A Victoria Harbour with thriving corals shows progress, conservation can go hand in hand

There seems to be no conflict between economic development and environmental conservation, a City University researcher says after finding 35 species of coral in Victoria Harbour, signifying an improvement in water quality.

CityU researchers found significantly more coral in the harbor than expected: five habitats with the biggest at Fat Tong Chau in Tseung Kwan O covering 10 hectares or the size of 14 football pitches.

With the help of divers, researchers surveyed 12 sites along the sides of Victoria Harbour, including seven natural coastlines and five artificial breakwaters, between June 2021 and June 2023, to find out the distribution and condition of corals and map inshore underwater habitats.

Speaking on radio yesterday, Leo Chan Lai, associate director of the State Key Laboratory of Marine Pollution at CityU, said the team found four black coral species, 16 stony coral species and 15 octocoral species.

"Corals can only survive in clean water and it is a surprise to find so many coral species in the harbor," Chan said. "The result indicates that the water quality has significantly improved."

He said a halt in land reclamation has offered breeding grounds for marine life, including the harbor treatment scheme, which began in late 2015 to collect and treat sewage.

Researchers also identified five essential benthic habitats - or the bottom of a body of water - among which the biggest one in Fat Tong Chau covers about 10.42 hectares.

Apart from corals, Chan said the team found a high density of scallops, which are also very picky about water quality.

Double-ended pipefish and festive sea slugs, which also require clean water, were found near the Hong Kong Museum of Coastal Defence. The resting habitats were found on the seabed near Green Island off the northwest coast of Kennedy Town, Cape Collinson Lighthouse in Chai Wan and Devil's Peak in Yau Tong.

"The [research] reveals that there is no conflict between economic development and environmental conservation," Chan said, urging the shipping sector to adopt green fuel.

ayra.wang@singtaonewscorp.com