Project Title: Population Dynamics and Ecology of Water Buffalo in Pui O, Lantau

Applicant: The Lantau Buffalo Association Limited

Total Approved Grant: $54,934.00

Duration: December 2004 to May 2005

Project Status/Remarks: Completed

Scope:
The objectives of this study are:

a. To identify plants consumed by the water buffaloes.

b. To identify herd composition and to identify distinguishable individuals.

c. To determine activity period, behavior and habitat usage by water buffaloes during dry and wet seasons.

d. To determine habitat preference and requirement by the water buffaloes.

e. To estimate optimum sustainable number of buffaloes.

f. To enhance awareness of the ecological importance of water buffalo in Pui O.

Summary of the Findings/Outcomes:

The main findings of the ecological study were that there were two main herds in Pui O - a mixed herd and a bachelor herd.  At the end of the study, the mixed herd consisted of 15 or 16 1st year individuals, eight 2nd year individuals, fifteen 3rd year juveniles and nineteen adult females in Pui O wetlands.  The bachelor herd consisted of 12 bachelor males.  The Pui O buffaloes appear to spend majority of their time grazing and ruminating during the daylight hours irrespective of season.  Both the mixed and the bachelor herd spent most of their time in the main wetland / open grassland areas.  Grass was the preferred food of the buffaloes although some browsing of trees, vines and macrophyte plants growing in the wetland/grassland areas was present during the drier times of the year (winter and spring seasons).

Overall the study found that in comparison to the summer season, during the winter and spring seasons there is greater sharing of wetland/open grassland area by the mixed and bachelor herd, reduced wallowing time, foraging of a wider area and greater frequency of village visits.

Another important result of this study was the quantifying of the high population increase in Pui O and the high density of buffaloes for the wetlands in Pui O.  The instantaneous population growth rate of water buffaloes in Pui O area was found to be 0.0953 and the population density of buffaloes was calculated to be 2.8 buffaloes per hectare or 277 buffaloes per km2.  It is suggested that the population density of buffaloes in Pui O be reduced to 1 or 1.2 buffaloes per hectare or a total population of 20-24 buffaloes.  This requires active participation of AFCD in control of the buffalo population and recommendations for which buffaloes need to be targeted have been made in the report.

Wetlands are treasured for a number of ecosystem services that they provide humans such as flood control, shoreline stabilization, water purification, etc (Ramsar Convention on Wetlands 2002).  Wetlands are the only ecosystem in the world that are protected by their own convention, the Ramsar Convention.  Mai Po is an example of such a wetland in Hong Kong.  Mai Po is of course important as a stopping point for migratory birds, including the endangered black-faced spoonbills.  Pui O is an important wetland area that is reminiscent of the paddy fields and farming way of life of farmers 30-40 years ago.  The water buffaloes are an integral part of that cultural history.

Pui O is also important for its biodiversity of wetland plants and macroinvertebrates.  This area and the free-roaming water buffaloes can be utilized as a tourist destination.  Pui O can be an important educational resource for teaching kids and visitors about the history of Hong Kong and about wetland flora and fauna and adaptation of these organisms to this special environment.  Protection of Pui O is especially critical considering reports of developments planned for the area (South China Morning Post, 5 March 2004; Lantau Development Task Force http://www.pland.gov.hk/lantau/en/background/index.html).

China plans to increase the number of wetlands under protection from 40% to 60% by 2010 signifying the realization of the ecological and economic importance of wetlands by the Chinese government (South China Morning Post, 29 June 2004).  With the increasing awareness of the importance of protecting wetlands in China (Global Environmental Facility subsidized project on Wetland Biodiversity Conservation and Sustainable Use in China, 2000-2004; http://www.chinabiodiversity.com/china-news/gef-en.htm), Hong Kong should follow suit.