Mangrove ecosystems of the western and Gulf Provinces of Papua New Guinea, a review

Papua New Guinea (PNG) has mangrove areas of global significance, largely occurring on the south coast sedimentary lowlands between the Fly delta and the Gulf of Papua. These are the most taxonomically diverse mangroves to be found in the world. Several studies have shown mangroves of this coastline to be among the most productive in the world, with significant exports of mangrove carbon to sustain offshore foodchains. The figures available for mangrove areas indicate that there has been generally poor quality of assessments, with the exception of the Fly delta. More mangrove area assessments (inventory and mapping) are needed as a baseline for development of management plans. There are significant traditional uses of mangroves by coastal communities of southern PNG. Timber is used for house construction and tools, Nypa fronds for thatching and house walls, and mangrove is a popular firewood for cooking. Mangrove ecosystems are an important habitat for fish, crabs and clams that are gathered for food, as well as rare fauna such as dugongs, crocodiles, turtles, and a variety of waterbirds. There are a number of traditional medicines derived from mangrove species. There is evidence of over-exploitation and degradation of some areas of mangroves in southern PNG. Clearance of mangroves is generally followed by problems of coastal erosion. There is neither legislation that specifically protects mangrove ecosystems in PNG, nor protected areas that are established exclusively for mangrove conservation. Mangroves are a small component of two Wildlife Management Areas on the south coast. Mangrove management plans need to he developed, this is one of the actions of the Regional Wetlands Action Plan of the South Pacific Regional Environment Programme (SPREP).