Ocean Park Conservation Foundation, Hong Kong Releases 2024 Cetacean Stranding Statistics and Investigation Results of Incidents Caused by Human Activities

Ocean Park Conservation Foundation, Hong Kong (OPCFHK) announces that it has handled a total of 41 cetacean stranding cases in Hong Kong waters together with the Agriculture, Fisheries and Conservation Department (AFCD) in 2024.  These cases involve 30 finless porpoises, four Chinese white dolphins, and seven cetaceans of other species.

Since 2006, OPCFHK’s scientific team has been working alongside AFCD officials to operate the city’s Marine Life Stranding Response Team (the Team), following up and investigating cetacean stranding cases in Hong Kong waters.  When a stranded cetacean is reported to AFCD via the 1823 hotline, the Team would act as first responders to handle the case on-site. In addition, the veterinary, animal care and research experts at Ocean Park would provide technical support to the Team for investigations into the causes of mortality events, collecting valuable scientific data and updating the Hong Kong Marine Life Stranding Database. Over the past 19 years, more than 670 cases have been recorded, ranging from 20 to 50 cases per year.

Human activities threaten cetacean survival
According to data compiled and analysed by OPCFHK over the years, most of the carcasses were found in a severely decomposed state, making it impossible to determine the cause of death. In 2024, OPCFHK observed 14 cetacean stranding cases related to human activities, with six cases in which the cause of death is suspected to be directly caused by human activities. Cetaceans were found to be entangled in ropes, affected by trauma from boat strikes, suffered from infections such as pneumonia, parasites and bacteria, or affected by other internal conditions.

 

	Case 1 In May 2024, a Chinese white dolphin was observed with a rope entangled around its neck in Yi O, Lantau. Since then, the Team has been regularly monitoring and assessing its condition. Despite the encumbrance, it appears to be behaving normally. The Team will continue to monitor the situation closely to determine appropriate actions.
	Case 2 On 3 July 2024, two Chinese white dolphins - an adult female and a stillborn neonate - were found stranded near Pui O, Lantau. Both dolphins exhibited signs of advanced decomposition, making definitive diagnosis challenging. Necropsy findings of the adult dolphin demonstrated bruising and haematoma, which suggested potential blunt force trauma indicative of possible boat strike.
	Case 3 On 30 November 2024, a male adult Longman’s beaked whale (species confirmed through detailed genetic testing) was reported stranded on the beach near Shek Tsai Po, Lantau. The Team, together with Ocean Park’s veterinarians, arrived on-site and initiated rescue actions. Despite intensive efforts to stabilise and refloat the whale. and provide supportive care to mitigate the stress, it succumbed to its weakness and died during the diagnosis. Preliminary necropsy discovered a synthetic bag inside its stomach while the cause of death awaits further examination.
	Case 4 On 10 December 2024, the Marine Police discovered a female adult Chinese white dolphin stranded in the waters near Yi O. It was subsequently handed over to the Team for necropsy.   Necropsy results indicated no wounds on the body. A significant amount of digesta was found in the gastrointestinal tract, suggesting that the dolphin had a good appetite and health condition before death. Conditions observed in the uterus and ovary suggested recent reproduction activity. Multifocal hemorrhages in the lungs and reddish fluid in the trachea were noted, which is suspected to be a result of post-mortem water influx and blood accumulation from the hemorrhages. No abnormalities were observed in the bronchi and bronchioles, indicating no obvious signs of drowning. Veterinary differential diagnoses suggested that the dolphin could have died due to stress and shock. The exact cause of death, however, was unable to be determined from the necropsy.

 

“Cetaceans play a crucial role in maintaining the health and balance of marine ecosystems,” said Paulo Pong, Chair of Ocean Park Conservation Foundation, Hong Kong, and Chairman of Ocean Park Corporation. “In close collaboration with the Agriculture, Fisheries and Conservation Department, and with the support of Ocean Park’s veterinary, animal care and scientific research teams, OPCFHK is taking hands-on action to address the issue of marine life stranding in Hong Kong. Understanding factors such as the causes of injury and death, feeding habits, pollutant exposure and genetic relationships will enable us to formulate more effective solutions and responses for the survival of cetaceans in Hong Kong waters. Meanwhile, we are dedicated to strengthening community education to foster collective efforts in protecting Hong Kong’s marine biological resources.”

Why human activities are possible threats to the survival of cetaceans?
Marine pollution from chemicals, wastewater, plastic debris, and discarded fishing nets and gear severely impacts their biological function, leading to suppression in health. Furthermore, underwater noise pollution from marine traffic disrupts cetacean communication and navigation, hindering their survival and reproduction abilities.

Safeguarding marine life through community action
To reduce the threat of entanglement and plastic pollutants on marine animals, OPCFHK regularly organises coastal clean-ups to remove abandoned fishing gear, commonly called “ghost nets” in Hong Kong, plastic bottles and other rubbish washed up on shores or left behind by people. In 2024, the OPCFHK team, along with volunteers, collected over two tonnes of ghost nets and other marine debris.

OPCFHK also partners with the Hong Kong China Underwater Association to organise the Ghost Net Awareness Enhancement Programme. Supported by the Environmental and Conservation Fund, over 50 diving enthusiasts participated in an indoor training lesson and at least three citizen science activities last year. Through the programme, they learned more about Hong Kong’s marine ecology and biodiversity, ocean plastic pollution and its impact on marine life, as well as the code of conduct and safety of handling marine litter.

Joint efforts for cetacean protection
OPCFHK calls on everyone to help create better habitats for cetaceans and other marine life in Hong Kong.  Recommended actions include:

• Adopt a plastic-free and zero waste lifestyle.
• Do not litter, especially in the sea or on beaches, to protect cetacean habitats and marine ecosystems.
• Fishermen should properly handle and dispose of used fishing gear and nets to prevent them from entering the ocean. The public can also help by disposing of any found fishing gear in nearby bins.
• Be responsible when conducting dolphin watching to avoid disturbing or harassing these animals. Do not touch, feed or harm them. Remind boat drivers to maintain a slow, steady speed and keep a distance of at least 100 metres from dolphin groups. Dolphin watchers are encouraged to read the Code of Conduct for Dolphin Watching Activities issued by AFCD before participating in such activities.

Call 1823 to report cetacean stranding
Members of the public who encounter a stranded cetacean or carcass are urged to report their sightings as soon as possible to AFCD via the 1823 hotline. The provision of relevant information, including date, time and location of discovery, details about the cetacean’s condition and characteristics as well as the caller’s name and contact number, will enable the Team to take timely action and handle the case effectively.

The Team will explore rescue options with relevant authorities and experts for live strandings. In the case of deceased animals, a necropsy will be performed by the Team either on-site or at the Hong Kong Marine Life Stranding and Education Centre in Ocean Park, depending on the carcass's condition.