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Djoudj National Bird Sanctuary
In the Senegal River delta, the Djoudj Sanctuary is a wetland of 16,000 hectares, comprised of a large lake surrounded by streams, ponds and backwaters, which form a living but fragile sanctuary for one and a half million birds, such as the white pelican, the purple heron, the African spoonbill, the great egret and the cormorant.Threats to the Site:ituated in the Senegal river delta, the Djoudj Sanctuary is a wetland of 16,000 ha, comprising a large lake surrounded by streams, ponds and backwaters. It forms a living but fragile sanctuary for some 1.5 million birds, such as the white pelican, the purple heron, the African spoonbill, the great egret and the cormorant.
PHYSICAL FEATURES The park is in a vast basin of impermeable holomorphic soils forming saline flats in the Senegal River delta between the main channel to the north, the Djoudj bayou and the Gorom, or bayou to the south. This delta, of which Djoudj is a small part, has been subject to flooding and to the development of dyke systems for many years, the latest in 1963. These dykes have allowed fresh water to be retained in the Djoudj basin for longer periods than normal, benefiting the waterbirds. Salinity varies, from nearly fresh during winter inundations to brackish as the water levels fall.
CLIMATE Sahelian with alternate wet and dry seasons. Mean annual precipitation is 300mm and mean annual temperature 27°C. During the dry season, it is the wettest area in the region, but in recent years rainfall has been less than one fifth of the average and Djoudj has been much drier.
VEGETATION Vegetation reflects a low rainfall on unfavourable holomorphic soils. The Sahelien type savanna is dominated by spiny bushes, acacias such as Acacia nilotica, A.tortilis, A. seyal, tamarisk Tamarix senegalensis, and Balanites aegyptiaca. During the rains dense populations of Typha spp. and waterlily Nymphaea spp. appear in the flooded zones. Halophytic plants, particularly Salicornia spp., cover much of the area. Aquatic vegetation is dominated by Pistia stratoites.
FAUNA The area is particularly noted as a stopover for a large number of birds. From September to April, an estimated three million migrants pass through, including garganey Anas querquedula, shoveler Anas clypeata, pintail A. acuta, ruff Philomachus pugnax, and black-tailed godwit Limosa limosa. Thousands of flamingo Phoenicopterus ruber can be found here. About 5,000 white pelican Pelecanus onocrotalus nest here regularly, as well as white-faced tree duck Dendrocygna viduata, fulvus tree duck D. bicolor, spur-winged goose Plectropterus gambensis, purple heron Ardea purpurea, night heron Nycticorax nycticorax, various egrets Egretta spp., spoonbill Platalea leucorodia, African darter Anhinga rufa, common cormorant Phalacrocorax carbo, white-breasted cormorant P. lucidus and Sudan bustard Otis arabs. Mammals include warthog Phacochoerus aethiopicus and African manatee Trichechus senegalensis (V), and several species of crocodile and gazelle have been successfully reintroduced into the area.
VISITORS AND VISITOR FACILITIES More than 5,000 tourists visit the park each year. One camp is open from mid-November to mid-April (construction of a second on the north-east border is planned) and there are hotels in St Louis nearby. There are a dozen bird observation points on the borders of the most important waterbodies. Canoes can be hired. A small eco-museum has been constructed by the St Louis Club Jeunes-Nature.
SCIENTIFIC RESEARCH AND FACILITIES Research includes rodent studies, bird ringing to investigate migration routes, and population dynamics. ORSTOM has sponsored research in this area since 1955. Studies of waders were carried out in 1983-1984 by Station Biologique de la Tour du Valat, France. An expedition to catch and ring palaearctic migrants was undertaken in 1990, for which some 3,300 birds of over 70 species were ringed (Beecroft, 1991). There is an observation hut.
CONSERVATION VALUE The park was mainly established as the area is so important for birds, supporting three million waterfowl, and is one of the main West African sanctuaries for Palaearctic migrants. It is one of the first fresh water sources they reach after crossing 200km of the Sahara.
CONSERVATION MANAGEMENT Wardens are stationed in five watch posts, one in the centre and four on the boundaries. Various administration zones are co-ordinated by a ranger. The park is closed three months of the year for park management. A dyke has been built right around the park as well as a dam system so that water levels will not be affected by the alternating flow of the River Senegal after the barrages have been built. With the operation of the Diama salt barrage in the Senegal River, the water supply for Djoudj is now much more secure than at any time in the past. However, because of the corroded condition of the sluice gates on the Djoudj marigot, one of the two water inlets into the park, staff are unableto control water levels which are largely determined by levels in the Diama reservoir (Dugan, pers. comm., 1987).
MANAGEMENT CONSTRAINTS Rainfall has been too low in the past few years for water levels to be normal. The Compagnie Sucrière Sénégalaise built a temporary dam just upstream of Djoudj at Kheune to prevent salt water flowing up the Senegal River in the dry season. This had the effect of reducing the supply of fresh water to Djoudj. The river's 1984 flood swept this away and Djoudj was replenished normally. In the 1984/1985 dry season, Djoudj was connected by canal with fresh water above the Kheune barrage in an attempt to stop it drying out. Water supply in this region is a problem, and permanent dams are being built to regulate the flow of the Senegal River. Completion of the dam of Diama in 1986 would improve water supply for Djoudj although the effects of another dam at Monatali in Mali (expected 1984) are as yet unknown. However, the habitats at Djoudj are adapted to changing water levels, which may be altered by these dams. Djoudj was put on the World Heritage in Danger list because of this threat (Thorsell 1985) but was removed from the list in 1988.
STAFF A total of 21 rangers and one conservator (National Park Office, pers. comm., 1995).
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posted to World Heritage Sites. at Thu Nov 06 14:05:44 EST 2003.
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