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The Dutch multinational Nutreco, the largest fish farming and fish feed company in the world, has long been involved in research looking at the link between eutrophication and fish feed (Talbot and Hole: 1994) but continues to discharge wastes directly into pristine coastal waters. EC-sponsored research has also highlighted the negative effects of waste loadings on fish health (EC: 2000f). And there are public health concerns surrounding shellfish poisoning events such as Amnesic, Diarrhetic and Paralytic Shellfish Posioning (ASP, DSP and PSP) related to salmon farms. For example, DSP affected mussels collected from salmon cages in Loch Seaforth in Scotland (Sandison: 2000) led to 49 people in two London restaurants being treated for “nausea, vomiting, diarrhoea, abdominal pain, and feeling feverish” (Scoging and Bahl: 1998). The technology required for closed containment systems already exists (G3 Consulting: 2000) and is being commercially developed in Canada (Cutland: 2002) but it has not been adopted in Europe as farmers dismiss it as too expensive. The Commission’s latest proposals for “new waste collection systems under cages” represent the bare minimum (EC: 2002c) – indeed, Scottish research has existed for years (SEPA: 1998a). The suggestion that Council Directive 91/676/EEC (which “aims to reduce water pollution caused or induced by nitrates from agricultural sources, including the spreading or discharge of livestock effluents”) “should be extended to include intensive fish farming” is a welcome one but not before time (EC: 2002c). In allowing sea cages to discharge contaminated wastes into the sea, however, countries are permitting farmers the free use of pristine coastal waters as an open sewer (Folke and Kautsky: 1994). Closed containment systems would not only stem the tide of pollution from sea cages but would also prevent escapes, stop the spread of diseases and parasites to wild fish and reduce the need for chemicals.
2) Escapes:
EC-sponsored research has highlighted the negative impacts of farmed salmon escapees on wild fish in Norwegian, Irish, Scottish and Spanish rivers (McGinnity et al: 1997, Clifford et al: 1998, Fleming and Einum: 1997, EC: 2000e, EC: 2000h, Fleming et al: 2000, McGinnity et al: 2002, Scottish Executive: 2002b). AQUAWILD, for example, aims “to assess genetic and environmental impacts of cultured fish on wild conspecifics at various life stages through competition and interbreeding” (EC: 2002h). A forthcoming scientific paper by researchers at the Queens University Belfast will reveal the results of a 10-year Irish investigation (funded by the EC) into the impact of escaped farmed salmon on wild fish (McDowell: 2002). Preliminary results suggest that farmed fish escapes and hatchery-reared fish are having such an impact that wild salmon stocks are precipitating into an “extinction vortex” (McGinnity et al: 2002). As well as spreading parasites and ‘genetic pollution’ via interbreeding and hybridisation, escapees have the capacity to spread infectious diseases to wild fish populations. For example, in Scotland since May 2002 (when it became law to report escapes) 3 out of the 4 escapes (totalling 57,000 fish: equivalent to the entire wild salmon catch in Scotland) came from farms infected with Infectious Pancreatic Necrosis (IPN). New information from the Scottish Executive reveals that there have been 28 escape incidents (involving an estimated 500,000 farmed fish) from Scottish fish farms affected by IPN restrictions since 1998 (Scottish Parliament: 2002b).
The inevitable risk of escapes was something that the UK’s Agriculture, Environment and Biotechnology Commission took into consideration in September 2002 when it recommended a ban on GM salmon in sea cages (AEBC: 2002). Such a precautionary position is reinforced by the EC’s ‘Strategy on the Sustainable Development of European Aquaculture’ which states that: “The potential deliberate release of transgenic fish without containment measures raises public concern in terms of risk to the environment” (EC: 2002c). However, the EC’s ongoing investment into GM fish technologies and research (including salmon, tilapia, trout and carp) does not inspire confidence that GM aquaculture species will not be commercially developed (EC: 2000d, EC: 2000g, Carrell: 2001a, 2001b, 2001c, 2001d, Carrell and Lean: 2001, EC: 2002k, EC: 2002l). Field trials of GM salmon took place in Scotland on the shores of Loch Fyne as far back as 1995-6 (BBC: 2000a). EC-funded GM salmon research has been conducted at the National University of Ireland in Galway (EC: 2000d, EC: 2000g) although the researchers involved have been reluctant to divulge details (Charron: 2001). And outside the EU, Hungary has already completed GM fish experiments with Chinook salmon, carp and zebrafish (EC: 2002j).
In February 2002 over half a million salmon escaped in a single incident in the Faroes (Gardar: 2002a). In Scotland alone there have been over 1 million reported escapes since 1997 (Aitken: 2002) with evidence of interbreeding with wild salmon and hybridisation with brown trout (Webb et al: 1991, 1993, Youngson et al: 1997, 1998). In Norway, such is the historical problem of mass escapes, that some rivers are comprised of up to 90% farm escapees (Saegrov et al: 1997, Fleming and Einum: 1997, Fleming et al: 2000). And in Ireland, some river systems have been found to contain more farmed fish than wild fish (Crozier: 1993, 2000, Clifford et al: 1998). The global problem of salmon escapes is so evident that Norwegian farmed salmon are now resident in the Faroes (Hansen et al: 1999) and salmon that escaped from an Irish farm in August 2001 were caught in English, Scottish and Welsh rivers (Milner and Evans: 2002). Moving cages further offshore will only increase the risk of escapes. Closed containment systems are the only safe solution. Yet given the sheer number of escaped farmed salmon and the negative impact of hatcheries on wild salmon (McGinnity et al: 2002) the very future of wild Atlantic salmon may already be in question. That tuna, sea bass, sea bream, sea trout, cod, halibut, haddock, turbot and sole are already being farmed (and are already escaping) is a disaster waiting to happen.
3) Diseases and parasites:
According to the EC “infectious disease poses the biggest single threat to aquaculture” (EC: 2002f). Infectious Pancreatic Necrosis (IPN) and Infectious Salmon Anaemia (ISA) are the latest in a long line of infectious diseases such as furunculosis to decimate the salmon farming industry. New diseases are appearing all the time. EC-sponsored research is now addressing the emerging problems of salmon pancreas disease (SPD) and sleeping disease (SD) in farmed salmon (EC: 2002d). Another EC-sponsored project, SALIMPACT, is investigating the impact of disease transmitted through the contact between farmed and wild fish (EC: 2002h). GM technology has also been applied to study ways of combating disease and conferring disease resistance (EC: 2002l).
Disease outbreaks have also affected the sea bass and sea bream industries in the Mediterranean. The European Aquaculture Society, for example, has referred to “enormous problems like Pasteurellosis and Nodavirosis” affecting sea bass and sea bream (EAS: 1996). The intensification of culture of sea bass and sea bream “has provoked some severe disease problems” (Agius and Tanti: 1997). The main parasitic infections include Ichtyobodo sp., Ceratomyxa sp., Amyloodinium ocellatum, Trichodina sp., Myxidium leei, and Diplectanum aequans. Cysts of unknown microsporidia found in skeletal muscles of market size sea bream at varying incidences have caused problems with marketing on European Union markets (Agius and Tanti: 1997). Given the current crisis in the sea bass and sea bream industry (Richardson: 2002b) the role of overproduction and the consequent spread of diseases and parasites must not be underestimated.
The spread of diseases and parasites, as in battery chicken farming, is a function of overstocking and intensive production (Paone: 2000b). It is therefore inevitable that new diseases on intensive fish farms will emerge (Meikle: 2002). A report by Compassion in World Farming published in January 2002 calculated that each farmed salmon had the equivalent water space as a single bath-tub of water and called for a halving of stocking densities (Lymberry: 2002). A forthcoming report by the Council of Europe on fish welfare may address the issue of stocking densities on fish farms (EC: 2002c). In the meantime, however, sea cage fish farms will continue to act as reservoirs for infectious diseases and parasitic infestations.
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