Wuweigang is a marshy wetland that covers 108 hectares of land. Because river outlet is blocked by mud, it is called “Wuweigang,” meaning “a port without an outlet” in Chinese.Wuweigang is an important winter habitat for waterfowls in Taiwan because it is right in the middle of the autumn and winter birth migration path in this region and dwelled by lots of water species which the birds can eat.Every year, from November on, around 3,000 waterfowls or more gather up to spend their winter here. More than 170 species, 35 families of birds have appeared in this refuge, most of them waterbirds. But because there are lush forests in the nearby mountains, low-altitude mountain birds can also be seen.Eurasian teals are the largest in number, followed by spot-billed ducks and northern shovelers in Wuweigang. In the nearby paddy fields and fish ponds are snipes and plovers, and in forests and upland fields are ordinary land birds. At the Xingcheng River Outlet, rare transit birds and strayers are often found.