Fishpond Functions
Fishponds not only support fish farming and provide a source of food, but also offer many other important values and functions. Fishponds exemplify a unique scene of “harmony between humans and nature”.
Ecological Values and Important Habitats for Waterbirds
The environment and operations of fishponds provides foraging and roosting habitats for waterbirds. Hong Kong lies along the “East Asian–Australasian Flyway”. More than 50,000 migratory birds pass through Hong Kong every year. When the fishpond operators lower the water level to harvest fish, these shallow fishponds attracts waterbirds to feed on fish of lower economic value and invertebrates. Fishponds not only provide food for resident birds, but also are important food supply for passage migrants and winter migratory birds.
Around 1,500 hectares of fishponds and wetlands in the Mai Po Inner Deep Bay area, including Mai Po, Tai Sang Wai and Lut Chau, were designated as a Wetland of International Importance under the Ramsar Convention in 1995, recognising their significant ecological value.
Besides, fishponds possesses rich biodiversity. Apart from birds, the vegetated pond bunds also provide habitats and breeding grounds for amphibians, reptiles, mammals and a wide variety of insects, such as dragonflies and fireflies.
Flood Mitigation and Stormwater Storage
Large fishponds have excellent water storage capacity and can temporarily hold floodwater caused by heavy rain during the rainy season, thereby helping to store water and reduce flooding.
Microclimate Regulation
Fishponds are able to store large volumes of water, which absorb heat and evaporate from the water surface. This helps reduce the temperature difference between day and night and makes the local microclimate more stable.