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Four facts to remember about Knysna”s wetlands:

• Wetlands are significant for the many ecosystem services they render. They act as a natural sponge against flooding and drought, and protect our coastlines (water quantity). They are a habitat for many animal species. The seagrass meadows around Leisure Isle, for example, support over 90% of the species occurring in the whole estuarine bay. The seagrass at Knysna also supports a number of high-profile rarities (besides the well-known seahorse) including various small snails and sea-slugs for which it is the only known place in Africa south of the Sahara where they occur.
• Wetlands play an important role in purifying water by “locking up” pollutants in their sediments, soils and vegetation. Some floating plants can even absorb and store heavy metals such as iron and copper. The natural ability of wetlands to filter and clean water has been used to treat wastewater from industry and mining – even sewage. Estuaries and their surrounding wetlands are also buffer zones. Coastal wetlands, such as coral reefs, mangroves, tidal flats, deltas and estuaries like ours, can limit the damaging effects of storm surges and tidal waves by acting as a physical barrier that reduces the water”s height and speed. Wetland vegetation such as saltmarshes can literally bind the shoreline together and reduce erosion from storms and freak tides.
• At least two-thirds of all the fish consumed worldwide are dependent on coastal wetlands,which provide spawning, nursery and feeding grounds. The Knysna Estuary is very important to South Africa”s fishing industry – it contributes 22% of the nation”s estuarine value to commercial fishing, and is the country”s most important nursery to line fish like red stumpnose, cob, white steenbras and spotted grunter.
• Estuaries are a combination of freshwater and saltwater whereas wetlands are found on the shores of estuaries and are characterized by salt marshes. The Knysna estuary has both and renders various ecosystem services including habitat protection, recreation, protecting coastal areas and citizens against floods. When it floods, estuaries act like huge sponges.

SANParks scientists have a registered project to identify and map all wetlands and associated rivers and tributaries flowing into the Knysna estuary. A product of this exercise will be an inventory of the exact location of wetlands. Knysna”s wetlands are not the same as traditional ones elsewhere in the country, they are found alongside rivers (Khayalethu, Bongani and Bigai).