Industry alongside mangrove and tidal wetlands in the Port Curtis area, Queensland.
Fishing in Pumicestone Passage, Queensland.
Australia’s mangroves suffer unfairly from a bad image. This is compounded by the often destructive practices associated with unlawful access, the refuse dumped on them, and the inadvertent damaging alterations to hydrology and drainage. Mangroves and tidal wetlands are often viewed as wastelands, as breeding grounds for mosquitos, as smelly and distasteful places, and as landfill sites for the creation of desirable land for coastal services and urban living. But, notwithstanding such views, there are many who are beginning to appreciate the numerous tangible and intangible benefits provided by mangroves.
Benefits of Mangroves
Australia’s mangroves have a broad range of benefits based on their primary and secondary production, as well as their woody biomass and forested structure. The benefits of mangroves include:- fishery products of both estuarine and coastal fishes, crustaceans and molluscs; shoreline protection based on mangrove tree and root structures in reducing erosion, and providing stand protection from waves and water movement; nutrient uptake, fixation, trapping and turnover; carbon sink and sequestration; secondary production via grazing and decomposition of mangrove plants plus associated microbial and faunal production; sediment trapping based on mangroves being a depositional site for both water and airborne sediments that help reduce turbidity of coastal waters; a habitat for specialised fauna; a nursery habitat; food resources for animals such as migratory birds and fish; occasional forest products like timber and firewood; and, visual amenity where selected mangrove trees provide shoreline beautification.
- Using mangroves as a trimmed hedge garden setting along the Nerang River, Queensland.
- Enjoying a beautiful day at Mangrove Cove, Leschenault Inlet, Western Australia. photo: Diana Kleine
Australia’s mangroves provide important nursery and habitat for important commercial fish and prawns. More than 90% of Australians eat seafood and domestic consumption continues to grow. It has been estimated that the contribution of mangrove-related species in eastern Australia is around 67% of the entire commercial catch.
Australia’s mangroves play an important role in controlling erosion and protecting coastlines. In tropical northern regions, mangroves provide a protective buffer from severe cyclones and storms that periodically lash the northern tropical coast.
Altered Value versus Natural Benefits
Mangroves are highly valued for some benefits, such as their importance for fish biomass and diversity plus coastal protection. However, mangrove areas have been steadily removed from the more populated northern estuaries over the last 150 years. These practices indicate how mangroves and tidal wetlands have been valued more for their conversion to other land-uses than for their collective benefits as a healthy natural habitat.
- A stingray shelters amongst Rhizophora roots, Schnapper Island, Queensland.
- Throwing a caste net for bait in Theodilite Creek, Queensland.