Mai Po Inner Deep Bay is an important Ramsar Site, with a large aggregate of wetland birds during the spring and autumn migration, while many remain during winter, and some are resident here (altogether in the range of 100,000-150,000). The Hong Kong Bird Watching Society (HKBWS) initiated the monitoring of wintering waterbirds in 1979, which was before the designation of the Ramsar Site. It was expanded to monthly waterbird monitoring with funding support from the Agriculture, Fisheries and Conservation Department (AFCD) in the 1990s. Voluntary surveyors from Hong Kong and Shenzhen conduct synchronized counts around high tide, covering intertidal mudflats, fish ponds, shrimp ponds (gei wais), stream and channels. The Waterbird Monitoring Programme provides useful information on the waterbird population in the Deep Bay wetlands and affirms the importance of Deep Bay wetlands and wetland conservation in the area.