protect this endangered animal in Singapore’s marine environment, which is one of the world’s busiest ports (Chou, 2008).
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