Photographs by Nick Baker
Indo-Pacific Humpback Dolphin (Sousa chinensis) at Air Papan, Johor, Peninsular Malaysia
Location: Air Papan Beach, Johor, Peninsular Malaysia.
Habitat: Coastal, shallow marine
Date and time: 03 June 2014, 18:45 hrs.
Description of observation: : A dead specimen, with an estimated total length of 2.0 metres, was observed floating in the sea, 100 metres from the beach. Over the next 30 minutes it was pushed towards the shore by wave action, and then finally coming to rest on the beach (Fig. 2.). A group of local people showed interest in the dead dolphin, but did not touch the body (Fig. 1).
Remarks: The subject is identified as Sousa chinensis based on the size and triangular shape of its dorsal fin, and on its relatively long, slender beak. The colour of this specimen is grey dorsally, and white ventrally: the species can vary considerably in colour from grey to pure white to pink, and can grow to 2.4-2.8 metres in length (Francis, 2008).
The specimen showed no obvious external injury, however a constant stream of blood was seen issuing from the corner of the mouth, suggesting it had only recently died from illness or trauma (Fig. 3.). The body appeared fresh, and exhibited no smell.
Sousa chinensis occurs in warmer waters of the eastern Indian and western Pacific oceans, as well as coastal waters in the South China Sea. Jefferson & Smith (2015) list the range countries as follows: Brunei, Cambodia, Indonesia (Sumatra, Java, Borneo), Malaysia, China, Singapore, Taiwan, Thailand and Vietnam (records from other countries are considered as unconfirmed or extralimital). Peninsular Malaysia therefore lies in the heart of the range of this species.
Air Papan is a sandy beach two kilometres in length facing northeastwards to the South China Sea. It is bounded by rocky headlands to the northwest and southeast. It is a popular holiday beach, with a profile that appears to be gently sloping.
- Francis, C. M. (2008). A Field Guide to the Mammals of South-East Asia. New Holland Publishers (UK) Ltd. 392 pp.
- Jefferson, T. A. & Smith, B. D. (2015). Re-assessment of the conservation status of the Indo-Pacific Humpback Dolphin (Sousa chinensis) using the IUCN Red List Criteria. Advances in Marine Biology: Humpback Dolphins (Sousa spp.): Current Status and Conservation, Part 2. 73: 1-21.