Located c. 190 km north of Durban, this site consists of the Richards Bay Game Reserve, which was formed when a berm wall was erected across Richards Bay estuary in 1976. The development of the harbour resulted in the division of the Richards Bay estuary into two sections by a 4-km-long causeway. To the north-east of the berm, unrestricted harbour and industrial development proceeded; the northern section consists of deep water holding clean-cargo berths and small-craft berths, an island known as Pelican Island and two breakwaters. To the south-west of the berm, the bay was left undisturbed as a nature reserve (or sanctuary area). Here, three rivers flow into the shallow mudflats and estuarine area. The Mtantatweni River drains Lake Cubhu, which lies to the south; an unnamed channel in the south-western corner of the sanctuary drains the sugar-cane lands on the floodplain; and the primary river, the Mhlatuze, forms the estuary. All the rivers are canalised. In feeding the southern lagoon, the Mhlatuze drains the largest section of the severely disturbed and modified Greater Mhlatuze Wetland System. It opens to the sea via an outlet that was created artificially at the time of the construction of Richards Bay harbour in 1976. In the dry season, the rivers almost cease flowing; in wetter times they carry considerable volumes of water into the bay. Flows naturally play an important part in keeping the new mouth of the sanctuary area open. The climate is subtropical and humid; average rainfall is 1 400 mm p.a., falling mostly in summer.
The once-extensive papyrus swamps on the Mhlatuze River floodplain have been largely drained and the land used for sugar-cane cultivation. The natural remnants in the Richards Bay area are fragmented and disturbed, and are surrounded by industrial sites, roads and dumps. Vegetation alongside the Richards Bay–Empangeni road consists of extensive stands of papyrus, with tall, dense, coarse grass and forbs at the edge. The substrate is flooded within the papyrus beds and the vegetation is very dense, making penetration almost impossible. Other sites in the area have Phragmites reeds or mixed emergent sedges, grass and bulrushes. The lagoon is tidal and very shallow, and is fringed by extensive stands of mangroves. It contains no palustrine wetland habitat of significance, except for some extensive Phragmites beds at its north-western end.
Salt-marsh communities have been, or are in the process of being, eliminated on the harbour side of the development. On the sanctuary side, salt-tolerant Phragmites reeds tend to dominate this niche. Most of the mangroves on the harbour side of the development have been killed or eradicated. Those that remain are becoming buried by silt. On the sanctuary side, the Rhizophora mangrove community represents the best surviving population in KwaZulu-Natal. A well-preserved remnant of climax coastal dune forest remains on the eastern side of the sanctuary area. On the harbour side of the development virtually no dune forest remains; instead, Casuarina plantations dominate the dunes. On the steep slopes, sand stabilisation has been successful. Savanna communities overlook the sanctuary from higher land near Lake Cubhu. Ilala palms are scattered throughout.
The sanctuary portion of Richards Bay holds more than 10 000 waterbirds. The wetland supports a complex community of water-associated birds that is seldom dominated by any particular species. The abundances of different species vary considerably as water levels and other conditions shift. The avifauna is diverse, largely as a result of the mosaic nature of the marginal vegetation along the water's edge, and the fact that several species reach the most southerly limit of their Afro-tropical distribution here.
Regionally threatened species are Pink-backed Pelican Pelecanus rufescens (1–35 individuals), Caspian Tern Sterna caspia (4–50 individuals), Mangrove Kingfisher Halcyon senegaloides, Great White Pelican Pelecanus onocrotalus (1–140 individuals) and Greater Flamingo Phoenicopterus roseus (1–97 individuals). Species that surpass the 0.5% population threshold are Little Tern Sterna albifrons (16–700 individuals) and Whiskered Tern Chlidonias hybrida (1–200 individuals).
The harbour, which was officially opened in 1976, was developed to serve the coal mines of the interior. EKZNW administers the reserve. Almost all the rivers that used to flow into the estuary have been canalised as land reclamation has proceeded.
The primary threat to the small area of estuary remaining in Richards Bay is the ever-increasing amount of sugar cane that is grown on the floodplain and the increasing levels of silt deposition in the sanctuary area; these threaten to change the dynamics of the estuary. Other threats to the system include inappropriate manipulation of the water level, and pollution, drainage and loss of habitats as a result of increased industrialisation. Richards Bay was once a very important nursery ground for many fish and invertebrate populations along the KwaZulu-Natal coast. This function has now mostly been lost. Various local extinction events are evident.
The IBA has been down-listed from a global to a sub-regional IBA because recent surveys indicate that the site may only occasionally surpass the 10 000 waterbird threshold. Historically, more than 20 000 waterbirds (qualifying the site for global IBA status) were regularly recorded, with up to 50 000 birds present during summer migrations. In addition, the nearby Thulazihleka Pan, which was previously included as part of the IBA, has now been excluded because it is heavily polluted and no longer supports significant numbers of waterbirds.
There is no doubt that, had there been no industrial development at Richards Bay, it would have been one of the finest wetlands for birds in Africa.
Richards Bay Game Reserve is a declared nature reserve administered by EKZNW.
Allan DG, McInnes A. 2002. Richards Bay waterbird survey January 2002. Technical report. Durban: Durban Natural Science Museum.
Allan DG, Sinclair JC, Rossouw J. 1999. The waterbirds of Durban Bay: current status and historical trends. Durban Museum. Novitates 24: 1–21.
Begg G. 1978. The estuaries of Natal. Technical report. Pietermaritzburg: Natal Town and Regional Planning Commission.
Cyrus DP. 1998. A review of the aquatic avifauna of the Mhlatuze Estuary. Southern African Journal of Aquatic Science 24: 130–140.
Cyrus DP. 2001. Aquatic avifauna of the coastal lakes of the Mhlathuze River system. Southern African Journal of Aquatic Sciences 26: 77–83.
Pretorius ML. 2012. A vegetation classification and description of five wetland systems and their respective zones in the Maputuland Coastal Plain. MSc Thesis, University of South Africa, Pretoria, South Africa.
Ryan PG, Cooper J, Hockey PAR, Berruti A. 1986. Waders (Charadrii) and other water birds on the coastal and adjacent wetlands of Natal, 1980–1981. Lammergeyer 36: 1–33.
Taylor MR, Allan DG. 2013. Avifaunal assessment of the Umhlatuze estuary system, KwaZulu-Natal, South Africa. Technical report. Johannesburg: BirdLife South Africa.
Turpie JK. 1995. Prioritizing South African estuaries for conservation: A practical example using waterbirds. Biological Conservation 74: 175–185.