The Science is in on salmon farms
– holding large schools of salmon stationary in the ocean breaks biological laws causing local disease/parasites to intensify and infect wild fish at levels they cannot survive.
In the wild when a fish gets sick it begins to slow down and swim at the outer edge of the school. Predators remove these fish from the school, thus disease epidemics in the wild are extremely rare. However when farm fish get infected with sea lice and diseases from the wild fish these pathogens breed and reproduce at exponential rates with no predation. When large numbers of farm fish start dying the companies apply drugs to try and keep some alive to get them to market size. Our enhancement hatcheries must kill sick fish to prevent spreading the disease, but government does not make fish farmers remove sick fish. In 2002-2003 government allowed Norwegian fish farmers to hold 12 million IHN virus infected fish on BC’s largest wild salmon and herring migration, the inside passage of Vancouver Island.
The 2005 Fraser River sockeye
, which collapsed, swam through that epidemic as they went to sea. Steelhead are in decline wherever they migrate through fish farms. Chinook salmon in Clayoquot are collapsing despite excellent river conditions. Broughton pink salmon collapsed until fish farms started reducing their sea lice. Wild salmon and sea trout in Scotland, Ireland and Norway went into steep decline as salmon farms got larger in the fjords and lochs.
Like any tool, science can be misused to suggest that fish farms are not the problem, but these papers are not widely respected outside of the governments that produced them and they certainly do not disprove the findings below. You will see we successfully published rebuttals showing that our results are correct.
For a good overview of how the science around salmon farms has been misreprented, see essay A Canadian Trajedy by Neil Frazer.
1. Morton, A.B. and Symonds, H.K. 2002. Displacement of Orcinus orca by high amplitude sound in British Columbia, Canada.
ICES Journal of Marine Science. 59: 71-80 This paper found resident fish-eating killer whales abandon areas where 198DB acoustic harassment devices were used b fish farmers. We tracked the whales and so know that they still survive, but were displaced from a large forage range. It is against the law in Canada to disturb a whale in this way, but nothing was ever done. Eventually the fish farmers discovered the devices attracted the seals they were trying to repel and they turned the devices off, but the whales have never returned as they cannot risk their hearing, which is their primary sense.
2. Morton, A.B. and Volpe J. 2002 A description of escaped farmed Atlantic salmon Salmo salar captures and their characteristics in one Pacific salmon fishery area in British Columbia Canada, in 2000
. Alaska Fishery Research Bulletin, 9: 102-109. In this study I examined 100s of Atlantic salmon caught by commercial fishermen. I learned that after three weeks of freedom a quarter of the escaped salmon I examined had learned to eat wild food (salmon smolts, herring, shrimp). The industry and government say farm salmon can’t do this. I also found that large very mature Atlantic salmon were hanging around the outside of the pens, probably feeding on escaping pellets. There should be gillnets employed around fish farms to remove these fish as they are the ones most likely to spawn in our rivers, but government and industry have refused to do this. Over 10,000 Atlantics were caught in the 2000 fishing season. Since that time there have been almost no commercial fisheries in the area so I don’t know how many Atlantic salmon are out there now. They are best caught by gill nets and associate with Steelhead while traveling.
3. Morton, A.B., and Williams R . 2003 Infestation of the sea louse Lepeophtheirus salmonis (Krøyer) on juvenile pink salmon Oncorhynchus gorbuscha (Walbaum) in British Columbia,
Canadian Field Naturalist, 117: 634-641 This was my first look at sea lice. When I saw them I contacted Norwegian scientists who told me how to identify the different stages. I contacted DFO, they asked me to catch infected juvenile salmon for them and when I did tried to charge me for fishing without a scientific permit.
4. Morton, A.B., Routledge, R., Peet, C. and Ladwig, A 2004 Sea lice, Lepeophtheirus salmonis, infection rates on juvenile chum and pink salmon in the nearshore marine environment in British Columbia. Canadian Journal of Fisheries and Aquatic Science, 61: 147-157.
In this study we looked at fish collected in many studies as well as our own, coastwide to see if sea lice were occurring along the entire coast of Canada or not. What we found was sea lice were only and always on juvenile salmon near fish farms. A. Ladwig is a DFO employee.
5. Blaylock, R. B. Overstreet, R.M. and Morton, A.B. 2005 The pathogenic copepod Phrixocephalus cincinnatus (Copepoda: Pennellidae) in the eye of arrowtooth flounder, Atherestes stomias, and rex sole, Glyptocephalus zachirus, from British Columbia. The European Association of Fish Pathologists, 25: 116-123. In this study we report on a grotesque abundance of a parasite (link photo) that infects the eye balls of some flat fish near fish farms. It is a natural parasite but occurs in unnaturally high numbers near fish farms
6. Morton, A.B., Routledge, R, and Williams R. 2005 Temporal patterns of sea lice infestation on wild Pacific salmon in relation to the fallowing of Atlantic salmon farms. American Journal of Fisheries Management. 25: 811-821. In this study, we counted sea lice on juvenile pink and chum salmon near fish farms for three years. In the first and third year, there were Atlantic salmon in the farms and there were lots of sea lice on the juvenile wild salmon near the farms. In the middle year, 2003, the Province removed all the farm fish to benefit the pink salmon and there were very few sea lice on the wild salmon. The Province never mandated this again.
7. Krkosek, M., A. Morton, and J.P. Volpe. 2005. Nonlethal Assessment of Juvenile Pink and Chum Salmon for Parasitic Sea Lice Infections and Fish Health. Transactions of the American Fisheries Society. 134: 711 716. In this paper we describe how we count sea lice on juvenile salmon without killing them.
8. Morton, A. B. and Routledge (2006) Mortality rates for juvenile pink and chum salmon (Oncorhynchus gorbuscha and keta) infested with sea lice (Lepeophtheirus salmonis) in the Broughton Archipelago. Alaska Fisheries Research Bulletin. 11:2, 146-152. In this study I caught wild juvenile pink and chum salmon near fish farms and sorted them into flow-through barrels that were submerged in the ocean. The fish were sorted by number of lice so in some barrels there were no lice on the fish, in others there were 1, 2, 3 lice per fish. I cared for them all the same way and after three weeks found the ones with no lice had grown longer and were fat and glossy. Many of the lice died, but if even one louse survived, the fish, all of which were too young to have scales, died. The fish with lice ate much more aggressively trying to feed the lice and their bodies, but eventually they gave up and drifted on the surface and died.
9. Morton, A.B. and Richard Routledge (2006) Fulton’s Condition Factor: Is it a valid measure of sea lice impact on juvenile salmon? North American Journal of Fisheries Management. 26,56–62. Government scientists said lice do not affect the growth rate of young salmon, but in this paper we show that by eating voraciously the little salmon can keep up with the lice for a while, but then give up and float around on the surface where predators can get them. Therefore, in the wild you rarely find the emaciated lice-infected fish all you find are those eating as fast as they can and losing the race against the lice.
10. Krkosek, M., Lewis, M.A., Volpe, J.P., & Morton, A.B.. 2006. Fish Farms and sea lice infestations of wild juvenile salmon in the Broughton Archipelago - A rebuttal to Brooks (2006). Reviews in Fisheries Science. 14: 1-11. In this rebuttal, we show that Brook’s conclusion was based on a ﬂawed interpretation of how salinity affects louse development, a misunderstanding of how the timing of salinity changes corresponds to the timing of the juvenile salmon migration, models of larval dispersion that overestimate the transport of louse larvae, and a selective and misleading assessment of the literature. Therefore we conclude the sea lice infestations on wild salmon near fish farms are coming from the farm fish.
11. Morton, A.B. and Williams, R. 2006. Response of the Sea Louse Lepeophtheirus salmonis infestation levels on juvenile wild Pink, Oncorhynchus gorbuscha, and Chum, O. keta, salmon, to arrival of parasitized wild adult salmon. Canadian Field Naturalist. 120:2 In this paper we count sea lice on juvenile wild salmon near fish farms as wild adult salmon enter the area on their way to spawn. We found the effect of arriving adult salmon was very hard to detect given the lice infestation rates already underway by the farm salmon.
12. Krkosek, M., Lewis, M., Morton, A. Frazer, N., and Volpe, J. 2006. Epizootics of wild fish induced by farm fish Proceedings of the National Academy of Sciences of the USA, 103: 15506-15510. In this paper we report on a comprehensive analysis of the spread and impact of farm-origin parasites on the survival of wild salmon populations. In the wild adult and juvenile salmon are kept separated by the timing of their migrations, but fish farms disrupt this system, holding adult salmon and their lice in the path of juvenile salmon. We found fish farms elevated lice on wild salmon over 80 km around the farms.
13. Krkosek, M., Ford, J. S., Morton, A.B., Lele, S., Myers, R.A., & Lewis, M.A., 2007. Declining wild salmon populations in relation to parasites from farm salmon. Science. 318, 1772-1775.In this paper we report that sea lice from salmon farms were killing approximately 80% of each pink salmon generation and were driving these populations to rapid extinction. (The fish farmers responded with coordinated drug treatments which saved these pinks from extinction, but the impact of the drug on other species is unknown and this and other delousing drugs are becoming ineffective worldwide as the sea lice become drug resistant.)
14. Krkosek, M., Ford, J. S., Morton, A.B., Lele, S., & Lewis, M.A., 2008. Response to comment on 'Declining wild salmon populations in relation to parasites from farm salmon'. Science. 322, 1790-1791. In this article, we respond to concerns raised by Brooks and Jones (2008) about recent advances in sea lice and salmon population dynamics in the Broughton Archipelago, British Columbia. We show that the assessment by Brooks and Jones (2008) is thoroughly mistaken and that their conclusions are based on a combination of obfuscation, misrepresentation, and fundamental misunderstandings. The extinction hypothesis is not actually a hypothesis at all, but rather an inevitable consequence of sustained population decline. Local extinction of Broughton Archipelago pink salmon can be prevented if population declines are turned around, and the data and models suggest this can be achieved if the infestations are stopped.
15. Morton, A.B., Routledge, R. and Krokosek, M. 2008. Sea lice infestation of wild juvenile salmon and herring associated with fish farms off the east central coast of Vancouver Island, BC. North American Journal of Fisheries Management 28, 523-532. In this paper we looked at the relationship between number of sea lice on juvenile pink, chum, sockeye and herring exposed and less exposed to salmon farms in the Discovery Islands and found the same type of relationship as elsewhere. Wherever the fish were near salmon farms they had elevated sea lice numbers.