Movements of Olive Ridley Turtles (Lepidochelys olivacea) in the Bay of Bengal, India, Determined via Satellite Telemetry

Abstract The migratory movements of 14 olive ridley turtles (Lepidochelys olivacea) in the Bay of Bengal were studied using satellite telemetry during 2009–2010. Tracking data show that olive ridley turtles undertake open-ocean migrations in the bay and exhibit migratory corridor between foraging habitat of Sri Lanka and nesting sites along the Odisha coast of India. Tracking durations ranged 7–331 d (mean = 151 ± 95.9 d). The tracked turtles had a mean traveling speed of 2.49 ± 0.02 km/hr and moved an average of 31.7 km/d, remaining within a mean distance of 163.28 ± 50.9 km (range, 1–535 km) from the east coast of India. Turtles occupied waters with sea surface temperature (SST) ranging from 24°C to 31°C with chlorophyll concentrations of 0 to 3.9 mg/m3. Our study confirms that olive ridley turtles in the Bay of Bengal move within a broad range of SSTs and chlorophyll a concentrations; no correlation was found between turtle movements and these 2 oceanographic parameters (r2 = 0.02, n = 77). Our data indicate that many habitats within the Bay of Bengal are important for olive ridley turtles and that the entire bay should be considered a priority conservation region for this vulnerable species.