|Central coordinates||14o 30.00' East 23o 20.00' South|
|IBA criteria||A1, A4i, A4iii|
|Year of IBA assessment||2001|
Site description Sandwich Harbour is a natural lagoon which lies on the Namib desert coast, c.55 km south of Walvis Bay. One of Namibia’s four Ramsar Sites, and the country’s only marine reserve, Sandwich was once a natural harbour for whalers and fish processors who could gain access to fresh water here. Owing to dynamic geomorphological change, its sandbars and lagoons shift constantly with winter storms and longshore currents.Two main sections of this wetland are recognized: the northern freshwater wetland, much reduced in size since the early 1970s when it covered c.2 km², and the southern mudflats, a 20 km² area of sand and mudflats inundated daily by the tides. The northern wetland is now a thin sliver, mainly of reedbed Phragmites, fed by a massive freshwater aquifer beneath the high dunes of the Namib sand-sea. This potable water slowly seeps through the wetland and there supports lush but dwindling stands of emergent and marginal vegetation. The wetland is protected from the Atlantic Ocean swells by a barrier beach which has moved from 1 km to within 100 m of the dunes. The southern lagoon, which leads into mudflats, is a relatively shallow water-body some 5 km long by 3 km wide. It is protected from the ocean by a western sand-spit that once reached the northern wetland but now joins the mainland some 3 km south of it.Sandwich Harbour is one of the most geomorphologically active areas along the entire Namib coast. In the late 1800s there was no barrier beach and therefore no protected wetland and an otherwise open harbour. The system continues to evolve rapidly and contrary to popular belief it is far from dead.
Key Biodiversity See Box for key species. This is the most important wetland for waterbirds in southern Africa, with counts exceeding 300,000 birds in some years. Sandwich Harbour regularly supports over 50,000 birds in summer and over 20,000 in winter. Traditionally, the northern wetland holds the highest species diversity (up to 51 species of wetland bird), while the southern mudflats hold by far the largest number of birds, dominated by terns, sandpipers, flamingos and cormorants. Shorebirds occur here at densities exceeding 7,000 birds/km², amongst the highest recorded in the world. The largest total counts at Sandwich Harbour have been 238,000 birds in January 1998 and 316,000 in January 2001.The area is vitally important for Palearctic waders and flamingos, which comprise the majority of the numbers. The area supports massive numbers of several species, including Phalacrocorax capensis, Phoenicopterus ruber and P. minor, Sterna hirundo, up to 40% of the world population of Charadrius pallidus, and tens of thousands of Calidris ferruginea and C. minuta. At times, the combined total of birds in Sandwich Harbour and Walvis Bay is so large that it constitutes half of all birds counted in southern Africa during African waterfowl counts.
Non-bird biodiversity: The dolphin Tursiops truncatus (DD) is seen in the lagoons, with pods of 10–20 animals not uncommon, while a non-breeding colony of c.10,000 Arctocephalus pusillus occupies the beach west of the mudflats. Hyaena brunnea (LR/nt) is a frequent visitor to the wetland.
|Species||Season||Period||Population estimate||Quality of estimate||IBA Criteria||IUCN Category|
|Greater Flamingo Phoenicopterus roseus||winter||-||2,480-11,900 individuals||-||A4i||Least Concern|
|Lesser Flamingo Phoeniconaias minor||winter||-||common||-||A1||Near Threatened|
|Cape Cormorant Phalacrocorax capensis||winter||-||4,230-25,300 individuals||-||A1, A4i||Endangered|
|African Oystercatcher Haematopus moquini||winter||-||20-90 individuals||-||A1, A4i||Near Threatened|
|Pied Avocet Recurvirostra avosetta||non-breeding||-||120-940 individuals||-||A4i||Least Concern|
|Chestnut-banded Plover Charadrius pallidus||non-breeding||-||170-5,590 individuals||-||A4i||Near Threatened|
|White-fronted Plover Charadrius marginatus||winter||-||440-2,540 individuals||-||A4i||Least Concern|
|Ruddy Turnstone Arenaria interpres||winter||-||402-2,260 individuals||-||A4i||Least Concern|
|Sanderling Calidris alba||winter||-||1,630-14,160 individuals||-||A4i||Least Concern|
|Little Stint Calidris minuta||winter||-||3,590-30,480 individuals||-||A4i||Least Concern|
|Curlew Sandpiper Calidris ferruginea||winter||-||3,580-43,680 individuals||-||A4i||Near Threatened|
|Kelp Gull Larus dominicanus||winter||-||280-3,200 individuals||-||A4i||Least Concern|
|Caspian Tern Hydroprogne caspia||non-breeding||-||30-168 individuals||-||A4i||Least Concern|
|Greater Crested Tern Thalasseus bergii||winter||-||80-820 individuals||-||A4i||Least Concern|
|Sandwich Tern Thalasseus sandvicensis||winter||-||200-3,660 individuals||-||A4i||Least Concern|
|Common Tern Sterna hirundo||winter||-||4,610-42,000 individuals||-||A4i||Least Concern|
|Damara Tern Sternula balaenarum||winter||-||50-300 individuals||-||A1, A4i||Near Threatened|
|A4iii Species group - waterbirds||winter||-||50,000-99,999 individuals||unknown||A4iii|
|2001||high||not assessed||not assessed|
|Good - based on reliable and complete / representative data|
|Human intrusions and disturbance||recreational activities||happening now||majority/most of area/population (50-90%)||slow but significant deterioration||high|
|Protected area||Designation||Area (ha)||Relationship with IBA||Overlap with IBA (ha)|
|Namib Naukluft||National Park||4,976,800||protected area contains site||8,500|
|Sandwich Harbour||Wetlands of International Importance (Ramsar)||16,500||protected area contains site||8,500|
|IUCN habitat||Habitat detail||Extent (% of site)|
|Land-use||Extent (% of site)|
|nature conservation and research||-|
References Berry and Berry (1975), Gebhardt (1973), Glassom and Branch (1997), Hellwig (1968), Kensley (1978), Kensley and Penrith (1977), Kinahan (1991), Lenssen et al. (1991), Noli-Peard and Williams (1991), Prozesky (1963), Simmons (1991, 1996b, 1999), Ward and Seely (1990), Whitelaw et al. (1978), Wilkinson et al. (1989).
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Recommended citation BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Sandwich Harbour. Downloaded from http://www.birdlife.org on 23/10/2016
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