Although the Namibian coast is not heavily populated, there are several land uses that negatively impact the rich coastal environment and biodiversity. The main sources of economic development in Namibia, in particular within the four coastal regions are all resource-based including a growing nature-based tourism industry, an overall expanding extractive industry (oil and gas exploration and off-shore mining of minerals) and a commercial fishing industry with growing aquaculture. These activities have cumulative impact on the coastal environment and its steady degradation threatens the economic and health well-being of all Namibians.
The major threats to the environment and biodiversity along the coast are in particular:
Unfortunately, these growing threats are also exacerbated by the lack of integrated conservation and development planning in the Namibian coastal region, coupled with poor management of resources in the face of increased pressures.
In terms of scale, impacts and economic importance, diamond mining is the most prominent industrial activity in Namibia. While diamond mining does not require the use of toxic chemicals vast amounts of sand are moved in order to extract the diamonds. Mines are generally located in isolated areas and they require substantial infrastructural development such as housing, recreational facilities, roads, maintenance facilities, waste disposal, water and power supply etc. Mining of diamonds along Namibia’s coast has been and continues to be an environmentally invasive activity with operations still underway in the ‘Sperrgebiet’ stretches from the Orange River in the south to latitude 26ºS in the north, extending 100 km inland and offshore.
Impacts from mining operations on the coast lead to huge degradation of landscapes, destruction of habitats and pollution of groundwater as sea based operations involve the removal of gravel from intertidal and subtidal habitats, whereas land based mining involves the removal of the sand overburden until bedrock is exposed. In some areas, sections of the tidal zones are reclaimed by building a surrounding dyke (seawall) and then pumping out the seawater. Sediments are then removed in order to locate the buried diamonds.
On a local scale, these activities are highly destructive to biodiversity. The substrate is significantly altered and entire communities may be disturbed or totally eradicated. Offshore mining is now largely developed and have an important negative impact on sea bottom. The disposal of unwanted material results in direct impacts of the plume produced by particulate material. This is followed by subsequent smothering of benthic organisms, most of which are deposit and filter feeders. Consequently, there is a marked change in bottom-dwelling communities in areas where suspension feeders will survive the increased input of particulate material. It cannot be excluded that local populations of rock lobster are also affected by both dredging and disposal of fine sediments.
The Erongo region is experiencing a boom in uranium mining as a result of the phenomenal increase in the price of the commodity. Low-grade deposits have become viable, and the investment regime in Namibia has made the country an attractive investment haven for many mining companies, the vast majority foreign and junior companies. All the uranium mines are being developed in sensitive desert environments and the huge water demand will seriously impact our scarce water resources. There are impacts from the mine itself and also from all the infrastructure related to production of the mine such as access road, power line and water pipeline. These infrastructures have a considerable impact on the desert environment in particular on wildlife (can't cross the water pipeline) and the landscape aestheticis (the beauty of the desert is compromised and tourists may not want to revisit the Namib). A consequence of this uranium boom is development that can compromises the natural environment and undermines the creation of sustainable economies in local communities.
Other kinds of mining are also occurring on our coast such as salt and dimension stone mining. Quarries and sand mining also impact the environment. They are small scale mines but the visual impact is not negligible.
For more information about mining activities in Namibia, consult the following websites:
Marine pollution is generally not an issue in Namibia due to the vastness of uninhabited coastal areas, the relative low intensity of industrial activities concentrated in few urban centres such as Henties Bay, Walvis Bay, Swakopmund and Lüderitz and the absence of coastal agricultural land. In the vicinity of the urban centres water quality is generally poor due to high organic levels, uncontrolled wastewater disposal by the fishing industry, minor oil spills and sewage from ships. In some cases high concentrations of heavy metals were recorded in bottom sediments (O'Toole 1995). Spillages and disposal of inorganic pollutants, primarily hydrocarbons and anti-fouling paint, into the sea are additional threats, while localised shore litter, primarily plastics, originate from anchored vessels and the harbours. To some extent, air pollution is experienced from the fish factories in Walvis Bay, from sewerage works, from solid waste dump sites and from certain operations at the Rössing Uranium Mine.
Due to the coastal morphology, aridity of climate on the coast and the small Namibian population, only a tiny section of the coast is inhabited. However many projects have been (and are planned to be) established close to sensitive areas in particular inappropriate buildings have been built close to the shoreline in central Namibia. The houses, the majority for holiday makers, that have been built along the coast between Swakopmund and Walvis Bay pose threats to the environment as this area supports more resident and migrant birds than any other stretch of beach in the country. It also provides feeding and breeding grounds for the breeding endemic Damara Tern. These developments have already started to suffer the effects of coastal erosion, following higher tides and more frequent swell. Coastal erosion will increase with climate change. There has been an absence of transparency in the developments resulting in them being extremely controversial. Little thought has been given to biodiversity protection and mainly people that are not trained in these fields or come from far away from the coast are busy advising developers who are insensitive to local concerns.
The primary products of the fishing industry in Namibia are canned pilchards, fishmeal, fish body oil, rock lobster and various processed white fish (smoked, dried and frozen). The fishing resources of Namibia were heavily overexploited in the past four decades. Uncontrolled exploitation of pelagic fish resources (especially pilchards) by South African fleets in the 1950s was followed in the mid-1960s by extensive fishing by other foreign fishing fleets, which seriously depleted stocks of hake and mackerel. Variable climatic conditions, poor management also caused a dramatic decline in fish resources in the country. After independence in 1990, a 200 mile exclusive economic zone was declared within which fishing by foreign trawlers is prohibited except under license to Namibian companies.
Walvis Bay and Lüderitz are the only two fishing harbours in the country. Walvis Bay (with a maximum draught of 9 meters) is the only deep-water port in Namibia and is the main fishing harbour; it is also the location of virtually all processing industries and servicing facilities.
In 2005, 552 164 tonnes of fish were harvested in Namibian waters. Of these, 25 128 were pilchard, 158 060 hake, and 327 700 horse mackerel (cf. Table 1: Harvest of the main commercial species, 2001-2005). The final value of processed products (export value) that year was around US$376.0 million.
|Pilchard||10 763||4 160||22 255||28 605||25 128|
|Hake||173 277||154 588||189 305||173 902||158 060|
|Horse Macherel||315 245||259 183||360 447||310 405||327 700|
|Monk||12 390||15 174||13 135||8 961||10 466|
|Kingklip||6 607||7 210||6 603||7 067||5 567|
|Tuna||3 198||2 837||3 371||3 581||3 654|
|Crab||2 343||2 471||2 092||2 400||2 480|
|Other Fish Specieis||30 810||77 407||33 644||31 997||18 934|
|Total Fish Harvest||
|Seals||44 223||40 000||34 000||31 971||64 167|
|Seaweed (Gracilaria Collection)||800||500||288||n/a|
Table 1: Harvest of the main commercial species, 2001-2005 (tonnes) (Sources: MFMR, annual report 2005)
Fishery has an impact on natural marine resources by removing a certain portion of the stock and the physical alteration of habitats. If not balanced and regulated both factors can have disastrous consequences for stocks of commercially exploited species and ultimately for those who derive benefit from their exploitation.
Physical destruction of the benthic habitat occurs through aggressive trawling techniques, particularly beam trawling, as well as the large scale incidental catches of seabirds and marine mammals through the use of drift-nets. Both operations are legislated against in Namibian waters. Bottom trawling for species such as hake and monkfish most certainly has an impact on demersal habitats. Habitat degradation can potentially result in a loss of species richness, as habitats are made unsuitable for certain species.
Fisheries activities can also change the genetic composition of exploited populations through catch selectivity. Usually, larger individuals are targeted and their removal from the breeding community implies, in evolutionary terms, that there is directional selection for smaller size at maturity, smaller final size, decreased growth rate and younger age at maturity.
Aquaculture and mariculture started almost twenty years ago. The oyster production in Walvis Bay and Lüderitz is growing. Impacts from aquaculture and mariculture can include pollution, introductions of alien species and in the bay area east of the Walvis Bay peninsula it was recently observed that the numerous oyster farms have led to the entanglement of a whale calf.
For more information about fisheries in Namibia, consult the following websites:
The Namibian coast is an important tourism destination mainly because of its angling and dune off-road driving opportunities.
Unsustainable tourist and holiday maker behaviour such as uncontrolled (off-road) recreational driving leads to physical degradation and the destruction of unique habitats, especially of highly fragile lichen fields and of breeding areas of endangered species, such as Damara Terns. In the coastal area between Swakopmund and Walvis Bay, including the dunes, off road recreational vehicle activities such as quad bikes, 4x4 and motorbikes have created over the past years a number of conflicts. Off-Road Recreational Vehicle (ORV) driving can cause major impacts on vegetation and fauna and in particular their tracks cause visual impacts to the aesthetic impression of the dunes and the surrounding gravel plains. Breeding activity (larvae, young and eggs of beetles, spiders and reptiles) are impacted especially on the slipfaces of the dune areas where these animals concentrate. Further, aesthetic degradation due to ORV impacts may - besides being a nuisance to parts of the local communities - result in reduced attraction of the area as a recreational destination.
Littering of the beaches and the desert due to increasing tourism is a general albeit not a significant problem.
Recently, Walvis Bay with its boat and catamaran trips attracts more tourists interested in viewing marine and coastal wildlife in the bay and around the peninsula. The pressure on seals, dolphins and recovering whale populations is increasing with the growing number of tour operators. It is necessary to be very careful and vigilant in particular as the Southern Right Whales are slowly recovering from extinction in the Namibian waters.
Walvis Bay used to be a major breeding ground for Southern Right Whales before they became extinct through over harvesting in the early 1800s.
Another problem is, low flying aircraft ignoring height restriction and no-fly zones over Ramsar sites and Important Bird Areas known for massive populations of shorebirds, flamingos and seabirds, e.g. in Walvis Bay, Sandwich Harbour and the coastline between Swakopmund and Walvis Bay.
Trends in offshore oil exploration in Namibia indicate that further licensing will take place and that exploratory drilling activities on the continental shelf will continue into the foreseeable future. It is also likely that commercial development of, and production from, the Kudu gas field is taking place since 2007. In the wake of offshore oil drilling operations, the marine and coastal environment is highly vulnerable, and under certain conditions even exposed to long-lasting degradation. EIAs conducted by Norsk Hydro (1993a), Sasol (1994), Ranger Oil (1994), and Chevron (1995a,b,c) for offshore hydrocarbon exploration in Namibia broadly cover all environmental risks. The EIAs conclude that the main impacts from exploratory drilling activities on the local marine environment would be the discharge of water-based drilling muds, sediment plumes in the water column, accumulation of discharged drilling muds and cuttings on the seabed, accumulation of heavy metals in bottom sediments, and possible toxic effects of mud additives on marine organisms and communities.
The threats to the local biota and marine environment are regarded as insignificant, given the depth of water at drill sites, the short duration of drilling activity (a few weeks), and the small number of wells in relation to the expanse of the continental shelf. Environmental threats arising from blow-outs are also assessed in detail, and response and contingency plans prepared which include drift and dispersal trajectories, containment and recovery as well as cleanup operations.
While the magnitude of the mentioned impacts is regarded as minimal (O'Toole, 1997) major environmental threats would be expected from well "blow outs" during offshore hydrocarbon explorations. Such events, although fairly rare could release over 3000 barrels of crude oil per day into the marine environment. This could have a devastating impact on the living marine resources. Commercially important fish, spawning grounds, marine birds and mammals could be affected, and slicks could affect pristine terrestrial habitats, wetlands and amenities in important tourist areas.
For more information about oil and gas exploration activities in Namibia, consult the following website:http://www.mme.gov.na
The marine environment undergoes constant change through regional and local variations in wind patterns, upwelling intensity and water circulation. These changes directly affect temperatures, nutrient availability and plankton production, which in turn markedly influence fish distribution, spawning and future growth. Levels of dissolved oxygen in the water may also change rapidly as patches of low-oxygen water move. Seasonal changes in atmospheric pressure also control the penetration of warm Angolan Current waters into the northern Benguela region, with southerly movement of Angolan waters most likely in late summer and autumn. In addition, the exceptional southward incursions of warm Angolan waters as far as Walvis Bay, known as Benguela-Niños, occur on a decadal scale. Benguela-Niños, have been recorded in 1934, 1949, 1963, 1973/74, 1984 and 1995. Usually these effects are only temporary, although warm Angolan Current waters may intrude as far south as Walvis Bay, for up to six weeks. Ecological disturbance may result from both the temporary introduction of species of tropical West African origin, and adverse environmental conditions for the locally occurring species. Environmental changes are marked by reductions in plankton production associated with decreased food availability for consumers. Survival of juvenile pelagic fish is also reduced, with potentially disastrous consequences for stocks. The combination of these environmental changes creates a highly variable marine environment. It also makes the environment unpredictable, leading to mortalities of organisms (e.g. rock lobster) that cannot cope with, or escape from, sudden changes. Similarly, fish stocks (e.g. hake) can dramatically decrease or shift to previously unrecorded areas and depth.
During the summer and winter months, sulphur eruptions occur in inshore waters and pose local problems to the marine environment of the Namibian coast especially in the central region, between Cape Cross and Conception Bay. Many visitors' tales of rock lobster and other animals literally walking out of the sea. Fish mortalities often result and the sea takes on a lime green colour. Such eruptions are accompanied by a characteristic pungent smell along the coast. Bottom-dwelling bacteria produce sulphur as a product of decomposition, and they may form patches of concentrated sulphur. Such complex chemical and biological processes are often associated with the occurrence of harmful algal blooms, causing large-scale mortalities to fish and crustaceans. Decay of blooms known as red tides can also lead to localised oxygen deficiency and promote the formation of highly toxic hydrogen sulphide. The effects of global warning through climate change are already seen on the Namibian coast and will be more visible shortly: with the rise of sea level, coastal erosion will be more aggressive; increase of air and water temperature; harsh droughts will occur more often. These will impact seriously our environment and consequently our economy.
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