Introduction
It is important to introduce my background so that the reader can fully understand my position and where I come from. My lineage derives from the 'Namgis and Kwagu’ł First Nations of the Kwakwaka’wakw (Kwak’wala speaking peoples). The Kwakwaka’wakw are located on the North East of Vancouver Island as well as part of the adjacent mainland. The traditional Kwakwaka’wakw diet includes salmon, herring, eulachon, halibut, berries and to a lesser extent, goats, seals, and porpoises. The contemporary diet has recently integrated western foods to complement the collapsed fisheries that was heavily relied on and effectively stewarded for thousands of years (Heaslip, 2008).
The Kwakwaka’wakw, described as the Salmon People, have witnessed profound differences since the fish farms started appearing in their territories (Cranmer, 1998). Some of these changes include blackened clam beds, increased sea lice infestation and sea vegetation changes (Richard et al, 2005). The 'Namgis First Nation has always maintained a zero-tolerance policy towards fish farms ('Namgis First Nation). Community interviews reveal that risks to the environment, the local economy, and health and well-being as primary reasons for this opposition (Richard et al, 2005). Richard also links salmon farms to the fact that the 'Namgis have experienced decreased access to and control of resources within their territories (2005).
The Broughton Archipelago, an area this paper focuses on and which currently holds 28 open-net cage sites (BC is approving more licenses), is situated within 'Namgis territories (PFRCC, 2002; Statistic Canada, 2004). According to 'Namgis members, there are effects from the farms that are not yet being researched or its impacts fully understood and action must be taken before its too late (Heaslip, 2008). One of the concerns regarding these farm sites, sea lice and its impact on wild salmon stocks, will be explored in greater detail. It is the position of the 'Namgis First Nation that sea farms are a significant cause for among many things, increased numbers of sea lice ('Namgis First Nation).
The salmon aquaculture industry and several scientists have critiqued the available peer-reviewed evidence linking fish farms to the decline in wild stocks, which if correct could lead to the decimation or extinction of pink salmon populations. The industry objects to further regulation or any drastic actions without more in-depth studies. Although it is agreed that further research is needed to further understand this complex issue, action should be taken immediately to reduce the risks and protect wild salmon stocks.
Increasing numbers of people have come to understand that salmon farming in its current form is unsustainable and a great danger to surrounding ecosystems. It is the intent of this paper to convince the reader that despite disagreements about the extent of the impact sea lice are causing, the negative effects of sea farming practices alone are reason enough to demand change. This debate will be examined from a 'Namgis perspective and recommendations will be put forth for action within the next six months.
Sea Lice
Sea lice are crustacean parasites that commonly live and feed on salmon and other fish species. Of the thirteen species of sea lice only three, Lepeophtheirus salmonis, Lepeophtheirus cuneifer and Caligus clemensi, have been known to attach themselves to farmed and wild salmon in BC waters (Watershed Watch Salmon Society, 2004). The sea louse eats the mucous, blood and skin of salmon and naturally appears within tolerable levels on salmon in the wild (Watershed, 2004). If infestation is high enough, salmon will die. These load limits are still under intense investigation, which is further complicated by the different responses of each salmon species. Female sea lice can lay between less than a hundred to hundreds of eggs at one time with up to six laying cycles per lifetime (Bjorn & Finstad,1999). This means that given the right conditions and an ample supply of hosts, that sea lice can multiply quite readily. Depending on location within the Broughton Archipelago, juvenile salmon sometimes have to navigate through as many as four salmon farms to get to the open ocean (Morton, 2004). This can dramatically increase the chances of infestation at a time when protective scales have not fully developed.
When salmon return to fresh water to spawn, the attached sea lice die after several weeks (Watershed, 2004); therefore, it is logical to assume that salmon farms are a main cause for sea lice infection around farms, which provide many host opportunities because of their year-round activities (Costello, 2006). Sea farm operators use a drug called Slice (emamectin benzoate), which effectively kills most lice present (Stone et al. 2000). It is not a silver bullet however and studies have shown that other crustaceans are impacted by the drug (Waddy et al, 2002; SEPA, 1999). The drug also has low solubility in water and is very likely to accumulate in marine sediments (Brooks, Mahnken & Nash, 2002).
Dwindling Wild Salmon Numbers
The article entitled Epizootics of Wild Fish Induced by Fish Farms states that there is a chance of between 9-95% mortality rate in several pink and chum populations in the Broughton Archipelago (Krkosek, Lewis, Morton et al, 2006). Under normal conditions juvenile salmon would not be infested because sea lice cannot live in water with low salinity for more than three weeks and the previous group of sea lice would have died off (Gillibrand & Willis, 2007). Juvenile salmon enter the sea in the spring without lice several months before the return of wild adult salmon, which commonly return infested within tolerable levels (Morton, 2004). The farms act as incubators for lice that remain in the areas surrounding spawning grounds. (Krkosek, Lewis Morton et al, 2006). Even a few remaining lice can produce large numbers of infectious larvae and eggs during the spring (Orr, 2007) and salmon farms provide an ideal overwintering habitat not naturally available (Morton et al, 2004). Significantly, Morton rejects the hypothesis that the sea louse L. Salmonis naturally occurs at higher levels in the Broughton Archipelago (Morton et al, 2004) and research suggests that infestations of sea lice regularly occur in juvenile wild salmonoids near farms, dramatically increasing the chances of infestation and death (Morton et al. 2004, 2005; Krkosek et al. 2005).
Furthermore, Morton was able to provide a link between the infestation levels and mortality of juvenile salmon, while providing a correlation between fallowed farm sites and a decline in copepodids (parasitic stage of louse) within 1km, which has prompted further studies (Morton & Routledge, 2005). Ultimately, Krkosek and Morton utilized the Department of Fisheries and Ocean’s (DFO) escapement data that suggests farms can cause infestations of sea lice that decrease capacity of coastal habitats to support wild salmon numbers and warns that it could lead to 99% pink salmon collapse within four generations (Krkosek & Morton, 2007)! This figure has come under intense scrutiny.
Industry-led Opposition
The BC salmon farming industry employs approximately 2800 people, is the largest agricultural exporter in BC, the fourth largest producer worldwide and contributes $800 million to the provincial economy (BC Salmon Farmers Association). It is important to note that initially the fish farm supporters did not counter the peer-reviewed scientific process with studies and evidence of their own. This evidence does not refute the linkage between sea lice and salmon farms, rather it works to uncover other possible reasons that contribute to the decline of salmon stocks near salmon farms, while working to challenge the scientific methods of published studies.
Brooks has challenged the growing anti-farm group by examining historical returns to the Broughton Archipelago and pointing out where evidence does not take all factors into consideration. His article states that following years of abundant populations typically fall to lower levels for several years (Brooks & Jones, 2008). A primary factor that was not included in Krkosek’s 2007 article was the use of emamectin benzoate (Slice) on farm populations (Brooks & Jones, 2008). Another factor is the evidence of pink salmon resistance against sea lice that has shown an effective defense that accelerates the rejection of lice from their skin once their weight reaches 0.7g, calling for further research on juveniles weighing less (Jones et al., 2007). Brooks argues that the DFO database actually shows a positive trend since 2003 and that returns are within historical variability (Brooks & Jones, 2008). Both Brooks and Harvey call for more research (Brooks & Jones, 2008; Harvey, 2008a), but Harvey later clarifies his position by stating it is not just a matter of whether or not the science is clear yet, but whether there is enough evidence to prompt action (Harvey, 2008b).
There are several factors that have been identified as possible contributors to wild salmon declines. Beamish speculates that the salinity of the ocean can impact the survival rates of sea lice because they cannot live in salinity levels below 30% (Beamish, Jones et al, 2006a; Morton, Routledge & Williams, 2005). Beamish et al call for better measurements of salinity levels in the Broughton Archipelago (2006). Jones has brought attention to the fact that there are several sources transmitting sea lice besides farmed salmon. It becomes apparent that both farmed and wild salmon may become infected by sea lice from a variety of sources such as over-wintering Coho and Chinook salmon and wild sticklebacks, but this possible transmission needs further study (Jones et al, 2006b).
Brooks challenges Krkosek and Morton’s work as they go back and forth in their debate, each side minimizing the other’s assumptions. In 2005, Brooks responded to Krkosek’s rebuttal by stating that his literature does not take into consideration the life cycle of sea lice and the ideal/adverse living conditions present during his studies. In 2008 Brooks further states that pink salmon are highly variable in the area and that Krkosek should not have excluded major pink salmon producing systems in his analysis. Brooks also questions the mathematical model Krkosek used.
Even though the research debate is still ongoing, the pro-farm group has not disproven that sea lice is reducing numbers, just that the evidence does not necessarily point to substantial losses and therefore drastic action may not be necessary. This is not in line with the precautionary principle (Lauck, Clark, Mangel & Munro,1998). If Krkosek and Morton are correct, it may be too late to effective counter this threat of extinction or drastically reduced numbers. It is clear that the adaptive management being employed by the BC Government is not effectively managing farmed nor by extension wild fishery numbers (BC Government). The provincial and especially federal governments’ tacit support of fish farms by failing to act according to precautionary principles means that for the time being, change will not be demanded from lawmakers. With this in mind, it is important to minimize the risks to the environment.
Among all of this scientific study, which is meant to divorce emotion from the debate and look exclusively at the evidence uncovered, the 'Namgis ‘non-scientific’ observations become ever more important. They are the people who are directly impacted by these events and ongoing debates. The 'Namgis have long held disdain for the atrocious management of fisheries within their territories and the apparent abandonment of the Broughton Archipelago. This has prompted the 'Namgis to fill the research and management gaps left by the DFO, while simultaneously fighting for guaranteed fisheries access and decision-making powers over their territories ('Namgis First Nation). The 'Namgis have considered the concerns of members employed by local salmon farms and believe that they will be just as useful working on closed containment farms. Although a majority disagrees with the industry’s current operations, split opinions start to occur in some communities where employment levels (economic need) start to outweigh the negative impacts of sea farms (Gerwing & McDaniels, 2006).
Recommendations
There are scientists that wish to debate the potential causes that may be attributable to other factors. It is also understood that the entire salmon fishing industry and its supporters have much invested in the form of employment, public relations, government remittances in the form of taxes and the brand of farmed salmon itself (BC Salmon Farmers Association). It is clear that this is a sometimes emotional issue that has polarized communities. In considering recommendations, the first question needed to be asked is: are farmed salmon capable of being sustainable in its current form? The short answer is no. There are many actions that must be taken to alleviate environmental stresses and to turn the industry into a sustainable, profitable business. It is important to understand that salmon itself is not sustainable. As a carnivorous species, salmon consume 3-3.5kg of fish meal for every 1kg of salmon that reaches market (Naylor, 2000). To give an example of the resources needed, the European salmon farming industry needs an area for feed estimated at 40,000 to 50,000 times the surface area of farms, which is equal to about 90% of the primary production of the fishing area of the North Sea (Naylor, 2000).
We must look at lower trophic level fish species that are herbivorous and require fewer resources to grow such as carp, tilapia and catfish. Countries should encourage production of fish other than shrimp and salmon that are fed diets containing little or no fishmeal (Skretting, 2008) and since there currently is a huge market for salmon that is not abating, several things must be done to minimize the current impacts. Scientists need to research alternative ways to reduce the fish meal, fish oil and heavy usage of energy inputs that are needed, possibly toward natural and safe plant proteins (Skretting, 2008), while simultaneously establishing fines that reduce escapes and increasing regulation of environmental safety measures like feed and drug usage as well as the recirculation of waste water (Naylor et al, 2000). Studies demonstrate a correlation between fallowing farm sites and a decline in numbers of copepodids on wild pink/chum juveniles within 1 km of farms and although further studies need to be done, fallowing farms along migratory routes should be a mandatory measure until proven otherwise (Morton & Routledge, 2005).
Sea lice have a negative impact on wild salmon and must be addressed immediately. Salmon are a keystone species and the reduction of wild salmon has wide implications to the surrounding ecosystems (Willson & Halupka, 1995). Until sustainable alternatives have been implemented, Slice treatments must happen weeks before March 1 to reduce sea louse numbers (Orr, 2007). It is important to move regulation away from industry self-policing and have government staff conduct increased and continual random checks without any notice to salmon farm operators. It is hoped this will maintain the highest of standards until more efficient means are implemented.
The 'Namgis want the farms to be land-based, close contaminant tanks ('Namgis First Nation; The Province, February 24, 2008), which could be publically funded to help with the transition. This has support among environmentalists and the Special Committee on Sustainable Aquaculture (British Columbia, 2007), but is thought of as too costly by the BC Salmon Farmers Association and industry. During this transition, biological barriers should be implemented that separates farmed salmon from the surrounding ocean, while a moratorium on any new farm licenses should be put into place. Designs should be energy efficient and process all wastes. The benefits of closed containment include an ‘eco-salmon’ marketing opportunity, substantial food savings, and control of growing conditions such as temperature, disease and water chemistry (Georgia Strait Alliance & David Suzuki Foundation, 2008). Major hurdles to overcome are the substantial start-up costs, cleaning (in a tank system), as well as ongoing energy costs and impacts (Canadian Geographic). Despite these concerns, there have been many examples of viable closed containment fish farming and with appropriate government support, the salmon farm industry will be able to transition to a more environmentally sustainable operation.
References
'Namgis First Nation. Marine Resources. Retrieved November 27, 2008, from http://www.namgis.bc.ca/resource/Pages/Fisheries.aspx
BC Salmon Farmers Association. Retrieved November 28, 2008, from http://www.salmonfarmers.org/
British Columbia. Adaptive Management. Retrieved November 28, 2008, from http://www.for.gov.bc.ca/hfp/amhome/Admin/index.htm
British Columbia. (2007) Legislative Assembly. Special Committee on Sustainable Aquaculture. Special Committee on Sustainable Aquaculture final report, Third Session, Thirty-Eighth Parliament Legislative.
Beamish, R., Jones, S., Neville, C., Sweeting, R., Karreman, G., Saksida, S. &
Gordon, E. (2006a). Exceptional production of pink salmon in 2003/2004 indicates that farmed salmon and wild Pacific salmon can coexist successfully in a marine ecosystem on the pacific coast of Canada. ICES J. Mar. Sci., 63, 1326–1337.
Bjorn, P. & Finstad, B. (1999). The development of salmon lice (Lepeophtheirus salmonis) on artificially infected post-smolts of sea trout (Salmo trutta). Canadian Journal of Zoology, 76, 970-977.
Brooks, K., Mahnken, C. & Nash, C. (2002). Environmental Effects Associated with Marine Netpen Waste with Emphasis on Salmon Farming in the Pacific Northwest, in Responsible Marine Aquaculture. CAB International.
Brooks, K. (2005). The effects of water temperature, salinity and currents on the survival and distribution of the infective copepodid stage of sea lice (Lepeophtheirus salmonis) originating on Atlantic salmon farms in the Broughton Archipelago of British Columbia. Reviews in Fisheries Science 13, 177-204.
Brooks, K. & Jones, S. (2008). Perspectives on Pink Salmon and Sea Lice: Scientific Evidence Fails to Support the Extinction Hypothesis. Reviews in Fisheries Science, 16(4), 403–412.
Gray, M. Raising a Fish Out of Water: A look at Canada's only land-based salmon farm that's taking small fry to full-sized. Canadian Geographic. Retrieved November 28, 2008 from http://www.canadiangeographic.ca/
Costello, M. (2006). Ecology of sea lice parasitic on farmed and wild fish. Trends Parasitol, 22, 475–483. DOI:10.1016/j.pt.2006.08.006).
Cranmer, G. (1998). The Salmon People of Alert Bay Proceedings of the 12th International Abashiri Symposium, Abashiri, Japan.
Foreman, M., Stucchi, D., Zhang, Y. & Baptista, A. (2006). Estuarine and Tidal Currents in the Broughton Archipelago. Atmosphere-Ocean, 44 (1), 47–63.
Gerwing, K., & McDaniels, T. (2006, March). Listening to the Salmon People: Coastal First Nations' Objectives Regarding Salmon Aquaculture in British Columbia. Society & Natural Resources, 19(3), 259-273. Retrieved November 27, 2008. DOI:10.1080/08941920500460864.
Harvey, B. (2008a, February). Science and Sea Lice: What do we Know? B.C. Pacific Salmon Forum.
Harvey, B. (2008b, October 20). On science, sea lice and sitting on the fence: Biologist believes there's more to issue of salmon farming than easy generalities. Times Colonist. Retrieved November 28, 2008, from http://www.canada.com/victoriatimescolonist/index.html
Heaslip, R. (2008). Monitoring salmon aquaculture waste: The contribution of First Nations' rights, knowledge, and practices in British Columbia, Canada. Marine Policy, 32(6), 988-996. ISSN 0308-597X, DOI: 10.1016/j.marpol.2008.02.002.
Georgia Strait Alliance & the David Suzuki Foundation on behalf of CAAR (2008, May). Global Assessment of Closed System Aquaculture. Ecoplan International Inc. Retrieved November 28, 2008 from http://www.farmedanddangerous.org/
Gillibrand, P. & Willis, K. (2007). Dispersal of sea louse larvae from salmon farms: modeling the influence of environmental conditions and larval behavior. Aquatic Biology, 1,63-75.
Jones, S, Prosperi-Porta, G., Kim, E., Callow, P. & Hargreaves, N. (2006b). The occurrence of Lepeophtheirus salmonis and C. clemensi (copepoda: caligidae) on three-spine stickleback Gasterosteus aculeatus in coastal British Columbia. J. Parasitol, 92, 473–480.
Jones, S., Fast, M., Johnson, S. & Groman, D. (2007). Differential rejection of Lepeophtheirus salmonis by pink and chum salmon: Disease consequences and expression of proinflammatory genes. Diseases of Aquatic Organisms, 75, 229–238.
Krkošek, M., Lewis, M., Morton, A., Frazer, L. & Volpe, J. (2006). Epizootics of wild fish induced by farm fish. Proceedings of the National Academy of Sciences of the United States of America, 103, 15506-15510. DOI:10.1073/pnas.0603525103.
Krkošek, M., Ford, J., Morton, A., Lele, S., Myers, R. & Lewis, M. (2007, December). Declining Wild Salmon Populations in Relation to Parasites from Farm Salmon. Science, 318(5857), 1772. DOI: 10.1126/science.1148744.
Lauck, T., Clark, C., Mangel, M. & Munro, G. (1998, Feb). Implementing the Precautionary Principle in Fisheries Management Through Marine Reserves. Ecological Applications, 8(1), S72-S78.
Morton, A., Routledge, R., Peet, C., & Ladwig, A. (2004). Sea lice (Lepeophtheirus salmonis) infection rates on juvenile pink (Oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon in the nearshore marine environment of British Columbia, Canada. Canadian Journal of Fisheries and Aquatic Sciences, 61(2), 147-157. Retrieved November 29, 2008, from CBCA Reference database.
Morton, A., Routledge, R. & Williams, R. (2005, August). Temporal Patterns of Sea Louse Infestation on Wild Pacific Salmon in Relation to the Fallowing of Atlantic Salmon Farms. North American Journal of Fisheries Management, 25(3), 811-821.
Naylor, R., Goldburg, R., Primavera, J., Kautsky, L., Beveridge, M., Clay, J., Folke, C., Lubchenco, J., Mooney, H. & Troell, M. (2000, June). Effect of Aquaculture on World Supplies. Nature, 405, 1017-1024.
Orr, C. (2007). Estimated Sea Louse Egg Production from Marine Harvest Canada Farmed Atlantic Salmon in the Broughton Archipelago, British Columbia, 2003–2004. North American Journal of Fisheries Management, 27, 187–197. DOI: 10.1577/M06-043.1.
Pacific Fisheries Resource Conservation Council (PFRCC). (2002, November). 2002 Advisory: the Protection of Broughton Archipelago Pink Salmon Stocks. PFRCC, Vancouver. Retrieved November 27, 2008 from www.fish.bc.ca/
Richmond, C., Elliott, S., Matthews, R. & Elliott, B. (2005, December). The Political Ecology of Health: Perceptions of Environment, Economy, Health and Well-Being Among `Namgis First Nation, Health & Place, 11(4), 349-365. ISSN 1353-8292, DOI: 10.1016/j.healthplace.2004.04.003.
SEPA. (1999). Emamectin benzoate - an environmental risk assessment. Scottish Environmental Protection Agency Fish Farm Advisory Group.
Skretting. (2008, September 28). Skretting Fed Salmon Yield More Fish Protein Than They Consume. Retrieved November 28, 2008, from http://www.skretting.com/
Statistic Canada. (2004). Aquaculture, Production and Value, Annual: Detailed Information for 2003. Statistic Canada, Ottawa.
Stone, J., Sutherland, I., Sommerville, C., Richards, R., & Endris, R. (2000, May). The Duration of Efficacy Following Oral Treatment with Emamectin Benzoate Against Infestations of Sea Lice, Lepeophtheirus salmonis (Krøyer), in Atlantic salmon Salmo salar L. Journal of Fish Diseases, 23(3), 185-192. Retrieved November 29, 2008. DOI:10.1046/j.1365-2761.2000.00233.x.
The Province. (2008, February 24). A sea-friendly way to farm fish: salmon in Closed Containers Won’t Interfere with Natural Stocks. The Province. Retrieved November 27, 2008 from http://www.theprovince.com/
Waddy, S., Burridge, L., Hamilton, M., Mercer, S., Aikon, D. &Haya, K. (2002). Emamectin benzoate induces molting in American lobster, Homarus americanus. Canadian Journal of Fisheries and Aquatic Sciences, 59, 1096-1099.
Watershed Watch Salmon Society. (2004). Sea Lice and Salmon: Elevating the Dialogue. Watershed Watch Salmon Society. Retrieved November 25, 2008 from http://www.watershed-watch.org
Willson, M. & Halupka, K. (1995, June). Anadromous Fish as Keystone Species in Vertebrate Communities. Conservation Biology, 9(3), 489-497.
It is important to introduce my background so that the reader can fully understand my position and where I come from. My lineage derives from the 'Namgis and Kwagu’ł First Nations of the Kwakwaka’wakw (Kwak’wala speaking peoples). The Kwakwaka’wakw are located on the North East of Vancouver Island as well as part of the adjacent mainland. The traditional Kwakwaka’wakw diet includes salmon, herring, eulachon, halibut, berries and to a lesser extent, goats, seals, and porpoises. The contemporary diet has recently integrated western foods to complement the collapsed fisheries that was heavily relied on and effectively stewarded for thousands of years (Heaslip, 2008).
The Kwakwaka’wakw, described as the Salmon People, have witnessed profound differences since the fish farms started appearing in their territories (Cranmer, 1998). Some of these changes include blackened clam beds, increased sea lice infestation and sea vegetation changes (Richard et al, 2005). The 'Namgis First Nation has always maintained a zero-tolerance policy towards fish farms ('Namgis First Nation). Community interviews reveal that risks to the environment, the local economy, and health and well-being as primary reasons for this opposition (Richard et al, 2005). Richard also links salmon farms to the fact that the 'Namgis have experienced decreased access to and control of resources within their territories (2005).
The Broughton Archipelago, an area this paper focuses on and which currently holds 28 open-net cage sites (BC is approving more licenses), is situated within 'Namgis territories (PFRCC, 2002; Statistic Canada, 2004). According to 'Namgis members, there are effects from the farms that are not yet being researched or its impacts fully understood and action must be taken before its too late (Heaslip, 2008). One of the concerns regarding these farm sites, sea lice and its impact on wild salmon stocks, will be explored in greater detail. It is the position of the 'Namgis First Nation that sea farms are a significant cause for among many things, increased numbers of sea lice ('Namgis First Nation).
The salmon aquaculture industry and several scientists have critiqued the available peer-reviewed evidence linking fish farms to the decline in wild stocks, which if correct could lead to the decimation or extinction of pink salmon populations. The industry objects to further regulation or any drastic actions without more in-depth studies. Although it is agreed that further research is needed to further understand this complex issue, action should be taken immediately to reduce the risks and protect wild salmon stocks.
Increasing numbers of people have come to understand that salmon farming in its current form is unsustainable and a great danger to surrounding ecosystems. It is the intent of this paper to convince the reader that despite disagreements about the extent of the impact sea lice are causing, the negative effects of sea farming practices alone are reason enough to demand change. This debate will be examined from a 'Namgis perspective and recommendations will be put forth for action within the next six months.
Sea Lice
Sea lice are crustacean parasites that commonly live and feed on salmon and other fish species. Of the thirteen species of sea lice only three, Lepeophtheirus salmonis, Lepeophtheirus cuneifer and Caligus clemensi, have been known to attach themselves to farmed and wild salmon in BC waters (Watershed Watch Salmon Society, 2004). The sea louse eats the mucous, blood and skin of salmon and naturally appears within tolerable levels on salmon in the wild (Watershed, 2004). If infestation is high enough, salmon will die. These load limits are still under intense investigation, which is further complicated by the different responses of each salmon species. Female sea lice can lay between less than a hundred to hundreds of eggs at one time with up to six laying cycles per lifetime (Bjorn & Finstad,1999). This means that given the right conditions and an ample supply of hosts, that sea lice can multiply quite readily. Depending on location within the Broughton Archipelago, juvenile salmon sometimes have to navigate through as many as four salmon farms to get to the open ocean (Morton, 2004). This can dramatically increase the chances of infestation at a time when protective scales have not fully developed.
When salmon return to fresh water to spawn, the attached sea lice die after several weeks (Watershed, 2004); therefore, it is logical to assume that salmon farms are a main cause for sea lice infection around farms, which provide many host opportunities because of their year-round activities (Costello, 2006). Sea farm operators use a drug called Slice (emamectin benzoate), which effectively kills most lice present (Stone et al. 2000). It is not a silver bullet however and studies have shown that other crustaceans are impacted by the drug (Waddy et al, 2002; SEPA, 1999). The drug also has low solubility in water and is very likely to accumulate in marine sediments (Brooks, Mahnken & Nash, 2002).
Dwindling Wild Salmon Numbers
The article entitled Epizootics of Wild Fish Induced by Fish Farms states that there is a chance of between 9-95% mortality rate in several pink and chum populations in the Broughton Archipelago (Krkosek, Lewis, Morton et al, 2006). Under normal conditions juvenile salmon would not be infested because sea lice cannot live in water with low salinity for more than three weeks and the previous group of sea lice would have died off (Gillibrand & Willis, 2007). Juvenile salmon enter the sea in the spring without lice several months before the return of wild adult salmon, which commonly return infested within tolerable levels (Morton, 2004). The farms act as incubators for lice that remain in the areas surrounding spawning grounds. (Krkosek, Lewis Morton et al, 2006). Even a few remaining lice can produce large numbers of infectious larvae and eggs during the spring (Orr, 2007) and salmon farms provide an ideal overwintering habitat not naturally available (Morton et al, 2004). Significantly, Morton rejects the hypothesis that the sea louse L. Salmonis naturally occurs at higher levels in the Broughton Archipelago (Morton et al, 2004) and research suggests that infestations of sea lice regularly occur in juvenile wild salmonoids near farms, dramatically increasing the chances of infestation and death (Morton et al. 2004, 2005; Krkosek et al. 2005).
Furthermore, Morton was able to provide a link between the infestation levels and mortality of juvenile salmon, while providing a correlation between fallowed farm sites and a decline in copepodids (parasitic stage of louse) within 1km, which has prompted further studies (Morton & Routledge, 2005). Ultimately, Krkosek and Morton utilized the Department of Fisheries and Ocean’s (DFO) escapement data that suggests farms can cause infestations of sea lice that decrease capacity of coastal habitats to support wild salmon numbers and warns that it could lead to 99% pink salmon collapse within four generations (Krkosek & Morton, 2007)! This figure has come under intense scrutiny.
Industry-led Opposition
The BC salmon farming industry employs approximately 2800 people, is the largest agricultural exporter in BC, the fourth largest producer worldwide and contributes $800 million to the provincial economy (BC Salmon Farmers Association). It is important to note that initially the fish farm supporters did not counter the peer-reviewed scientific process with studies and evidence of their own. This evidence does not refute the linkage between sea lice and salmon farms, rather it works to uncover other possible reasons that contribute to the decline of salmon stocks near salmon farms, while working to challenge the scientific methods of published studies.
Brooks has challenged the growing anti-farm group by examining historical returns to the Broughton Archipelago and pointing out where evidence does not take all factors into consideration. His article states that following years of abundant populations typically fall to lower levels for several years (Brooks & Jones, 2008). A primary factor that was not included in Krkosek’s 2007 article was the use of emamectin benzoate (Slice) on farm populations (Brooks & Jones, 2008). Another factor is the evidence of pink salmon resistance against sea lice that has shown an effective defense that accelerates the rejection of lice from their skin once their weight reaches 0.7g, calling for further research on juveniles weighing less (Jones et al., 2007). Brooks argues that the DFO database actually shows a positive trend since 2003 and that returns are within historical variability (Brooks & Jones, 2008). Both Brooks and Harvey call for more research (Brooks & Jones, 2008; Harvey, 2008a), but Harvey later clarifies his position by stating it is not just a matter of whether or not the science is clear yet, but whether there is enough evidence to prompt action (Harvey, 2008b).
There are several factors that have been identified as possible contributors to wild salmon declines. Beamish speculates that the salinity of the ocean can impact the survival rates of sea lice because they cannot live in salinity levels below 30% (Beamish, Jones et al, 2006a; Morton, Routledge & Williams, 2005). Beamish et al call for better measurements of salinity levels in the Broughton Archipelago (2006). Jones has brought attention to the fact that there are several sources transmitting sea lice besides farmed salmon. It becomes apparent that both farmed and wild salmon may become infected by sea lice from a variety of sources such as over-wintering Coho and Chinook salmon and wild sticklebacks, but this possible transmission needs further study (Jones et al, 2006b).
Brooks challenges Krkosek and Morton’s work as they go back and forth in their debate, each side minimizing the other’s assumptions. In 2005, Brooks responded to Krkosek’s rebuttal by stating that his literature does not take into consideration the life cycle of sea lice and the ideal/adverse living conditions present during his studies. In 2008 Brooks further states that pink salmon are highly variable in the area and that Krkosek should not have excluded major pink salmon producing systems in his analysis. Brooks also questions the mathematical model Krkosek used.
Even though the research debate is still ongoing, the pro-farm group has not disproven that sea lice is reducing numbers, just that the evidence does not necessarily point to substantial losses and therefore drastic action may not be necessary. This is not in line with the precautionary principle (Lauck, Clark, Mangel & Munro,1998). If Krkosek and Morton are correct, it may be too late to effective counter this threat of extinction or drastically reduced numbers. It is clear that the adaptive management being employed by the BC Government is not effectively managing farmed nor by extension wild fishery numbers (BC Government). The provincial and especially federal governments’ tacit support of fish farms by failing to act according to precautionary principles means that for the time being, change will not be demanded from lawmakers. With this in mind, it is important to minimize the risks to the environment.
Among all of this scientific study, which is meant to divorce emotion from the debate and look exclusively at the evidence uncovered, the 'Namgis ‘non-scientific’ observations become ever more important. They are the people who are directly impacted by these events and ongoing debates. The 'Namgis have long held disdain for the atrocious management of fisheries within their territories and the apparent abandonment of the Broughton Archipelago. This has prompted the 'Namgis to fill the research and management gaps left by the DFO, while simultaneously fighting for guaranteed fisheries access and decision-making powers over their territories ('Namgis First Nation). The 'Namgis have considered the concerns of members employed by local salmon farms and believe that they will be just as useful working on closed containment farms. Although a majority disagrees with the industry’s current operations, split opinions start to occur in some communities where employment levels (economic need) start to outweigh the negative impacts of sea farms (Gerwing & McDaniels, 2006).
Recommendations
There are scientists that wish to debate the potential causes that may be attributable to other factors. It is also understood that the entire salmon fishing industry and its supporters have much invested in the form of employment, public relations, government remittances in the form of taxes and the brand of farmed salmon itself (BC Salmon Farmers Association). It is clear that this is a sometimes emotional issue that has polarized communities. In considering recommendations, the first question needed to be asked is: are farmed salmon capable of being sustainable in its current form? The short answer is no. There are many actions that must be taken to alleviate environmental stresses and to turn the industry into a sustainable, profitable business. It is important to understand that salmon itself is not sustainable. As a carnivorous species, salmon consume 3-3.5kg of fish meal for every 1kg of salmon that reaches market (Naylor, 2000). To give an example of the resources needed, the European salmon farming industry needs an area for feed estimated at 40,000 to 50,000 times the surface area of farms, which is equal to about 90% of the primary production of the fishing area of the North Sea (Naylor, 2000).
We must look at lower trophic level fish species that are herbivorous and require fewer resources to grow such as carp, tilapia and catfish. Countries should encourage production of fish other than shrimp and salmon that are fed diets containing little or no fishmeal (Skretting, 2008) and since there currently is a huge market for salmon that is not abating, several things must be done to minimize the current impacts. Scientists need to research alternative ways to reduce the fish meal, fish oil and heavy usage of energy inputs that are needed, possibly toward natural and safe plant proteins (Skretting, 2008), while simultaneously establishing fines that reduce escapes and increasing regulation of environmental safety measures like feed and drug usage as well as the recirculation of waste water (Naylor et al, 2000). Studies demonstrate a correlation between fallowing farm sites and a decline in numbers of copepodids on wild pink/chum juveniles within 1 km of farms and although further studies need to be done, fallowing farms along migratory routes should be a mandatory measure until proven otherwise (Morton & Routledge, 2005).
Sea lice have a negative impact on wild salmon and must be addressed immediately. Salmon are a keystone species and the reduction of wild salmon has wide implications to the surrounding ecosystems (Willson & Halupka, 1995). Until sustainable alternatives have been implemented, Slice treatments must happen weeks before March 1 to reduce sea louse numbers (Orr, 2007). It is important to move regulation away from industry self-policing and have government staff conduct increased and continual random checks without any notice to salmon farm operators. It is hoped this will maintain the highest of standards until more efficient means are implemented.
The 'Namgis want the farms to be land-based, close contaminant tanks ('Namgis First Nation; The Province, February 24, 2008), which could be publically funded to help with the transition. This has support among environmentalists and the Special Committee on Sustainable Aquaculture (British Columbia, 2007), but is thought of as too costly by the BC Salmon Farmers Association and industry. During this transition, biological barriers should be implemented that separates farmed salmon from the surrounding ocean, while a moratorium on any new farm licenses should be put into place. Designs should be energy efficient and process all wastes. The benefits of closed containment include an ‘eco-salmon’ marketing opportunity, substantial food savings, and control of growing conditions such as temperature, disease and water chemistry (Georgia Strait Alliance & David Suzuki Foundation, 2008). Major hurdles to overcome are the substantial start-up costs, cleaning (in a tank system), as well as ongoing energy costs and impacts (Canadian Geographic). Despite these concerns, there have been many examples of viable closed containment fish farming and with appropriate government support, the salmon farm industry will be able to transition to a more environmentally sustainable operation.
References
'Namgis First Nation. Marine Resources. Retrieved November 27, 2008, from http://www.namgis.bc.ca/resource/Pages/Fisheries.aspx
BC Salmon Farmers Association. Retrieved November 28, 2008, from http://www.salmonfarmers.org/
British Columbia. Adaptive Management. Retrieved November 28, 2008, from http://www.for.gov.bc.ca/hfp/amhome/Admin/index.htm
British Columbia. (2007) Legislative Assembly. Special Committee on Sustainable Aquaculture. Special Committee on Sustainable Aquaculture final report, Third Session, Thirty-Eighth Parliament Legislative.
Beamish, R., Jones, S., Neville, C., Sweeting, R., Karreman, G., Saksida, S. &
Gordon, E. (2006a). Exceptional production of pink salmon in 2003/2004 indicates that farmed salmon and wild Pacific salmon can coexist successfully in a marine ecosystem on the pacific coast of Canada. ICES J. Mar. Sci., 63, 1326–1337.
Bjorn, P. & Finstad, B. (1999). The development of salmon lice (Lepeophtheirus salmonis) on artificially infected post-smolts of sea trout (Salmo trutta). Canadian Journal of Zoology, 76, 970-977.
Brooks, K., Mahnken, C. & Nash, C. (2002). Environmental Effects Associated with Marine Netpen Waste with Emphasis on Salmon Farming in the Pacific Northwest, in Responsible Marine Aquaculture. CAB International.
Brooks, K. (2005). The effects of water temperature, salinity and currents on the survival and distribution of the infective copepodid stage of sea lice (Lepeophtheirus salmonis) originating on Atlantic salmon farms in the Broughton Archipelago of British Columbia. Reviews in Fisheries Science 13, 177-204.
Brooks, K. & Jones, S. (2008). Perspectives on Pink Salmon and Sea Lice: Scientific Evidence Fails to Support the Extinction Hypothesis. Reviews in Fisheries Science, 16(4), 403–412.
Gray, M. Raising a Fish Out of Water: A look at Canada's only land-based salmon farm that's taking small fry to full-sized. Canadian Geographic. Retrieved November 28, 2008 from http://www.canadiangeographic.ca/
Costello, M. (2006). Ecology of sea lice parasitic on farmed and wild fish. Trends Parasitol, 22, 475–483. DOI:10.1016/j.pt.2006.08.006).
Cranmer, G. (1998). The Salmon People of Alert Bay Proceedings of the 12th International Abashiri Symposium, Abashiri, Japan.
Foreman, M., Stucchi, D., Zhang, Y. & Baptista, A. (2006). Estuarine and Tidal Currents in the Broughton Archipelago. Atmosphere-Ocean, 44 (1), 47–63.
Gerwing, K., & McDaniels, T. (2006, March). Listening to the Salmon People: Coastal First Nations' Objectives Regarding Salmon Aquaculture in British Columbia. Society & Natural Resources, 19(3), 259-273. Retrieved November 27, 2008. DOI:10.1080/08941920500460864.
Harvey, B. (2008a, February). Science and Sea Lice: What do we Know? B.C. Pacific Salmon Forum.
Harvey, B. (2008b, October 20). On science, sea lice and sitting on the fence: Biologist believes there's more to issue of salmon farming than easy generalities. Times Colonist. Retrieved November 28, 2008, from http://www.canada.com/victoriatimescolonist/index.html
Heaslip, R. (2008). Monitoring salmon aquaculture waste: The contribution of First Nations' rights, knowledge, and practices in British Columbia, Canada. Marine Policy, 32(6), 988-996. ISSN 0308-597X, DOI: 10.1016/j.marpol.2008.02.002.
Georgia Strait Alliance & the David Suzuki Foundation on behalf of CAAR (2008, May). Global Assessment of Closed System Aquaculture. Ecoplan International Inc. Retrieved November 28, 2008 from http://www.farmedanddangerous.org/
Gillibrand, P. & Willis, K. (2007). Dispersal of sea louse larvae from salmon farms: modeling the influence of environmental conditions and larval behavior. Aquatic Biology, 1,63-75.
Jones, S, Prosperi-Porta, G., Kim, E., Callow, P. & Hargreaves, N. (2006b). The occurrence of Lepeophtheirus salmonis and C. clemensi (copepoda: caligidae) on three-spine stickleback Gasterosteus aculeatus in coastal British Columbia. J. Parasitol, 92, 473–480.
Jones, S., Fast, M., Johnson, S. & Groman, D. (2007). Differential rejection of Lepeophtheirus salmonis by pink and chum salmon: Disease consequences and expression of proinflammatory genes. Diseases of Aquatic Organisms, 75, 229–238.
Krkošek, M., Lewis, M., Morton, A., Frazer, L. & Volpe, J. (2006). Epizootics of wild fish induced by farm fish. Proceedings of the National Academy of Sciences of the United States of America, 103, 15506-15510. DOI:10.1073/pnas.0603525103.
Krkošek, M., Ford, J., Morton, A., Lele, S., Myers, R. & Lewis, M. (2007, December). Declining Wild Salmon Populations in Relation to Parasites from Farm Salmon. Science, 318(5857), 1772. DOI: 10.1126/science.1148744.
Lauck, T., Clark, C., Mangel, M. & Munro, G. (1998, Feb). Implementing the Precautionary Principle in Fisheries Management Through Marine Reserves. Ecological Applications, 8(1), S72-S78.
Morton, A., Routledge, R., Peet, C., & Ladwig, A. (2004). Sea lice (Lepeophtheirus salmonis) infection rates on juvenile pink (Oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon in the nearshore marine environment of British Columbia, Canada. Canadian Journal of Fisheries and Aquatic Sciences, 61(2), 147-157. Retrieved November 29, 2008, from CBCA Reference database.
Morton, A., Routledge, R. & Williams, R. (2005, August). Temporal Patterns of Sea Louse Infestation on Wild Pacific Salmon in Relation to the Fallowing of Atlantic Salmon Farms. North American Journal of Fisheries Management, 25(3), 811-821.
Naylor, R., Goldburg, R., Primavera, J., Kautsky, L., Beveridge, M., Clay, J., Folke, C., Lubchenco, J., Mooney, H. & Troell, M. (2000, June). Effect of Aquaculture on World Supplies. Nature, 405, 1017-1024.
Orr, C. (2007). Estimated Sea Louse Egg Production from Marine Harvest Canada Farmed Atlantic Salmon in the Broughton Archipelago, British Columbia, 2003–2004. North American Journal of Fisheries Management, 27, 187–197. DOI: 10.1577/M06-043.1.
Pacific Fisheries Resource Conservation Council (PFRCC). (2002, November). 2002 Advisory: the Protection of Broughton Archipelago Pink Salmon Stocks. PFRCC, Vancouver. Retrieved November 27, 2008 from www.fish.bc.ca/
Richmond, C., Elliott, S., Matthews, R. & Elliott, B. (2005, December). The Political Ecology of Health: Perceptions of Environment, Economy, Health and Well-Being Among `Namgis First Nation, Health & Place, 11(4), 349-365. ISSN 1353-8292, DOI: 10.1016/j.healthplace.2004.04.003.
SEPA. (1999). Emamectin benzoate - an environmental risk assessment. Scottish Environmental Protection Agency Fish Farm Advisory Group.
Skretting. (2008, September 28). Skretting Fed Salmon Yield More Fish Protein Than They Consume. Retrieved November 28, 2008, from http://www.skretting.com/
Statistic Canada. (2004). Aquaculture, Production and Value, Annual: Detailed Information for 2003. Statistic Canada, Ottawa.
Stone, J., Sutherland, I., Sommerville, C., Richards, R., & Endris, R. (2000, May). The Duration of Efficacy Following Oral Treatment with Emamectin Benzoate Against Infestations of Sea Lice, Lepeophtheirus salmonis (Krøyer), in Atlantic salmon Salmo salar L. Journal of Fish Diseases, 23(3), 185-192. Retrieved November 29, 2008. DOI:10.1046/j.1365-2761.2000.00233.x.
The Province. (2008, February 24). A sea-friendly way to farm fish: salmon in Closed Containers Won’t Interfere with Natural Stocks. The Province. Retrieved November 27, 2008 from http://www.theprovince.com/
Waddy, S., Burridge, L., Hamilton, M., Mercer, S., Aikon, D. &Haya, K. (2002). Emamectin benzoate induces molting in American lobster, Homarus americanus. Canadian Journal of Fisheries and Aquatic Sciences, 59, 1096-1099.
Watershed Watch Salmon Society. (2004). Sea Lice and Salmon: Elevating the Dialogue. Watershed Watch Salmon Society. Retrieved November 25, 2008 from http://www.watershed-watch.org
Willson, M. & Halupka, K. (1995, June). Anadromous Fish as Keystone Species in Vertebrate Communities. Conservation Biology, 9(3), 489-497.