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State of Marine Biodiversity in South Africa
compiled by J.C. Pauw & B.D Durham.
Marine research in South Africa gets a boost this year with a 17% increase in
allocation of funding from the Department of Environmental Affairs and Tourism (DEAT).
This is welcome news for marine research community. A report that evaluates
current knowledge, identifies data gaps and highlights future priority actions
and research requirements is outlined below.
The sea is a commonage that provides humans with food, recreation, a mode of transport and opportunities for mineral extraction. Overall, the wholesale value in 1995 for all commercial fishing sectors in South Africa alone totalled R1.7 billion. Small-scale fisheries, and their associated industries, such as the linefishery, contribute significantly to the economic welfare of many towns and cities along the South African coastline.
Unfortunately, because most of the sea's assets are hidden from human observation, care for the environment lags far behind that of the terrestrial environment. For example the indiscriminate dumping of substances is tolerated at sea to an extent that is generally not permitted on land, and most exploitable living resources are fully-utilised or over-exploited.
The degradation of the marine and coastal environments affects the health and functioning of the ecosystems, which reduces the reproductive success of individual species. Tied to this, the current over-exploitation of many resources reduces the optimal yield, thereby reducing the financial returns of the broader fishing industry, which contributes to poverty and job losses.
The South African marine and coastal life-supporting systems are showing clear symptoms of over-exploitation and degradation, and pressures that bear on resources are likely to increase for the foreseeable future. At present the major threats to marine biological diversity are:
- Excessive and increasing exploitation of keystone species by sophisticated industrial, illegal, recreational and subsistence users, resulting in radical and perhaps irreversible changes in community structure (e.g. reducing parent stock to the point where recruitment fails).
- Expertise in ecosystems approaches to fisheries management is very limited and this has led to large piscivorous fish species having declined relative to smaller species over the course of the twentieth century as well as possible changes to gene pools.
- There is a dearth of mathematically competent fisheries biologists or biologically competent mathematicians.
- Between 10% and 64% of a stock is annually removed by fishing gear selecting against certain traits, such as large size and fast growth, aggression and schooling behaviour annually. Such intense selection can change physical, physiological and behavioural attributes of wild stocks in a few generations, and impact on their fitness, production and
catchability.
- Abalone and kob species are severely overfished and fish stock is generally overfished or
fully-utilised.
- Patagonian toothfish is heavily poached by international fleets off the Marion and Prince Edward Islands
- Bycatch rates, leading to incidental mortality on non-target species, vary between five and 70%. A serious bycatch issue is currently the mortality of sea birds affected by long-line operation.
- Marine organisms are poached to varying degrees by all fishing sectors. This is because provincial enforcement agencies that are charged with MPA management lack sufficient capacity to enforce the protection of offshore resources, partly because of their terrestrial bias, and also because there are no management plans in place for the
MPAs.
- Estuaries and dune systems are being damaged by development and degraded by trampling and off-road vehicles.
- The protection of estuaries is regarded as inadequate because most of the protected estuaries are small, insignificant systems, the protection within an estuary is limited, or for the protection of birds only.
- There is confused legislation and limited capacity regarding the management and use of estuaries.
- Beaches and ocean waters are polluted. Pollution comes in the form of plastic, oil, sewerage and sedimentation and causes toxicity, eutrophication, sediment loading and a loss of aesthetic appeal. The latter particularly impacts on tourism opportunities.
- The major sandy-beach ecosystems of the Eastern Cape are not protected
- Changing temperature regimes in the marine environment due to climate change will raise the sea-level and could severely alter species distribution patterns, reproductive success and production rates as well as affecting islands, estuaries and coastal systems.
- There are large areas of South Africa's marine environment where the biological communities are poorly described at the species level due to a serious shortage of taxonomists
- The European mussel Mytilus invaded the West Coast, where it has restructured intertidal communities.
- The marine bioprospecting industry is poorly regulated in South Africa
However, South Africa could use certain opportunities and strengths to conserve its marine biodiversity:
- Develop fishing of under-utilised resources including various trawl bycatch species, deepwater fish species such as orange roughy, oreo dories, seals, whelks, common bait and certain seaweeds.
- South Africa's marine invertebrate, algal and bacterial resources are a globally recognised, potential source of commercially exploitable chemical entities.
- Tourism and other forms of non-consumptive use offer major opportunities for development.
- Mariculture can be developed into a major industry.
- South Africa has thirteen marine protected areas, eleven general restricted areas, nineteen fishery sanctuaries, twenty-three estuarine protected areas and four National Parks in the marine environment - and many additional coastal reserves. However, inadequate coverage is given to coastal dunes and estuaries.
- The draft White Paper for Sustainable Coastal Development has been developed through an extensive public participation process. The policy is intended to maximise opportunities for economic and social development connected with coastal resources through the maintenance of the health, diversity and productivity of coastal ecosystems.
- The Marine Living Resources Act and the White Paper on a Marine Fisheries Policy recognise the need to protect ecosystems and species, and the former empowers the Minister to regulate activities that may threaten marine biodiversity.
- There is an immediate opportunity, following from the publication of this Status Report on Marine Biodiversity for biological, social and economic sciences to collaborate, perhaps on a regional basis, to establish long-term research and management plans for the sustainable use of marine and coastal resources.
This article by news@NRF.
This publication was produced by the NRF, in conjunction with the South African Network for Coastal and Oceanic Research (SANCOR) and Marine and Coastal Management. The report is available in electronic format
at: www.nrf.ac.za/publications/marinereport
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