UNESCO/Toson-Khulstai Biosphere Reserve
Lake Chilwa Wetland
General information
Situated in the south of Malawi close to the eastern border with Mozambique, the Lake Chilwa Wetland Biosphere Reserve is home to one of the world’s most diverse populations of bird species. Lake Chilwa is the second largest lake in Malawi and was formed by tectonic processes. It encompasses an area of approximately 240,000 ha and the water level rises up to 627 metres above sea level. The lake functions as a shallow inland drainage basin; its eastern side is composed of sandy soils, while the remaining soils comprise fine-grained clays. Altogether, the Chilwa plain consists of seven agro-ecological zones defined by different soil groups. In addition, the reserve’s topography includes the Chilwa plains, open lake waters and mountainous areas such as Mount Zomba and Mount Mulanje. In 1997, the wetlands of the Biosphere Reserve were designated a Ramsar site due to their global significance as a major waterfowl habitat.
Detailed information
Key data
Year of nomination
2006
Country
Malawi
Total population
993447
Area
Surface
614,182.00 ha
Total terresterial area
614,182.00 ha
Location
Latitiude: -15.3464 - Longitude: 35.6618
Ecological Characteristics
The Lake Chilwa Wetland Biosphere Reserve lies within the tropical dry or deciduous forest biogeographical region. Different land cover types are distributed throughout the reserve, including marshes, swamps, open lakes, five major rivers, islands, cultivated floodplains and grasslands. Lake Chilwa is a tropical, closed lake. Under usual circumstances one-third of the lake consists of open water, one-third of marshes and one-third of floodplains. However, this distribution varies according to the season. Dry seasons (May–October) and wet seasons (November–April) lead to seasonal fluctuations of the water level of up to one metre. Within the last century the lake has dried and filled up eight times.Forests within and surrounding the reserve are some of the oldest in all of Malawi.Typhaswamps cover wetland areas and serve as habitats and food providers for numerous species; they are equally important for nutrient cycling. Overall, the Mulanje has 35 endemic species. However, seasonal burnings of vegetation for hunting purposes endanger many particularly vulnerable species. Examples of common fauna species that live in the reserve arePelecanus rufescens(Pink-backed pelican),Python sebae(Python) andAlestes imberi(Spot-Tail Tetra).Zonocerus elegans(Elegant grasshoppers) andPelomys fallax(Creek rats) are frequently consumed species. The Lake Chilwa Wetland Biosphere Reserve is also rich in bird species with 164 species living within the reserve and 41 Palaearctic and 14 intra-African migrant species seasonally inhabiting the area.
Socio-Economics Characteristics
The Lake Chilwa Wetland Biosphere Reserve faces high population pressures with 77,000 people living in the transition zone and 916,447 in the entire Lake Chilwa basin. The nearest major towns are Machinga, Phalombe and Zomba. The principle economic activities, such as rice farming, fishing, bird hunting and livestock rearing, take place within the transition area. Within the core and buffer zone economic activities are limited to fishing, and transportation is permitted only via canoes or small-engine boats. The fishery yields 25,000 tonnes of fish each year, while fuel wood is used for the fish-smoking industry (6,500 tonnes of wood per year).The dominant tribal group in the Lake Chilwa Wetland Biosphere Reserve is the Yao. Other aboriginal groups include the Chewa and Nyanja, among others. The catching of fish has a traditional and cultural importance for the local population – the higher the amount of caught fish, the higher the chances of receiving good luck. Fish are also used as sacrifices and medicinal resources. During school holidays, the Yao celebrate certain ceremonies and perform Manganje dances. The Yao had a strong connection with the Sena people, who used to live permanently in the area until the Chilwa Lake dried out during several seasons. They are renowned for introducing dowries into marriage (Lobola). In 1995, Lake Chilwa and its wetlands dried up completely resulting in severe starvation among local people. This highlights the importance of Lake Chilwa as a vital resource for survival.