The Orange Shelf Edge Marine Protected Area is an offshore conservation region near the edge of the continental shelf in the exclusive economic zone of South Africa off the north coast of the Northern Cape province.
History
The MPA protects an area of seabed that according to records has never been trawled.
Purpose
A marine protected area is defined by the IUCN as "A clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values".
Extent
The MPA is off the Northern Cape in the depth region of the continental slope, about 95 nautical miles northwest of Port Nolloth, and comprises three separate areas. The protected areas include the water column, sea bed and subsoil inside the boundaries. Two of the areas have their northwestern boundary on the boundary between the EEZ of South Africa and the EEZ of Namibia. The protected area of ocean is about .
Boundaries
Orange Shelf Edge area 1 is bounded by: Eastern boundary: A S29°43.56′ E14°51.9′ to B S29°49.98′ E14°51.9′ Southern boundary: B S29°49.98′ E14°51.9′ to C S29°49.98′ E14°40.98′ North-western boundary: C S29°49.98′ E14°40.98′ to A S29°43.56′ E14°51.9′
Orange Shelf Edge area 2 is bounded by: Northern boundary: A S29°40.000′ E15°0.000′ to B S29°40.000′ E15°10.000′ Eastern boundary: B S29°40.000′ E15°10.000′ to C S30°10.000′ E15°10.000′ Southern boundary: C S30°10.000′ E15°10.000′ to D S30°10.000′ E15°0.000′ Western boundary: D S30°10.000′ E15°0.000′ to D S30°10.000′ E15°0.000′
Orange Shelf Edge area 3 is bounded by: Northern boundary: A S30°0.06′ E14°24.18′ to B S30°0.06′ E14°50.1′ Eastern boundary: B S30°0.06′ E14°50.1′ to C S30°10.02′ E14°50.1′ Southern boundary: C S30°10.02′ E14°50.1′ to D S30°10.02′ E14°8.22′ Western boundary: D S30°10.02′ E14°8.22′ to A S30°0.06′ E14°24.18′
Zonation
The whole of the MPA is zoned as a sanctuary area.
Management
The marine protected areas of South Africa are the responsibility of the national government, which has management agreements with a variety of MPA management authorities.
The Department of Agriculture, Forestry and Fisheries is responsible for issuing permits, quotas and law enforcement.
Use
Geography
Climate
Seasonal variations in sea conditions
Ecology
The MPA is in the cool temperate Benguela ecoregion to the west of Cape Point which extends northwards to the Orange River. There may be species endemic to South Africa in this region.
Three major habitats exist in the sea in this region, two of them distinguished by the nature of the substrate. The substrate, or base material, is important in that it provides a base to which an organism can anchor itself, which is vitally important for those organisms which need to stay in one particular kind of place. Rocky shores and reefs provide a firm fixed substrate for the attachment of plants and animals. Sandy beaches and bottoms are a relatively unstable substrate and cannot anchor kelp or many of the other benthic organisms. Finally there is open water, above the substrate and clear of the kelp forest, where the organisms must drift or swim. Mixed habitats are also frequently found, which are a combination of those mentioned above. There are no significant estuarine habitats in the MPA.
Rocky reefs
There are rocky reefs and mixed rocky and sandy bottoms. For many marine organisms the substrate is another type of marine organism, and it is common for several layers to co-exist.
The type of rock of the reef is of some importance, as it influences the range of possibilities for the local topography, which in turn influences the range of habitats provided, and therefore the diversity of inhabitants. Sandstone and other sedimentary rocks erode and weather very differently, and depending on the direction of dip and strike, and steepness of the dip, may produce reefs which are relatively flat to very high profile and full of small crevices. These features may be at varying angles to the shoreline and wave fronts. There are fewer large holes, tunnels and crevices in sandstone reefs, but often many deep but low near-horizontal crevices.