If you wish to provide feedback on the revised environmental ask for inclusion of this EBSA into the upcoming Marine Spatial Planning process, please fill in the survey form

Data used in the analyses below (ecological condition, threat status, protection, distribution of activities, cumulative pressure from activities) are from the National Biodiversity Assessment 2018: Marine Realm Assessment. See the NBA 2018 website for access to the report.


EBSA Status Assessment and Management Recommendations

Ecological Condition, Threat Status, Current Protection and Key Features in the EBSA

Relevant Pressures and Activities (impact, extent) | Management Interventions Needed for the EBSA

Activity Evaluation Per Zone: Zoning Feasibility | Back to the SA EBSA status and management home page



EBSA overview

Shackleton Seamount Complex contains the Mallory, Shackleton and Natal Seamounts, which support fragile, sensitive species. The EBSA extends to the outer edge of South Africa’s EEZ and so it’s relatively remote and largely still in a natural condition. Productivity is high from sporadic shelf-edge upwelling, and it is also a spawning area for sardine, anchovy, horse mackerel and hake. Diversity is relatively high at this site too.

Click here for the full EBSA description


Ecological Condition, Threat Status, Current Protection and Key Features in the EBSA

Shackleton Seamount Complex has a several seamounts that need to be protected for the area to maintain the features and processes that give it its EBSA status. The criteria for which this EBSA ranks highly are: importance for life history stages, vulnerability and sensitivity, biological productivity, biological diversity, and naturalness. There are eight ecosystem types represented, which is relatively high for an area this far offshore. Many of these ecosystem types contain fragile species that are especially sensitive to damage, particularly the seamounts. The site is also recognised as a spawning area for sardine, anchovy, horse mackerel and hake.

Shackleton Seamount Complex proportion of area in each ecological condition category.


Shackleton Seamount Complex is largely in good ecological condition (76%), with most of the remaining area in fair ecological condition (24%) and a fraction (<1%) that is in poor ecological condition. Consequently, whole EBSA is Least Concern (100%).


 Shackleton Seamount Complex proportion of area in each ecosystem threat status category.


Shackleton Seamount Complex proportion of area in a Marine Protected Area (MPA).


Protection of features in MPAs has been considerably expanded and strengthened following the proclamation of the Operation Phakisa MPA network, with the EBSA area within reserves increasing from no protection to 41% protected. These new MPAs cover the Natal seamount, but not Mallory or Shackleton Seamounts in the middle of the EBSA. There are also still some ecosystem types within the EBSA that are poorly or not protected.


Threat status, protection level and ecological condition of ecosystem types in the EBSA. Other key features are also listed.


Threat Status

Protection Level

Condition (%)




Ecosystem Types

Agulhas Basin Abyss






Agulhas Plateau Mosaic






Eastern Agulhas Outer Shelf Mosaic






Southwest Indian Lower Slope






Southwest Indian Mid Slope






Southwest Indian Seamount






Southwest Indian Slope Seamount






Southwest Indian Upper Slope






Other Features

  • Fragile species, particularly associated with the seamounts
  • Spawning area for sardine, anchovy, horse mackerel and hake
  • Migratory species, e.g., leatherback turtles.
  • Upwelling



Relevant Pressures and Activities (impact, extent)

  • There are four pressures present in this EBSA, of which shipping is the only one that covers the entire EBSA extent and has the highest cumulative pressure profile.
  • The key pressure in this EBSA that most directly impacts the features for which the EBSA is described is pelagic longlining. Midwater trawling and offshore trawling are also present, but each comprise a fraction of a percent of the extent, thus having a limited impact on the key biodiversity features in the EBSA. These activities will need to be managed particularly well in order to protect the fragile benthic biodiversity, spawning areas and fish assemblages for which this EBSA is recognised. Bycatch mitigation of top predators and migratory species in pelagic longlining will also need careful attention given that this area is highly used by Critically Endangered leatherback turtles, and is recognised as one of the sites in South Africa with the greatest interaction between longlining and leatherbacks, especially in Autumn and Spring.
  • Activities in South Africa that are not present in this EBSA include: abalone harvesting, alien invasive species, beach seining, benthic (hake) longlining, coastal development, coastal disturbance, dredge spoil dumping, gillnetting, kelp harvesting, linefishing (commercial and recreational), mariculture, mean annual runoff reduction, mining (prospecting and mining), naval dumping (ammunition), oil and gas (exploration and production), oyster harvesting, tuna pole fishing, ports and harbours, prawn trawling, recreational shore angling, shark netting, small pelagics fishing, south coast rock lobster harvesting, squid fishing, subsistence harvesting, inshore trawling, wastewater discharge, and west coast rock lobster harvesting; noting that some of these are coastal pressures that do not apply to offshore EBSAs.


Map of cumulative pressure from all activities in the EBSA and surrounds. Darker reds indicate higher pressure intensity.


Pressure (in arbitrary cumulative pressure units, CPUs) summed for each pressure in the EBSA, per proposed EBSA biodiversity zone, ranked left (highest) to right (lowest) by the overall relative importance of pressures in this EBSA. Note that offshore and midwater trawling each comprise <1% of the EBSA pressure profile.



Management Interventions Needed for the EBSA

Improved place-based protection of EBSA features should be pursued. In support of this, the EBSA is divided into a Biodiversity Conservation Zone and an Environmental Impact Management Zone, both comprising several areas within the EBSA. The aim of the Biodiversity Conservation Zone is to secure core areas of key biodiversity features in natural / near-natural ecological condition. Strict place-based biodiversity conservation is thus directed at securing key biodiversity features in a natural or semi-natural state, or as near to this state as possible. Activities or uses that have significant biodiversity impacts are incompatible with the management objective of this zone. If the activity is permitted, it would require alternative Biodiversity Conservation Zones or offsets to be identified. If this is not possible, it is recommended that the activity is Prohibited. Where possible and appropriate, the Biodiversity Conservation Zones should be considered for formal protection e.g., Marine Protected Areas or Other Effective Area-Based Conservation Measures (OECM). The aim of the Environmental Impact Management Zone is to manage negative impacts on key biodiversity features where strict place-based measures are not practical or not essential. In this zone, the focus is management of impacts on key biodiversity features in a mixed-use area, with the objective to keep biodiversity features in at least a functional state. Activities or uses that have significant biodiversity impacts should be strictly controlled and/or regulated. Within this zone, ideally there should be no increase in the intensity of use or the extent of the footprint of activities that have significant biodiversity impacts. Where possible, biodiversity impacts should be reduced.

As far as possible, the Biodiversity Conservation Zone was designed deliberately to avoid conflicts with existing activities. Shackleton Seamount Complex also includes one MPA that is partially within the EBSA: South West Indian Seamounts MPA. The activities permitted within this MPA are not considered as part of the EBSA management recommendations because these are as per the gazetted regulations.


Proposed zonation of the EBSA into Conservation (medium green) and Impact Management (light green) Zones. MPAs are overlaid in orange outlines, with the extent within the EBSA given in dark green. Click on each of the zones to view the proposed management recommendations.


Protection of features in the rest of the Conservation Zone may require additional Marine Protected Area declaration/expansion. Other effective conservation measures should also be applied via Marine Spatial Planning (MSP) to ensure that the existing activities/uses are appropriately controlled to ensure compatibility of activities with the environmental requirements for achieving the management objectives of the EBSA Biodiversity Conservation and Environmental Impact Management Zones.

Based on the compatibility of sea-use activities with the management objective of each EBSA zone (see table below, from the sea-use guidelines of the National Coastal and Marine Spatial Biodiversity Plan), it is recommended for MSP that compatible activities are managed as General activities, which are those that are permitted and regulated by current general rules and legislation. Activities that are conditional are recommended to be managed as Consent activities, which are those that can continue in the zone subject to specific regulations and controls, e.g., to avoid unacceptable impacts on biodiversity features, or to avoid intensification or expansion of impact footprints of uses that are already occurring and where there are no realistic prospects of excluding these activities. Activities that are not compatible are recommended to be Prohibited, where such activities are not allowed or should not be allowed (which may be through industry-specific regulations) because they are incompatible with maintaining the biodiversity objectives of the zone. These recommendations are subject to stakeholder negotiation through the MSP process, recognizing that there will likely need to be significant compromises among sectors. It is emphasized, as noted above, that if activities that are not compatible with the respective EBSA zones are permitted, it would require alternative Biodiversity Conservation Zones or offsets to be identified. If this is not possible, it is recommended that the activity is Prohibited.


List of all sea-use activities, grouped by their Marine Spatial Planning (MSP) zones, and scored according to their compatibility with the management objective of the EBSA’s Biodiversity Conservation Zone (i.e., Critical Biodiversity Area, CBA) and Environmental Impact Management Zone (i.e., Ecological Support Area, ESA). Activity compatibility is given as Y = yes, compatible, C = conditional or N = not compatible, with major activities that are present in the EBSA shaded in grey.



Activity Evaluation Per Zone: Zoning Feasibility

[To be updated]

Proposed zonation of the EBSA, with the cumulative intensity footprint of activities within the EBSA (sorted highest to lowest) given relative to the national footprint of those activities to illustrate feasibility of management interventions.

All activities present in the EBSA comprise <4% of their respective national footprints. Of these, pelagic longlining has the highest proportion of its national footprint in the EBSA, and midwater trawling, the lowest proportion. Both of these activities are recommended to continue as Consent activities in both EBSA zones. Offshore trawling is recommended to continue in the Impact Management Zone where it currently exists, but to be Prohibited from the Conservation Zone where it currently does not exist and where it conflicts with the management objectives of that zone. Shipping is recommended to continue under current general rules and legislation. Thus, in all cases, the EBSA zonation has no or minimal impact on the national footprint for the listed marine activities.


Research Needs

There are no specific research needs for this EBSA in addition to those for all EBSAs. However, the need to collect foundational biodiversity information by sampling the seamounts and understanding their broader ecological role is especially highlighted for this site.


Future Process

Portions of the EBSA have been gazetted for inclusion into the Southwest Indian Seamount MPA. It is unclear if this EBSA will be subject to detailed attention in the MARISMA EBSA status assessment and management options workplan.