[1] The original St Lucia and Maputaland MPAs were proclaimed in the 1970s to protect the coral reefs and the beaches where loggerhead and leatherback turtles make their nests.

The Maputaland MPA, which forms part of iSimangaliso Wetland Park, extended a distance of 3 nautical miles (5.6 km; 3.5 mi) seawards from the coast between the Mozambique border and Gobey's Point near Lake Sibhayi.

[7] This subtropical area includes forests dotted with lakes and swamps, as well as coral reefs and deserted beaches.

[10] The offshore extension is intended for the protection of deep water ecosystems and to secure the habitat and foraging areas of endangered Leatherback turtles and coelacanths.

This includes the canyons and the known coelacanth population, and cold-water corals, and breeding areas for turtle species.

[11] Th length of coast is increased to 220 km and surface area to 13 289 km2 The boundaries of the MPA are:[1] The Maputaland and St Lucia Marine Reserves form a continuous protected area stretching 150 km from the Mozambique border to Cape Vidal for 3 nautical miles out to sea.

The shoreline is mostly sandy beach with a few outcrops of more resistant rock forming occasional headlands, as at Jesser Point.

The seabed of the shelf is largely covered by sand and coarse, shelly sediment, with patches of coral reef.

[14] The southward-flowing Agulhas Current has a strong influence on the oceanic and coastal environment of the MPA, as it brings warm waters from the tropics along the edge of the continental shelf, which is close inshore and relatively shallow, however, there is a net northward longshore transport of sediment along the coast.

iSimangaliso protects the southernmost extent of coral reefs in Africa, long sandy beaches, and deep submarine canyons.

To the south, the Natal Sub-province of the Sub-tropical East Coast Province extends to Cape St Lucia, and supports many endemic species.

[18] Sedimentary bottoms at first glance appear to be fairly barren areas, as they lack the stability to support many of the spectacular reef based species, and the variety of large organisms is relatively low.

The sediment is continually being moved around by wave action, to a greater or lesser degree depending on weather conditions and exposure of the area.

This means that sessile organisms must be specifically adapted to areas of relatively loose substrate to thrive in them, and the variety of species found on a sandy or gravel bottom will depend on all these factors.

Sedimentary bottoms have one important compensation for their instability, animals can burrow into the sediment and move up and down within its layers, which can provide feeding opportunities and protection from predation.

These occasionally deflect deeper, colder, water to the shallower reef areas, where it mixes with the upper layers and has an overall cooling effect, which is thought may affect susceptibility to coral bleaching.

As this was the first time such bleaching had been observed in this area, there is little data available on the environmental stress, resistance, adaptation and community changes of these reefs, and a long term monitoring project has been started.