By Tim Collard

As is widely acknowledged, the 2012 trawler ban in Hong Kong waters was an important step forward in the process of re-establishing a healthy marine environment (and fisheries), and it is having a beneficial effect. When diving in Mirs Bay a visible return of fish species not commonly seen for years is apparent. However, the past two years’ gains are being compromised by developers and their increasingly large-scale “small house” construction projects inside the Sai Kung Country Parks, as well as their re-introduction of farming along the stream that flows into the Hoi Ha Marine Park and its protected coral reef areas.

In the 1960s, small coral reefs were common in the area – sadly, this is no longer so. While the decline has likely been due to pollution, widespread bottom trawling, and construction on both the Guangdong and Hong Kong sides of the bay, the underlying cause is increased silt, chemical pollutants in the silt itself, and increased drainage from human settlements in the area. This seriously damages the marine environment, including corals and mangroves, which are critically important breeding grounds for many fish, including high value garoupa, snapper and bream which are important to both “capture” fisheries and as a source of juveniles for Hong Kong’s fish farming industry. Environmental degradation in Mirs Bay affects not only the natural beauty of the area but also the livelihoods of thousands of lower-income people. According to the Agriculture, Fisheries & Conservation Department (AFCD) website, both capture fisheries and fish farming were valued at approximately HK$2.4 billion in 2013.

Since 2013 at Pak Sha O, former rice land, now owned by a developer, is being cleared for intensive vegetable cultivation by non-indigenous outsiders in a ploy to drain a wetland in preparation for large-scale construction of small houses. While farming is not a long term business for the developer, I believe it does have the ability to seriously disrupt the Hoi Ha Marine Park downstream of Pak Sha O because, apart from the chemical (pesticide and fertiliser) inputs, the drainage system of the land, which has lain fallow for decades, is being altered.

Farming has occurred in the Hoi Ha valley for centuries and co-existed with a thriving marine environment, so why do I now think this is not a good idea? The answer lies in the type of farming: the original indigenous Hakka farmers of the valley reclaimed the land primarily for rice cultivation. And, they did it very gradually by hand, minimising negative environmental impacts over time. They did not use the mechanical diggers that are being used at Pak Sha O to build drainage ditches and clear forest in days. Also, the Hakka farmers used the natural forces of nature to irrigate the rice fields that were, in effect, man-made wetlands and remained that way until 2013. The modern vegetable farmers are doing the exact opposite because their objective is drainage not irrigation. While the Hakka farmers retained water and topsoil in their rice fields, the present day vegetable farmers must get rid of excess water, and in so doing they lose topsoil and with it soil nutrients and fertility. Furthermore, intensive vegetable cultivation requires significant inputs of chemical pesticides, and fertilisers to compensate for the loss of topsoil. The inevitable result is an increase in silt runoff into the Hoi Ha Marine Park and in the water (including toxic pesticides and chemical fertilisers, both of which are harmful to the marine environment).

The developers’ plans in Hoi Ha and Pak Sha O to prepare for large-scale construction of small houses are self-evident because they are developers: that’s their business, not vegetable cultivation. Modern intensive vegetable farming, the extensive development of various kinds contemplated under the Hoi Ha and Pak Sha O Outline Zoning Plans (representing the Town Planning Board’s vision for future development in the village enclaves within the Country Parks) – including AFCD’s own planned visitors centre – will surely be the death of the Marine Park.

In my opinion, AFCD is faced with a very difficult situation: to do nothing now will be to allow developers and the Planning Department to proceed as they clearly intend, and will result in irrevocable damage to the Hoi Ha Marine Park. On its website AFCD has called for new marine reserves, but if the department can’t protect and conserve what it already has, then why should Hong Kong people entertain an increase in its budget for this admittedly worthy initiative? As I see it, recent developments throughout Hong Kong’s Country Parks and in the village enclaves within them call into question the purpose and existence of AFCD.

Tim Collard has lived in the village of Pak Sha O(白沙澳), close to the Hoi Ha Marine Park, for 10 years. He was born and brought up in Hong Kong and has a degree in zoology. Since the 1960s he has been a keen SCUBA diver, and is familiar with the Mirs Bay area and its ecology.