OLIVE RIDLEY SEA TURTLES WASH ASHORE DEAD BEARING VESSEL STRIKE INJURY ON KOLLAM BEACH, INDIA

PATHISSERY JOHN SARLIN¹, SANCIA MORRIS^2,#, SANDIE MORRIS³, SAVIO MORRIS⁴ & POLYCARP JOSEPH³

¹PG and Research Department of Zoology, Fatima Mata National College (Autonomous), University of Kerala, Kollam, India

²Institute of Chemical Technology Mumbai, IOC Bhuvneshwar, Odisha, India

³Kollam Birding Battalion, Kollam, India

⁴Trinity Lyceum, Kollam, India

^#sanciamorris@yahoo.com

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Olive ridley sea turtles (Lepidochelys olivacea) nest in Kerala from October to March each year. The number of turtles nesting annually is unknown, however the number of nests laid each year have decreased over time (Laladhas et al., 2016).

On 16^th September 2023, we observed a dead olive ridley turtle (straight carapace length ~60cm; short tail length) stranded on Sakthikulangara Beach (8.93679° N, 76.54324° E), approximately 200m from the Sakthikulangara wharf at the largest fishing harbour in Kerala. The carapace was fractured, and the soft tissues were decomposing (Figure 1). Another olive ridley turtle washed ashore, almost midway between the first stranding site and the harbour, on 23^rd September 2023. This turtle also had a broken carapace and was in a more advanced stage of decomposition (Figure 2). Carapace length of the second turtle was not measured; tail length did not extend beyond the carapace. Both carcasses were buried on the beach by the Forest Department officials.

Figure 1. Dead olive ridley turtle on Sakthikulangara Beach, Kerala, on 16^th September 2023. (Photo credit: C.P. Christopher)

Figure 2. Dead olive ridley turtle on Sakthikulangara Beach, Kerala, on 23^rd September 2023. (Photo credit: Sandie Morris)

Damage to the carapace of both turtles is consistent with boat strike. It is more likely that the boat hull struck the turtles, causing the laceration, and not propeller, which usually results in parallel, evenly spaced lacerations (see Phillott & Godfrey, 2019). It is not clear if the injury was the cause of the turtle death, or if it occurred post-mortem. Stranded turtles along the Kerala coast have been rarely reported. The five existing reports, include this record of two dead olive ridley turtles, a dead leatherback (Dermochelys coriacea) turtle (Anil et al., 2009), other dead olive ridley turtles (Vizhinjam & Baby, 2012; Sreekumar et al., 2016), and a live olive ridley turtle (Saleem et al., 2019). All the strandings occurred during the nesting season (October to March). Pathissery & Heeralal (2021) also report the death of a nesting olive ridley turtle as a result of stray dog attack in the Sakthikulangara Beach. Olive ridley turtles are included in Schedule I of the Indian Wildlife (Protection) Act, 1972 and thus receive legal protection. Stranded turtles have been reported from this area in Kerala, but stranding observation networks are inefficient or non-existent in some of the state’s coastal districts so this will be an underestimate of the number of strandings. Strengthening the conservation efforts of citizen science groups and volunteers along with effective monitoring for dead turtles and relevant data collection would determine the true scale of strandings. 

As sea turtles regularly occur in the waters around Kerala, increased public awareness may help reduce threats and lead to beneficial actions, such as rescue, rehabilitation and, hopefully, release of stranded sea turtles as well as improved reporting rates of dead sea turtles along the coast to help us better understand both the occurrence and threats faced by these species.

Acknowledgements 

Our sincere thanks are due to the photographer Mr C.P. Christopher, Forest and Wildlife Department of Konni Division, Coastal Police of Kollam, Fatima Mata National College (Autonomous), Kollam for their valuable assistance and logistics department.

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