A dolphin concern group published on its social media page that one chinese white dolphin (Sousa chinensis) and four finless porpoises (Neophocaena phocaenoides) were found stranded between Saturday the 17th and Monday the 19th of February. Autopsy scans found food remains in the dolphins, showing they were not starved to death. However, they showed multiple fractures. It is feared they were hit by motorboats as they had injuries on their heads and necks.
One finless porpoise was almost cut in half by what is thought to have been a boat propeller.
The adult Chinese white dolphin was found stranded at Mo To Chau. It was a 2.5-meter female, at least 10 years old, and with signs of choking, bone fractures and serious bone dislocation. The death of an adult female is a great loss to the species’ population growth, with numbers in Hong Kong down from over 120 some years ago to 47 at present.
In the past three years there have only been 3-4 stranded cetaceans in tyhe months of January and February. This year, more than 10 dead cetaceans have been discovered in the same period.
High-speed boats are always a big threat to dolphins and some might be hit by propellers and never be discovered. The Dolphin Conservation Society of Hong Kong (HKDCS) has urged the government to launch a speed restrictions on boats around dolphin and porpoise habitats or even ban them from entering these areas.
According to the HKDCS only one new-born Chinese white dolphin was recorded last year. With the loss of another adult female dolphin, there is a dwindling chance of recovery of the local population.
A sperm whale (Physeter macrocephalus) received serious injuries to its tail while caught in a fishing net, which have left it only able to swim in circles, according to news portal chinanews.com (14/3/17).
The whale may have also damaged its sonar system, meaning it cannot find its way back to deeper waters.
The 12-meter-long mammal was found struggling in waters near Shenzhen on Sunday, suffering from several gashes with a tail fin that had been damaged by a fishing net.
Local divers and fishery officials worked together to release it from the net and guide it back to open waters.
However, the animal was too tired to make it away from the shore, and ended up in Huizhou Port on Monday, mere meters from the land. Huizhou is about 50 kilometers away from Shenzhen.
Local officials and 30 experts from the Hong Kong Ocean Park and the Institute of Deep-Sea Science and Engineering under the Chinese Academy of Sciences are monitoring the animal.
One expert suggested luring or driving the whale back to the sea by using whale sounds or those of predators.
However, the expert warned that the whale may have to be poisoned or blown up if rescue efforts fail.
Wu Gang, deputy director of the Huizhou Marine and Fisheries Bureau, said they will first try to treat the whale’s injuries and that euthanasia will only be considered as a last resort.
A dead finless porpoise (Neophocaena phocaenoides) was found in Discovery Bay on Sunday afternoon, the fourth dead marine mammal discovered in four days after the bodies of three dolphins were discovered on Thursday.
It was found in the water and handed over to the Ocean Park Conservation Foundation for an autopsy. The OPCFHK said that the porpoise was a 1.55 metre long female and the body had reached the fourth stage of decomposition. Its cause of death has yet to be determined.
On Thursday, the bodies of three Chinese white dolphins (Sousa chinensis) were found – one entangled in fishing wire near Lido Beach in Sham Tseng, one in waters near Lamma Island and another in Fan Kwai Tong off Lantau Island.
The Hong Kong Dolphin Conservation Society (HKDCS) estimate that there has been a decline since 2014, when 61 dolphins were estimated to be in Hong Kong waters.
A locally-rare finless porpoise (Neophocaena phocaenoides) was found dead in the waters off Shek O, last week (19th November 2015).
The adult female finless porpoise was discovered on Wednesday at Tai Long Pai, bringing the total number of cetacean strandings this year up to 35. It measured 162 centimetres in length and was already severely decomposed. Dissection revealed a fishing rod in its stomach, but the cause of death is still unknown.
Marine Police received information that the corpse of a finless porpoise had been spotted floating near Shek O. The porpoise was then collected and brought to Marine Police Regional Headquarters at Sai Wan Ho, where Ocean Park Conservation Foundation’s Cetacean Stranding Response Team took on the cadaver for autopsy.
Elsewhere in China the Global Times reports another finless porpoise washed up dead in Poyang Lake in Jiangxi Province. Poyang Lake is a freshwater lake which along with the Dongting Lake is host to an estimated 500 finless porpoises. This stranding brings the total for Poyang Lake for 2015 to 5.