ANS18-10-L15-SALMON-ENV-HEALTH - Salmon Culture – Value...

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Unformatted text preview: Salmon Culture – Value U.S. • Salmon farming – 7th globally; ~ 11% of the value of the U.S. aquaculture industry • 45 commercial farms – food fish • In addition 244 federal, state, or tribal facilities produce anadromous Pacific and Atlantic salmon for restoration of commercial fisheries • globally 5 billion smolts produced annually • > 300 freshwater facilities producing salmonids (mostly trout species) for recreational fishing. ANS 18 - SALMON 1 ANS Concerns over possible impact of farmed salmon on wild stocks of Pacific salmon ANS 18 - SALMON ANS 2 Environmental Concerns - ANS 18 - SALMON ANS 3 Salmon farm with 1 acre of pens (~ 1 football field) produces about 20,000 fish annually. That equates to: 220,000 lbs of 5 kg fish (with ~ 0.7 kg of solid waste/ kg of salmon) or 1,375 people (160 lbs @) with the appropriately sized sewage treatment plant ANS 18 - SALMON ANS 4 Benthic Pollution • Salmon farms versus sewage plants – Impact area far less and wastes do not contain metals and industrial hydrocarbons as do wastes from a sewage treatment plant – Reformulation of feeds to reduce zinc pollution – Biological remediation of a fish farm site = 5 months to several years; sewage treatment plants > 10 years. ANS 18 - SALMON ANS 5 Benthic Pollution • Salmon farms versus fish processing plants – at current levels of production all the salmon farms in Puget Sound produce a cumulative total of ~ 5,000 mt of biosolids. – In comparison, an individual seafood processing plant might discharge 20,000 – 30,000 tons of organic material per year. – A waste pile at one plant was estimated to be 200 m in diameter and 7 m deep. However, NMFS found such waste piles appear to have only localized impact and do not adversely affect threatened or endanger species. ANS 18 - SALMON ANS 6 Flushing • Poorly flushed sites – high production plus net cleaning – impacts 30 m from net perimeter • Well flushed sites – farms stimulate infaunal community throughout the area. ANS 18 - SALMON ANS 7 Nitrogen Wastes • No problem? – The additional dissolved nitrogen added to the water column by salmon farms is not measurable more than 9 m away from the net pens. – Clam Bay – farm raising 3 million salmon/year; no effect on EPA oyster larvae bioassay, poor place to grow mussels because of low algal levels. • Toxic algal blooms – ANS 18 - SALMON ANS 8 Dissolved Oxygen Maximum reduction in water passing through a net-pen 2 ppm (typical ~ 0.5 ppm. Salmon require > 6 ppm. Environmental waters with low oxygen levels impact more often on the net-pens than the other way around. ANS 18 - SALMON ANS 9 Disease • No evidence of salmon to human transfer of diseases • Specific diseases and prevalence in Atlantic salmon stocks cultured in netpens in Puget Sound are no different than those of the more numerous culture stocks of Pacific salmon in hatcheries. • Drugs used in Atlantic salmon net-pen culture are the same array as used in Pacific salmon hatcheries. ANS 18 - SALMON ANS 10 Salmon diseases • 9 major viral and bacterial diseases – Development of vaccines • Management (Best Practices) – ISA (infectious salmon anemia virus) • 2010 - Chile will only produce 250,000 mt (down from ~ 400,000 mt in 2008) ANS 18 - SALMON ANS 11 Industry response to disease • Development of vaccines has dramatically reduced the use of antibiotics in countries such as Norway To their regret, producers in the southern hemisphere feeling that without wild salmon they would not have any disease, the industry has ignored best management practices such as spacing between farm sites and not dumping processing wastes near farm sites. The Norwegian salmon industry is extremely saddened by the troubles presently facing the industry in Chile. ANS 18 - SALMON 12 ANS • A potential problem for nearby wild salmon • Best management practices to Parasites – Sea Lice deal with sea lice are: – Routine monitoring – Targeted treatment to maintain low infestation rates – Coordinated chemical treatments for neighboring farms – Year class separation – Fallowing of culture areas to break lice cycles ANS 18 - SALMON ANS 13 Color added • FDA ruled grocery outlets must label farmed salmon containing astaxanthin as 'color added' under the Federal Food, Drug and Cosmetic Act In fact, all salmon eat food containing a beta-carotene derivative (astaxanthin) retaining the pigment in their flesh. • – Wild salmon eat krill which contain these pigments. – Farm-raised salmon receive the same pigments (typically chemically synthesized) in their feed pellets. ANS 18 - SALMON ANS 14 Which is better to eat? ANS 18 - SALMON ANS 15 Consumer Focus Groups 33 33 compared to 27 Fresher Better Flavor Higher quality 27 Higher price!! ANS 18 - SALMON ANS 16 Fisheries = April – Oct. Aquaculture = year round $ 5 – 12/lb Up to $ 22/lb ANS 18 - SALMON ANS 17 tested salmon sold as wild from by eight New York city supermarkets in March New York Times 4/10/2005 “WILD” PRICE/LB Fishery In stores (March) Up to $ 22/lb April – Oct. 23/25 FARMED $ 5 – 12/lb Year Round - Wide spread in store availability of fresh “wild” salmon surprising given that most wild fisheries were not yet open ANS 18 - SALMON ANS 18 Dye/Feed Additive The varying proportions of three stereoisomers allows for discrimination between natural and chemically synthesized astaxanthin ANS 18 - SALMON ANS 19 tested salmon sold as wild from by eight New York city supermarkets in March New York Times 4/10/2005 “WILD” FARMED Up to $ 22/lb $ 5 – 12/lb PRICE/LB April – Oct. Year Round Fishery 23/25 In stores (March) 2/8 Confirmed as wild i.e. 75% of the salmon being sold in New York city during March as “wild” were actually farmed ANS 18 - SALMON ANS 20 Predator Prevention Anti-predator nets •Seals •Birds ANS 18 - SALMON ANS 21 Fish Escapes • Competition - Ø • Predation - Ø – Stomachs of recovered farm Atlantic salmon and of the few naturally produced Atlantic salmon juveniles show no evidence of predation on other salmon • Hybridization - Ø • Colonization – Atlantic salmon from pens found in 77 streams/rivers in B.C. and 12 streams in Washington State. Naturally produced juvenile Atlantic salmon found in 3 streams in B.C. but none in Washington State (as of yet!) ANS 18 - SALMON ANS 22 Interaction between Atlantic and Pacific Salmon • Direct interbreeding doesn’t seem to be a worry • (it can only be done artificially and even then viability of eggs is low). Establishment of breeding populations of Atlantic salmon along the Pacific coast may reduce habitat needed by Pacific salmon during their freshwater phase of life. – the use of sterile triploids by the culture industry would eliminate the potential for breeding populations being established but there have been no movement in that direction by any government body as of yet. ANS 18 - SALMON ANS 23 Visual Pollution ANS 18 - SALMON ANS 24 Product Advantages Capture Seasonal – “sell or smell it” Size/weight variation Culture Year round – predictable quantities Control of product including color ANS 18 - SALMON ANS 25 Contaminants – chlorinated hydrocarbons ANS 18 - SALMON ANS 26 Control of product “Global assessment of organic contaminants in farmed salmon” R.A. Hites, et al. Science 303: 226-231 (2004). • Farmed salmon had higher levels of chemical contaminants (PCBs) than wild salmon. Wild salmon feed on a variety of organisms and thus their body burden of PCB is less than cultured salmon in which fish meal is the primary protein source. • Farmed salmon from Europe had higher levels of PCBs than farmed salmon from Chile. Pollution is higher in fish used for fish meal around Europe than it is in the Southern hemisphere. • All levels those in farmed salmon were below the level set by the FDA however some feel this level should be lower. ANS 18 - SALMON ANS 27 Control of product See Science 305: 475-478 Letters written in response to “Global assessment of organic contaminants in farmed salmon” R.A. Hites, et al. Science 303: 226-231 (2004). • Risk-benefit analysis of eating farmed salmon indicates the heart healthy benefits of salmon fatty acids is outweighs the tiny worry about PCB’s • No evidence of a problem in Norway from eating farmed salmon • My examination of FAO production data and USDA consumption data suggests consumers don’t feel this is significant risk. ANS 18 - SALMON ANS 28 Industry response to “Global assessment of organic contaminants in farmed salmon” R.A. Hites, et al. Science 303: 226-231 (2004). Control of product - • Reducing the amount of protein in the diet. While they aren’t catfish yet the amount of dietary protein has decreased. • Using protein sources other than expensive fishmeal. Fish meal levels in salmon diets in 1995 was 45% in 2007 it was only 24%.s Fish oil, also a source of contamination declined from 25% to 16% over the same period. • Future trends • Wild salmon – What they are is what you get. • Farmed salmon – Less and less contamination even though it is now below FDA levels and the public doesn’t seem to care. As the industry moves away from fish meal and fish oil contamination levels will become less and less. ANS 18 - SALMON ANS 29 Market displacement of wild salmon (& fishermen) Atlantic salmon On farm price 1988 ANS 18 - SALMON ANS 2002 1.21/lb 30 3.11/lb Product Advantages Capture Seasonal – “sell or smell it” Size/weight variation Culture Year round – predictable quantities Control of product including color “new & improved” product Vertically integrated companies large retailers 31 Numerous small sources processors wholesales large retailers ANS 18 - SALMON ANS Farming will become more and more efficient ANS 18 - SALMON ANS 32 • Size • Cut • Boneless • Color • Contaminant free • Happy fish?? (see next slide) “What ever the customer wants” The industry can and will provide. At a price, of course!! ANS 18 - SALMON ANS 33 • Scottish salmon - $ 23 – Low density culture ~ 9 mt/ha (“happy” fish) – 1 year of fallowing; natural cleansing and regeneration – Nets, no anti-fouling treatment; high mooring specifications and replacement every two cycles minimize escapes – All feed comes from sustainable non-GM sources • The fishmeal in the diet is derived from the by products (offal/filet trimmings) of pelagic fish caught for human consumption. • Astaxanthin used in the feed is from yeast (phaffia). Seasons Restaurant in Davis – Integrated aquaculture (seaweeds and sea urchins) ANS 18 - SALMON ANS 34 ...
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