Call of the wild: managing HK’s newly-discovered bird species
The world’s foremost experts group on birds, the International Ornithologists’ Union, has just confirmed a new species of bird that was discovered on the mountain peaks of Hong Kong. Given the common name Chinese Grassbird, their estimated numbers are few (initial estimates suggests no more than 50-100 pairs in Hong Kong); therefore, the cause for conservation should be great.
It might be fortunate that the hill and mountaintop habitats where these birds make their home are largely found within Hong Kong’s country parks network. This, however, does not guarantee their protection. For within the country parks lies a more insidious threat to their existence.
Natural succession occurs when one type of vegetation colonizes another, such as when a forest habitat takes over a grassy meadow. For decades, efforts to reforest the barren, grassy hills of Hong Kong with introduced plant species (preferred for their fast-growing properties to stem erosion) has been assisted by natural succession. Government planners would have favored succession in their efforts to green the countryside.
Unchecked succession has continued today, where the vista of Hong Kong’s numerous hilly peaks appear to have partially returned to its former dense foliage of centuries past. This is bad news for the Chinese Grassbird, however, as their tall grassland habitats on the hills and mountains are being succeeded by forest vegetation, significantly reducing the supply of grassland habitat on which they depend.
A predicament for park managers then, is whether to allow succession to march on, because forests are a legitimate habitat for a range of other native species; or whether to restrain the vegetation transition. The former will see the population of Chinese Grassbird dwindle and impel their search for alternative grassy highlands; the latter can preserve existing habitats for a species unique to the hills of Hong Kong and surrounding region.
In order for park authorities to make a proper decision on how to conserve native species, they must be informed about its range and viability. They need to know about, for example, the life-cycle ecology of the Chinese Grassbirds, including its breeding and wintering preferences, food choice, and specificities like the thickness and height of grasses on which they favor. Decisions about protecting one habitat over another must not only consider the rarity of species therein, in comparison to other habitat sites, but also the likely change to a place’s ecology, as the Chinese Grassbirds’ reducing habitat shows.
Rethinking conservation management
Is it time, then, for Hong Kong’s conservation authority to rethink its response to natural succession? While succession-led reforestation was a welcomed mechanism, has it over-served its purpose in rural Hong Kong?
The right approach may be as elusive as acting on what we know, even when so little is known for certain. It means to progressively fill in the gaps of our understanding about grassland-dependent species and their requirements, with management on-the-ground working in tandem to stem the tide of biodiversity loss. Indeed, this is an approach that is gaining traction in park management circles worldwide.
Management of this kind will need to be flexible in adapting management solutions with newly-developed knowledge. It is this interplay between science and management, where new understanding can steadily inform management action, which makes this approach work. Changing ecological conditions, from the likes of succession or climate change, are amenable to this management approach.
This is an approach that is appropriate and urgently needed in Hong Kong. Recognizing the need for local implementation, Civic Exchange have captured some of the international best-practices and experience on adaptive management in a recent publication, assembling ideas on how it can be adopted for the governance of Hong Kong’s country parks.