The false killer whale found beached off Sai Kung this week died from lung failure, according to preliminary results from a post-mortem examination.
The juvenile member of the dolphin family, first spotted at Tai Long Sai Wan on Monday, had swollen lymph nodes and a tumor on its lungs which might have caused it to beach itself, Agriculture, Fisheries and Conservation Department senior veterinary officer Trevor Ellis said yesterday.
'It had fairly severe lung changes which are sufficient to explain the death but we still need to undertake microbiological, histological and toxicological tests which will take at least a couple of weeks,' Mr Ellis said. 'It is quite an interesting and relatively fresh specimen, so the chances of getting an explanation [of the cause of death] are quite good.'
He said large gashes on its head would have been inflicted when the waves washed its body back to shore, dashing it against rocks.
The dolphin was found dead on Tuesday after it was washed out to sea following a failed rescue attempt the day before. The man who first found it said police and officials bungled the operation.
Ocean Park marine mammal curator and veterinarian Crista Rayner said although species such as false killer whales had been known for mass-strandings, most whales and dolphins which beached themselves did so alone and in a weakened condition.