A live Striped dolphin (Stenella coeruleoalba) was found by three hikers stranded on the beach of Sai Kung Tung Wan at around 5pm yesterday. The hikers reported it to police and attempted to return the dolphin to the sea. However the dolphin could not swim or surface to breathe on its own, so the hikers supported the dolphin until the Agriculture, Fisheries and Conservation Department (AFCD) and Ocean Park Conservation Foundation Hong Kong (OPCFHK) Cetacean Stranding Response Team could arrive at the site at 9pm to coordinate the rescue. The dolphin had many visible external wounds, AFCD and OPCFHK had therefore decided to transport the dolphin to Ocean Park for medical treatment late last night with the help of the Ocean Park veterinary and marine mammal teams.
The sub-adult male dolphin, measuring 2.05m and weighing 68kg, underwent examination, treatment and overnight observation, while remaining supported in the water so he could breathe. Healthy male adult Striped dolphins reach up to 160kg in weight and 2.7m in length, while the stranded dolphin was over 20% below the expected normal weight for its length. After a night of rescue efforts, the dolphin passed away at 11:46am this morning. Necropsy of the dolphin indicated acute hemorrhagic pneumonia and associated sepsis involving all lymph nodes, liver and spleen.
Ms Suzanne Gendron, Foundation Director of OPCFHK, said, “Given the dolphin was extremely weak and had multiple external wounds, it was already a miracle that we were able to bring it back to Ocean Park for treatment after it was found beached in Sai Kung. We would like to thank the various government departments, as well as the three hikers and campers who attended to the stranded dolphin for their incredible support. Those people did a great job in moving the dolphin back into the water, keeping its skin moist and its blow hole above water so it could breathe. Their efforts enabled our teams, together with the AFCD to arrive on site and recover the dolphin for treatment and supportive care.”
There have been five previous strandings of striped dolphins in Hong Kong prior to 1996 and this is the first live stranding case for this species known to have occurred in our waters. Ocean Park has handled two live stranding cases in the past, including an old Chinese white dolphin that stranded in a river at Sam A Tsuen of Shuen Wan in 2003, and a rough-toothed dolphin in 2004. Both stranding cases survived only a short time with the rough tooth dolphin surviving for ten months.
Striped dolphins are a medium-sized species with a light gray blaze running from the flanks to under the dorsal fin, and having a dark gray back. This species has bold, black stripes that run along the sides of its body from the eyes to the genital region. Striped dolphins reach lengths of up to 2.7 m with an adult weight of around 160 kg. Calves are born at approximately one meter in length. They are usually found in tight, cohesive groups averaging between 25 and 100 individuals, but have been occasionally seen in larger groups of up to several hundred and even thousands of animals. Within these schools there is a complex system of individuals that may be organized by age, sex, and breeding status. They are widely-distributed but mainly found in tropical and warm-temperate waters of all the major oceans, and many adjacent seas, including the Mediterranean. However, some records in higher latitudes show this species may be more tolerant of cooler waters than other tropical species.
