Once famous for its whales, hence the name, Walvis Bay is a large modern town and Namibia’s only port. It is one of the country’s four Ramsar Sites and is located on the Kuiseb river delta, approximately halfway down the Namib desert coast, some 55 km north of Sandwich Harbour (NA014). The Kuiseb river no longer flows into its own delta, having been dammed off in 1962 to prevent flooding of the town. The wetlands south and west of the town make up the natural areas of Walvis Bay lagoon, and include intertidal mudflats and the eastern half of a 10-km-long north–south sand-spit called Pelican Point; this spit provides protection for the bay from Atlantic swells. A lagoon lies at the southern end of the open water. A salt-works was built at the southern end of this lagoon; it reduces the tidal sweep and possibly adds to increased siltation. Included in this IBA are the artificially flooded evaporation ponds of the saltworks, as well as the occasionally flooded areas to the south of the saltworks. The only terrestrial plants occur in the extensive riverine vegetation of the delta and the ephemeral river. The bay is a tourist attraction because of the proximity of 100,000 birds, mainly flamingos, to public areas. Rainfall is sporadic and averages about 15 mm per year, while precipitation in the form of coastal fog is common.
See Box for key species. In terms of numbers and species of birds, this is the most important coastal wetland in southern Africa, and is probably one of the three most important coastal wetlands in Africa. This area regularly supports over 100,000 birds in summer (maximum 162,000) and 50,000 in winter. Most birds (c.90% by number) which use the wetland in summer are non-breeding intra-African and Palearctic migrants. The area is vitally important for Palearctic waders and flamingos, which make up the majority of the numbers. Between 80–90% of the subregion’s flamingos winter here, utilizing especially the evaporation ponds of the saltworks, or at Sandwich Harbour (NA014). As many as 16 species occur in numbers exceeding 1% of the relevant biogeographical population.Several species number in their thousands, including Phoenicopterus ruber and P. minor, Calidris ferruginea, C. minuta, Sterna hirundo and S. paradisaea, and significant numbers of the global populations of Charadrius pallidus (60% of the world population) and Podiceps nigricollis occur. Other common species include Haematopus moquini, breeding Sterna balaenarum, Pluvialis squatarola, Charadrius marginatus, Arenaria interpres, Calidris alba, Recurvirostra avosetta, breeding Sterna caspia, S. bergii, S. sandvicensis and most of southern Africa’s Chlidonias niger. The site also holds large proportions of the southern African populations of Calidris canutus, Limosa lapponica, Numenius arquata and N. phaeopus. Smaller numbers of Pelecanus onocrotalus, Anas capensis and Charadrius hiaticula occur. This very high species richness and abundance is probably due to nutrients from the highly productive Lüderitz upwelling cell being brought north by the cold Benguela Current and being blown inshore by year-round winds.
Non-bird biodiversity: Whales, including Megaptera novaeangliae (VU) and Eubalaena australis (LR/cd), which once brought their calves into the sheltered waters, and were exterminated by early whalers, are still sometimes seen at sea. In recent years the rare cetacean Caperea marginata has occurred, while Lagenorhynchos obscurus (DD), Tursiops truncatus (DD) and the poorly known Benguela endemic Cephalorhynchus heavisidii (DD) are frequent visitors.
Pressure/threats to key biodiversity
Once an enclave of South Africa, Walvis Bay was ceded to Namibia in March 1994. However, the legislation in the Walvis Bay and Offshore Islands Act of 1994 made no provision for the gazetted Cape Nature Reserve to be re-promulgated, and other than its Ramsar status, it is not formally protected. However, moves by the recently formed Coastal Environmental Trust of Namibia, the Municipality and the Ministry of Environment and Tourism are making rapid progress towards improving the situation.Although the saltworks at Walvis Bay destroyed large areas of naturally flooded saltpan, it does provide large areas of permanently flooded shallow water with a range of salinities not naturally occurring in this environment. The artificial section of the wetland regularly supports more than half the birds in the wetland. Natural threats to the system include transport of wind-driven sand from the Kuiseb Delta into the lagoon, and the large silt load present in the ocean in and around the mouth of the lagoon, which may lead to the eventual siltation of part of the system. The growth of the Pelican Point sand-spit at 22 m per year decreases the tidal sweep during spring tides that once helped to scour the bay of wind-transported sand.Fish oils, fish-processing wastes and ship-borne pollution from the harbour have affected an already hyper-rich system, but most marine die-offs are associated with natural build-ups of sulphur dioxide precipitated by the high nutrient load of the waters. Oil spills from the natural gas fields off Lüderitz have the potential to be blown inland to Walvis Bay, but oil-spill contingency plans are in place.Light aircraft, prohibited from flying low over the lagoon and mudflats, regularly violate the height restrictions and disturb feeding birds, particularly flamingos. Implementing strictly enforced regulations, including the suspension of flying licences, may help curb this problem.
BirdLife International (2020) Important Bird Areas factsheet: Walvis Bay. Downloaded from
http://www.birdlife.org on 30/11/2020.