LETTER TO THE EDITOR
It is with great regret that I have to report the possible terminal decline of Hoi Ha Wan Marine Park. This marine park was the first to be designated in Hong Kong; it could possibly be the first to be delisted owing to the complete destruction of the marine life within it. It could very likely become Hong Kong’s first Marine Desert.
In January this year divers carrying out monitoring training noticed that a substantial amount of the park’s corals at the northern end of the park, close to Moon Island and Flat Island, had been completely destroyed as an infestation of sea urchins attracted by nutrient algae, had eaten not only the corals but also their skeletons. Nothing remains except the underlying rock. Roughly 25% of the marine park corals have gone – forever, some being over 70 years old. At the last Reef Check in 2015 there was no indication of any problems; the corals were healthy, as confirmed on the AFCD website.
In early February 2016 Hoi Ha Wan suffered an unusual hypoxic event. Most of the marine life in the bay, along with another 30~40% of the corals, was wiped out. No fish, no eels, no crabs– all gone. This event was triggered by a build-up of nutrient algae, and this is what also attracted the sea urchins that ate the coral in January. Recent reports from the village stated that the seahorses were safe at the pier; sadly there are none there anymore.
This algae build-up was due entirely to an increase in nutrients in the bay. Theses nutrients came from a number of sources. Human effluent from leaking septic tanks along the foreshore of Ho Ha village as well as grey water from the village, organic nutrients washed down from the agricultural activities recently introduced to Pak Sha O, and finally organic and sedimentary nutrients washed out by recent heavy rains from the flood plain that was cleared adjacent to the village last summer by developers readying the area to build houses in the areas newly zoned for such by the Town Planning Board.
Only quick and resolute action can stop another such traumatic event killing off any remaining marine life in the marine park. First, Hoi Ha country park enclave must be zoned Country Park as soon as possible. All zones – Coastal Protection Area, Green Belt etc – must go. They provide no protection at all. Secondly, the draft Outline Zoning Plan for Pak Sha O must also be changed so that no V zone is allowed on the wetlands and all agricultural activity must stop. Again, the enclave should be fully integrated into the Country Park as soon as possible. As usual with the enclaves, the Town Planning Board zoning was made without any scientific input; no independent environmental impact assessment was carried out to identify the sensitive receivers or propose environmentally sustainable solutions to the existing impacts, and to future possible impacts to the area.
Thirdly, a mitigation action plan must be activated quickly. This will take time and money, and it is possible that the marine park will never be restored to its previous glory. The Town Planning Board are the originators of this mess; AFCD are the ones who are going to have to clear it up. We should all support AFCD’s efforts in whatever way we can.
Dr Robin Bradbeer
Secretary, The Professional Commons