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Wildlife of the Gambia is dictated by several habitat zones over its total land area of about 10,000 km2. It is bound in the south by the savanna and on the north by the Sudanian woodlands. The habitats host abundant indigenous plants and animals, in addition to migrant species and newly planted species. They vary widely and consist of the marine system, coastal zone, estuary with mangrove vegetation coupled with Banto Faros (barren hypersaline flats), river banks with brackish and fresh water zones, swamps covered with forests and many wetlands.〔Penney, pp. 5–7〕 According to the Government of the Gambia, about 3.8% of the land area of the country has been brought under national parks or reserves, and the present wildlife policy is to extend this coverage to 5%. The seven areas included in the protected list are the Niumi National Park, Kiang West National Park, River Gambia National Park, Bao Bolong Wetland Reserve, Abuko Nature Reserve, Tanbi Wetland Complex and the Tanji Karinti River Bird Reserve. These are managed by the Department of Parks and Wildlife Management. The area covered by these parks is 38,000 ha.〔(【引用サイトリンク】title=National Parks & Nature Reserves in Gambia )〕 The birdlife in the Gambia is colourful and rich, with 560 species inhabiting coastal saltwater, freshwater wetlands, Guinea and Sudan savanna, woodlands and forests, agricultural lands, towns and villages.〔Emms, pp. 25–28, 44–48〕 It is thus a biodiversity hot spot for ornithologists. ==Geography== The flat terrain of the Gambia, drained by the Gambia River is categorised under several habitat types. The habitat types are the coast, mangroves and Banto Faros, wetlands, farmlands, savanna and the Sahel habitats, gallery forests and urban habitats.〔 The coast extends to into the sea with extensive sea green grass meadows where aqua fauna dominate; the long stretch of beach here, with occasional hills or cliffs, is topped with plants which are salt tolerant and bind the terrain. Above these are the very old beaches at an elevation where the rich vegetation consists of baobab ''(Adansonia digitata'') and ron palm ''(Borassus aethiopum)'' species interspersed with shrubs and grassland. The sea grass meadows of the coastal areas are rich in green sea turtles ''(Chelonia mydas)'', dolphins, common minke whales ''(Balaenoptera acutorostrata)'' and Mediterranean monk seals ''(Monachus monachus)'', which feed on the fish species.〔Emms, pp. 25–28〕 Mangroves and Banto Faros are the mangrove swamp forests seen at the mouth of the Gambia River and extending along the river inland up to Kaur, into the brackish river stretch.〔〔 It is a transitional zone between aquatic and terrestrial habitats. Two types of mangrove forests, namely the white mangrove colonies and the red mangroves, are of short height near the coast but raise to 15–20 m in the upstream stretches of the river. Banto Faros are found, after the mangroves, in flat lands which are barren and salt encrusted; however, succulent plants grow in some of the less saline thick mats. Fishes spawn in the mangroves before they move offshore in to the sea. Mangrove oysters, (''Crassostrea gasar'' and ''Crassostrea tulipa'') are also extensively found on mangrove trees in this habitat, which are collected and used as firewood and also as building material.〔 Wetlands consist of salt pans, lagoons, marshes, mangrove swamps, mudflats, saltwater rivers, fresh water reaches of rivers such as the Gambia River, flooded sand mines, watering holes for animals, paddy fields and ephemeral marshes with reed vegetation in flooded areas. Crustaceans, annelid worms and molluscs are the fauna in the wetlands where migrant birds and wading birds find their feed.〔 Farmlands, including savanna and woodland, form now a dominant habitat in the Gambia where crops were grown initially on a rotation system of 20 years with a fallow period. This practice has since changed to two or three years rotation. While the agricultural crops grown are sorghum, millet and ground nuts, the tree species retained, within the lands cleared for agricultural use, are the ''acacia albida'', baobab, ficus species, winterthorn and African locust ''(Parkia biglobosa)''.〔 Savanna and the Sahel habitats are of two types. One is the southern Guinea savanna which has rich and dense vegetation of over 50 tree species. The other is the Sudan Savanna which is contiguous to the Guinea savanna on the north bank of the Gambia River. These areas are dry woodlands with soils of laterite formations. The local tree species include silk cotton ''(Bombax costatum)'', dry-zone mahogany ''(Khaya Senagalensis)'' in deeper soil areas and African rosewood ''(Guibourtia coleosperma)''. Short grasses and shrubs are seen thinly spread in the Sahelian habitats.〔 The gallery forests (moisture forests), unlike the rainforest, thrive on groundwater and are integral to savannas. It is a rare habitat found only in Abuko Nature Reserve, Pirang Forest Park and in some stretches of the Gambia River with different set of species with some degree of overlap with rainforests.〔 Urban habitat consists of numerous villages. The open areas in between have large green stretches with profusion of tree species, particularly the mango ''(Mangifera indica)'' trees.〔 Law of the land Some parts of the land area of the Gambia, under the protection laws of the Banjul Declaration of 1977, which is the law on wild life, includes seven protected zones of the country. The law prohibits all types of hunting, except on animals harmful to the environment, such as warthog, giant pouched rat and francolin. Also, as a signatory to the International Trade in Endangered Species of Flora and Fauna (CITES), the Gambia enforces law prohibiting export or even possession within the country of any animal skins, horns or turtle shells. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wildlife of the Gambia」の詳細全文を読む スポンサード リンク
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