All About Green

To Restrict or Not to Restrict? That is the Dilemma of Ecological Carrying Capacity

Green Country Vol.124 (Feb 2017)
Author: Green Power
A large number of people watching Sweet Gum Liquidambar formosana at Tai Tong
Crowds at Tai Tong, observing and photographing autumn colours of Sweet Gum.
© Carrie Ha

In recent years, natural attractions in the countryside have attracted considerable media attention. For example, watching Sweet Gum (Liquidambar formosana) at Tai Tong, sunset at Ngong Ping above Ma On Shan, Silvergrass (Miscanthus spp.) at Sunset Peak and fireflies at Tai Po Kau…. Remote and peaceful rural areas become well-known and attract crowds all of a sudden, resulting in piles of rubbish and noise, and damage to local plants and animals. Overloading the environment causes adverse impacts on ecosystems. How do we calculate the ecological carrying capacity, and how to implement restrictions of visitors in nature would be a difficult question!

The tranquility of the countryside makes it ideal for urban dwellers to relax and take a break from their daily business. It is also a matter of life and death for wild animals. Hence landuse planning and infrastructure for the countryside differ from urban and village uses. The setting up of country parks, for instance, was meant to protect water catchment areas and the natural ecosystems, while allowing people to carry out leisure and nature education activities.

The topsoil of the steps on the trail are eroded because of excessive use
Overuse of hiking trails causes wear and tear and soil erosion.
© Henry Lui

However, when the number of visitors exceeds a certain level, it will bring various degrees of damage. Firstly, large number of visitors causes wear and tear and even direct damage to facilities in the countryside, such as hiking trails and steps. Overuse of them accelerates soil erosion and wear and tear. Vegetation is stepped on or harmed when camping tents are set up. Soil is compacted, making it hard for vegetation to revive. In more severe cases, such as the grassland on Tap Mun, the land suffering such destruction cannot be restored. Vulnerable geological environments such as with sedimentary rocks can be permanently eroded by reckless steps of visitors.

On the Ngong Ping Grassland in Ma On Shan, a cattle searched for food among the garbage left by citizens
Recently, there was a report that a wild cattle at Ngong Ping above Ma On Shan threw up after consuming rubbish left behind by irresponsible campers.
© Candy Yau

Trash is among the most serious problems caused by irresponsible countryside visitors. Food packages, containers, disposable cutlery and food waste are commonly found in the wild. Near barbecue areas or camp sites items discarded can even included tents, cooking utensils, barbecue forks, charcoal, wire, and gas cans.… There ere recent news reports saying that after the long Xmas and New Year holiday, mounds of rubbish were found in various camping locations. There was even a report of wild cattle getting sick after eating the rubbish. Every year, over 3,000 tonnes of trash are collected in the country parks; far more is simply scattered across hill slopes. The Agriculture, Fisheries and Conservation Department is collaborating with various groups in the Take Your Litter Home campaign, hoping to alleviate the problem.

Traffic is yet another challenge. Rural roads are usually designed to handle low traffic flows. Congestion, air pollution and noise are some problems caused by excessive traffic. On the other hand, no matter whether visitors use public or private transport, demand on roads and for parking space is also an issue. In reality, some greenbelt sites are illegally reclaimed by concrete, and transformed into car parks for such purposes.

The countryside is home to many species of wild plants and animals. Too many visitors bring nightmare situations for these living things, particularly the more sensitive and vulnerable ones, such as birds that are shy, and large mammals including Red Muntjac and Wild Boar. Rare and precious plants such as wild orchids may also be damaged by being picked or stepping on by visitors.

Therefore, calculating the carrying capacity and restricting visitor numbers in the countryside becomes essential. In Hong Kong, there are few places with such restrictions. But there are many examples of such regulation in ecological hotspots and national parks in other countries.

Complicated calculation

There have been overseas studies on ecotourism that calculate the carrying capacity of certain tourist spots according to the facilities and lodging space. Yet “acceptable visitor load” is not a single figure. There are seasonal and regional variations, and individual situations and experience must be taken into account to establish different restrictions.

It is relatively easy to calculate the acceptable visitor load with reference to the number and durability of facilities. Yet studies sometimes find it hard to take into account the carrying capacity of an ecological hotspot, or simply overlook doing so. The loss of a notable site for nature includes damage to vegetation as well as disturbance to animals. It takes a wide spectrum of knowledge of plants and animals, habitats, and information on species resilience and ability to recover from human interference. There is little research on such topics. The special conditions and ecological combinations in different places make it extremely complex to assess the carrying capacity of actual sites of ecological value.

Uncontrolled clam collecting activities in Tung Chung Bay
Uncontrolled clam collecting activities in Tung Chung Bay during low tides have caused trouble for mudflat habitats in the estuary.

Besides the number of visitors, their behaviour also makes a difference. Much damage can be done if visitors walk around carelessly, make loud noises, pick up plants and play in water. To calculate the ecological carrying capacity, one has to consider visitor frequency, duration of stay and distribution. As habitats may be irreversibly damaged, the Precautionary Principle should be in place for areas of high ecological value, to partly or completely restrict entry by visitors.

Crowd control becomes common practice

Nature reserves and national parks in other countries often have visitor and vehicle limitations. At Phillip Island Penguin Parade in Australia, a spectator platform has been built at the back beach, to allow a fixed number of visitors to watch. And no flash is allowed in taking photographs, to avoid disturbance to the penguins. Visitor restrictions can ensure that tourist hotspots do not get overcrowded even in peak season, which is good for both the visitors and the ecological environment.

In Hong Kong, visitor limitation is also applied to certain sites of high ecological value. Mai Po Nature Reserve, for example, is managed by an environmental group, while entry permits are issued by the Agriculture, Fisheries and Conservation Department. There is also a limit on visitor numbers for the Hong Kong Wetland Park. Visitors must purchase tickets to enter the park, which is open only for a certain period of the day. The park is also designed to concentrate visitors at Wildside Walk and Bird Hides, so that distance is kept between visitors and wild animals, particularly waterbirds. Some core areas in the park are closed to visitors, to serve as refuges for wildlife. Sham Wan on Lamma Island is a highly sensitive ecological site, as it is a breeding ground for Green Turtle (Chelonia mydas). Staff from the Agriculture, Fisheries and Conservation Department are stationed in the bay during the breeding season, and prohibit entry by visitors during that period.

However, these are only the best examples. In most cases, Hong Kong people can easily gain access to places with high ecological value. At present, the government designates specific landuses such as Sites of Specific Scientific Interest, Conservation Areas and Coastal Protection Area, etc. These can only help protect the land from destruction by development but not the damage arising from excessive visitors.

Minibus station at Shing Mun Country Park
Traffic restriction is an indirect way to control numbers of visitors to the countryside.
© Henry Lui

Infrastructure such as transportation can encourage visitors, as well as serve as a way to restrict visitors. For instance, Pak Tam Chung is on the road to Hoi Ha Wan Marine Park, Sai Kung. Traffic numbers are restricted on the road beyond Pak Tam Chung, in turn restricting the number of visitors to the marine park. Another example is Shing Mun Reservoir, where parking spaces are limited and the road cannot accommodate large numbers of private cars. Visitors can only arrive by public transport, and the carrying capacity of public transport serves to limit the number of visitors.

Apart from traffic restrictions, the government can limit numbers of visitors and their activities by specifying activities in certain areas. For instance, snorkelling is only allowed in designated regions of marine parks; similarly, there are designated camping and barbecue sites in country parks. Such activities are prohibited outside the designated areas. In addition, it is possible to encourage hikers to only walk on the main trails by avoiding labelling the more hidden paths on the map, or even blocking such paths altogether.

Proactive protection for vulnerable sites of ecological importance

These direct and indirect measures can prove effective in restricting numbers of visitors to sensitive areas in the countryside. Yet they may not be effective in handling sudden arrivals of crowds at specific sites. It is therefore essential to set up closed zones in sites of high ecological value. For example, at Mai Po Nature Reserve, visitors have to be guided by staff, so that crowds can be managed and educated at the same time. Core areas such as the bunds of gei wai, where waterbirds gather, and tidal the mudflats of Deep Bay are closed to visitors. This way, ecologically sensitive sites can be protected while allowing the public to appreciate nature.

Tour Guide is leading the public to visit Mai Po Nature Reserve
Visits to nature reserve should be led by tour guides.
© Henry Lui

The government should consider closing the more sensitive areas by cutting off the roads and trails, or erecting fences, or posting enforcement staff such as at Sham Wan on Lamma Island. On the other hand, public education is important, including for tour guides. Local villagers can help with protecting sites of ecological value. The government has in the past issued guidelines for dolphin watching activities in the western waters of Hong Kong, for visiting the Geopark. If participants and organisers can follow such guidelines, pressure on the countryside and wild species can be minimised.

From time to time, there is a burst of interest in a certain site. In recent years, photography fads on social media have attracted many people to the countryside. Fortunately, they are not going to ecologically vulnerable sites or sites with rare species. This is so far acceptable in ecological terms.

Most of the Hong Kong countryside is open to the public. The good thing is that people can visit for free at any time, and there is a minimum need for government to manage outings. Yet as traffic becomes more frequent and public interest gathers, there may be a heightened threat to the countryside.

Landuse planning is not comprehensive for protecting sites of ecological value. Active crowd control and ecological monitoring are needed, in addition to education and management. Hong Kong people have become used to going into the countryside as they wish. Perhaps we also need to change our mindset. A certain level of restriction at sites of ecological value can help safeguard a healthy and sustainable environment.