WWF calls to save the Chinese white dolphins

In 2019 the estimated number of Chinese white dolphins (CWD) around Lantau Island dropped significantly from 47 to 32 individuals; representing an over 80 per cent decline in the overall dolphin population size in Hong Kong since 2003. This is is the report released by the Agriculture, Fisheries and Conservation Department and posted by WWF Hong Kong.




Habitat destruction from coastal development and busy marine traffic are the two major threats affecting their distribution, abundance and behavioural patterns.

Last year, WWF Hong Kong deployed nine hydrophones in West and South Lantau, and around the Soko Islands. Preliminary results indicate that both CWDs and finless porpoises use south Lantau waters, but only for short periods of time in waters close to the existing fairway routes, possibly due to the very noisy marine environment and frequent ship operations.

Busy marine traffic not only increases the risk of ships colliding with cetaceans, it also masks and interferes with cetacean vocalisations on which the animals rely for foraging, socialising and navigation.




However, reclamation works for the Integrated Waste Management Facilities project and offshore pilling works for the construction of a liquefied natural gas terminal in the area pose even bigger threats to dolphin and porpoise survival off south Lantau. Based on WWF Hong Kong acoustic propagation modelling study, the piling noise could potentially spread to the proposed South Lantau Marine Park and damage the hearing ability of marine mammals in the area.
WWH Hong Kong calls for urgent help to support this project, which involves collecting empirical piling data to verify the modelling results. The results will be used to convince the government to designate the western and southern waters off Lantau Island as a dolphin conservation management area, by restricting vessel traffic and speed in the areas found to be critical dolphin foraging and resting habitats.

“Acoustic propagation modelling is a standard practice of underwater noise impact assessment for marine mammals and is widely adopted around the world. It can quantify and estimate the impacts of underwater noise to cetaceans and thereby predict the severity of actual impacts from construction noise. The Government should take this scientifically credible method as a compulsory part of the EIA process in the future,” said Dr. Matt Pine, the Research Fellow at the University of Victoria and external acoustic expert of WWF-Hong Kong’s underwater sound and noise modelling studies. The proposed piling works nullify the efforts of setting up the SLMP that the Government has committed, while underestimating the impacts of noise from construction in EIA report might further threaten the shrinking dolphin group in Hong Kong.

“The Chinese white dolphins of the Pearl River Estuary are globally significant as a vulnerable species under the IUCN Red List of Threatened Species, and an important part of the shared heritage of Hong Kong and Guangdong. WWF believes that the waters of west and south Lantau are one of the few remaining core habitats for dolphins throughout the entire region of the Pearl River Estuary. Chinese white dolphins found in Hong Kong are a key part of the population for the whole region, but extensive, concurrent marine developments in both Hong Kong and Guangdong waters are putting the species in serious peril. For these reasons, cross-border cooperation among administrations is essential to formulate effective conservation and management plans to protect the dolphin population throughout the region,” said Dr. Laurence McCook, WWF-Hong Kong’s Head of Oceans Conservation.

https://www.wwf.org.hk/en/