The rough-toothed dolphin Siu Tik, who was stranded and then rescued at Lok Tik Wan in May last year, died at Ocean Park yesterday after months of intensive treatment and expert care by Ocean Park and the Agriculture, Fisheries & Conservation Department.

Preliminary results of a thorough post-mortem examination performed yesterday indicated that the animal had gastric problems and diseases in different parts of his body.

Samples were collected for laboratory investigations to determine the cause of Siu Tik's death and, if possible, why he was stranded 10 months ago.

Siu Tik had not been able to eat unassisted since his rescue, even though he improved during his recuperation in Ocean Park. His weight increased from 75kg to more than 100kg.

Repeated tests over several months did not determine why Siu Tik failed to fully recover.

The department said Siu Tik's case had provided a valuable lesson in veterinary care for stranded dolphins, including the biology of the species to better understand and prepare for future strandings.

Siu Tik's skeleton will be kept for public educational programmes for the conservation of marine mammals.