Key Biodiversity Areas

Central Section of Bachang River (14292)
Taiwan, China, Asia

Site overview


KBA status: confirmed
Year of last assessment: 2001
National site name: Central Section of Bachang River
Central coordinates: Latitude: 23.4333, Longitude: 120.4167
System: freshwater, terrestrial
Area of KBA (km2): 3.15984
KBA classification: Regional
Legacy site: Yes

Site details


Site description: Extent of this site: mainly of the Bachang River channel, from upstream at the Junhui Bridge in Chiayi City downstream to the Provincial Highway 1. The northern shore is in the Hunei District of Chiayi City. The southern shore is between the Gongguan river section of Chungpu Village and the Yihsing section of Shuishang Village. The source of Bachang River is in the Fenchihu Mt. area of Chiayi County, and it flows through Chungpu and Chiayi City where the river slows, and great quantities of sediments settle out. In summer, torrential rains can suddenly swell the river, while in winter, the water level is smooth and shallow, and the water flows at a gentle speed. Therefore it forms an excellent environment for bloodworms to grow and multiply, serving as natural food sources for birds. Everywhere on the riverbanks grows clumps of Wild Sugarcane and Common Reed, young trees of India-charcoal Macaranga, Common Paper Mulberry, Taiwan Acacia, White Popinae and China Berry are slowly growing and maturing, supporting excellent refuge for the birds. In winter the water level in the channel is low, the undercutting activity on the riverbed forms sand walls which offer protection from the wind. For this reason, the Black-winged Stilts congregate on this section of river. This site is adjacent to the metropolis of Chiayi City, and forms one of the best spots for the citizens to get close to nature. Nevertheless, if there’s no proper planning and too many man-made facilities are constructed, loss of the ecological features of the river could be the result.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that was identified using previously established criteria and thresholds for the identification of Important Bird and Biodiversity Areas (IBAs) and for which available data indicate that it does not meet global KBA criteria and thresholds set out in the Global Standard.
Additional biodiversity: IBA criterion species: Black-winged Stilt: Time Feb. 1996 Nov. 1996 Mar. 1997 Dec. 1998 Jan. 1999 Oct. 1999 Jan. 2000 No. of bird 400 1645 145 407 646 460 324 • In 1996, the number of Black-winged Stilt here reached 1,645 birds which accounted for 80% of the wintering population for all of Taiwan; there are stable winter populations of 600-700 birds. Of the wintering birds, at least half are the chicks hatched in the same year, so this has large influence on this populations recruitment numbers. • At this site, 82 species have been recorded. Protected birds include Painted Snipe, Eastern Collared Pratincole, Grey-faced Buzzard Eagle, Osprey, Peregrine Falcon, and Brown Shrike. • Between May and July of both 1995 and 1996, Little Ringed Plovers bred on the high beaches of the sand flats. Later, however, excessive gravel extraction caused the sand dunes to disappear, and this year the birds were not seen breeding. Because floodwaters carry abundant sediments which settle out here, there is the possibility that the sand dunes will recover, supporting the Little Ringed Plover breeding habitat.

Habitats


Land use: agriculture (30%) | not utilised (1%) | urban/industrial/transport (1%) | water management (66%)
IUCN HabitatCoverage %Habitat detail
Artificial - Terrestrial50
Wetlands(Inland)50

Threats


Summary of threats to biodiversity at KBA: • Illegal mining of gravel caused the disappearance of the sand flats; and even though the sand flats increase in size between floods, in recent years, the Little Ringed Plover has not been recorded breeding here. • Wastewater from various sources had resulted in pollution of the river. • This is a tourist recreational area, since it is so close to Chiayi City. • There are natural disasters like typhoons and mud and rock flows. • The pressure from catching birds exists to the present; in winter, nets set up to capture birds are still regularly seen. Currently, only conservationists who patrol this area will pull these nets down. • The local government wants to develop a water park for the city residents, but this would create serious destruction and disturbance to the original habitats and ecosystems.

Additional information


References: • Wetlands Conservation Workgroup. 1994. 1994 Planning examples of environmentally sensitive areas at the coast of Taiwan- Investigations on bird, mangrove, and wetland. Environmental Protection Administration, Executive Yuan, Taiwan. • Weng, R. H. Personal unpublished data. • Wetlands Taiwan. Bird Database. • WBFT. Bird Database.