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John Volpe Biological Sciences University of Alberta jvolpe@ualberta

Science Friction: The incredible story of Atlantic salmon in British Columbia. John Volpe Biological Sciences University of Alberta jvolpe@ualberta.ca http://www.biology.ualberta.ca. 1999 Production. 46,738 tonnes dressed (capture fishery all spp. 30,200 t)

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John Volpe Biological Sciences University of Alberta jvolpe@ualberta

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  1. Science Friction: The incredible story of Atlantic salmon in British Columbia John Volpe Biological Sciences University of Alberta jvolpe@ualberta.ca http://www.biology.ualberta.ca

  2. 1999 Production 46,738 tonnes dressed (capture fishery all spp. 30,200 t) $347M farm gate (capture fishery$53M) 81% Atlantic salmon Largest agricultural export product (77%) in BC - 4th largest salmon producer in the world

  3. Atlantic salmon in BC. Why? • Faster growth and feed conversion • Docility • Larger market • Better price • Knowledge base

  4. 1905 5.5 - 13.2 M eggs + alevins released in B.C. Interspecific agonism (ST) 10 resistance factor 1934 Import of AS eggs for aquaculture 1984 1987 First capture of AS in B.C. waters 1991 First reported escape of AS 1995 SAR initiated 1997 SAR released First Atlantic salmon research on Pacific coast initiated ????? 2002

  5. According to DFO’s ASWP 396,552 Atlantic salmon have been reported as escaped 1991-2001

  6. Escapes • 0.5 – 1% of cage population lost via “leakage” (not reported) • Therefore in 1999 • 55,400 – 110,800 Atlantic salmon + (~443,200) • 12,650 – 25,300 Chinook + (~101,200) • 2,900 – 5,900 Coho + (~23,600) • sub-adults escaped in addition to the 35,730 reported • Atlantic salmon escapes. • Only rough estimates of fish on • on hand • Holes in nets a constant • problem • Reporting of escapes is • voluntary Actual number of escapees per year = UNKNOWN

  7. Recoveries 7833 Atlantic salmon reported captured in BC marine waters and 145 Atlantic salmon reported in BC fresh waters in 2000 Like escapes, recovery reports are voluntary. No work has ever been conducted to evaluate the precision or accuracy of these data – however it is widely accepted these numbers do not represent reality. Continued use of these “estimates” sets a dangerous precedent for reliance on fictitious data.

  8. Two major farm escapes in summer 2000 DFO’s passive ASWP = 7833 AS; All BC marine waters, whole year How many captures if there were no openings? 15 day active survey in only Area 12 = 10,826 AS (+41%)

  9. 58 m channel • Variable habitat • 30 females; 20 males • transplanted without • acclimatization

  10. Spawning Chronology Little Qualicum Atlantic Salmon Chum Sockeye Steelhead Sept Oct Nov Dec Jan Feb Mar Apr May Pink Coho Chinook Wild Atlantic salmon in native range

  11. Tsitika River August 18 1998

  12. 0+ 1+ • Natural reproduction • Two year classes present (0+ & 1+) • ~50 juveniles identified to date • Sympatric with strong steelhead population • 0+ AS > ST (50%) 1+ AS >> ST (125%)

  13. Feral Atlantic Salmon populations in Vancouver Island Rivers N 100 km Port Hardy Tsitika R. Amor de Cosmos Cr. Eve R. Campbell R. << 0.01% suitable habitat surveyed Port Alberni Nanaimo Tofino Victoria

  14. Atlantic salmon have been reported in 79 BC streams and rivers Atlantic salmon are now part of the terrestrial food web via predation

  15. What we know so far... • 10’s - 100’s K escaping annually • Significant marine survival • - commercial fisheries, Alaska fresh water captures • Adults ascending all major drainages on Vancouver Island • Production fish will spawn to produce viable • offspring and may do so during low native spawner density • Feral progeny are capable of persisting with steelhead But, Why did historical AS introductions fail?

  16. Wetted area: 2.2m x 0.6m x 0.9 m Coarse river cobble (19.4  5.6cm) ~ 10% replacement per hour Flow 0.85 ms-s (4542.5 L min-1) 10 hp centrifugal pump Water temp maintained by a 240V, 60amp chiller Clear Lexan viewing windows Natural prey provided by a unique “upweller” feeding system

  17. Treatments • High / low forage • Density • Intra- / interspecies comp. • Assembly of “community” Response Variables aSA aAA assembly • Growth • Foraging • Agonism (action + result) • Territory size aAS aSS High Forage 4 AS 4 AS 4 ST 4 ST 4 ST 4 AS 4 AS 4 AS 4 ST 4 ST Low Forage 4 AS 4 AS 4 ST 4 ST 4 ST 4 AS a = comp. coefficient (Δ g) A = Atlantic salmon S = Native Steelhead 4 AS 4 AS 4 ST 4 ST

  18. ST engage in agonism 5:1 over AS ST show intraspecific bias 2 : 1 AS show interspecific bias 2.2 : 1 Residents with 3 days prior residency performed better than challengers under all conditions A significant “residency effect” was observed in both species

  19. N Amor de Cosmos Cr. Study Site From Bear Lake (2km) ST Control Site (ST Only) ST 50 m Small Falls AS ST Experimental Site (AS & ST) To Straight of Georgia / Inside Passage (~3km) 86.5 hrs behaviour data

  20. ST - ST aggression 11.8 x > ST - AS • ST-ST aggression was significantly higher with AS • ST horizontal range on average 9 x > AS • ST - ST aggression > 3x AS - AS; • but AS - ST aggression >2x ST - AS

  21. Vertical Partitioning 1.0 0.8 0.6 Proportion > 10cm 0.4 0.2 0.0 Steelhead Atlantic Salmon

  22. 75 ** 50 Foraging efficiency % 25 0 Foraging 10 5 ** Foragingattempts per 5 min 0 Atlantic Salmon Steelhead Experimental Steelhead Control

  23. Atlantic salmon in Competition - residency + residency Perform well relative to steelhead Perform poorly relative to steelhead 1905-1934: Very low likelihood of establishing prior residency in Vancouver Island rivers Today: Vancouver Island steelhead populations are at ~ 10 - 20% of historical abundance  Potential for successful colonization is likely much higher today than during historical intentional introductions But,

  24. Inputs and outputs “What are the impacts of salmon farming on the sea floor below fish pens? Salmon farms occupy a very small percentage of BC coastal waters, so the habitat affected is also very small. If placed side by side, all the salmon farm sea cages would occupy only about 70 hectares, less space than the new runway at Vancouver International Airport.” BC Salmon Farmers Assoc. web page

  25. TSS allocation for 4 Salmon Farms Bremerton, WA Seattle (830k people) Filtration & Sterilization (US$536M build US$80M / yr.) No Filtration & Sterilization US$0  5.2 M lbs. feces 4 M lbs. TSS Effects of effluent generated at BC’s 104 active farms is unknown Dr. Arthur Whitely U. of Washington

  26. Outputs Antibiotics Pass through the net cage intact or in feces are ingested in low chronic doses by benthos 6.4 tonnes used in 1998 Effects: - generation of “superbugs”; transfer across individuals possible, including to humans - significant alteration of sediment species composition affecting nutrient cycling Pesticides Neurological disruptors used to control sea lice Effects: - Lethal to crustaceans (zooplankton, shrimp, crab etc.) and other fauna including polychaetes and starfish Irish farm company being sued Copper Toxic net treatments to kill fouling organisms Effects: - Undetermined

  27. Inputs Organic Salmon, unlike all other cultured “farm” animals (save shrimp) are carnivorous – feed is 45% fishmeal and 25% fish oil. 2.8 kg wild fish to produce 1 kg farm fish (equivalent by-catch)  The marine area required to produce the feed consumed in a salmon farm is 40,000 to 50,000 times the production area The European industry (production leaders) consume the equivalent of 90% of the North Sea’s 1o production Naylor et al. 2000. Nature 405: 1017-1024

  28. Herring; Mackerel; Anchoveta; Anchovy; Sardinella. • South American oceans being mined at tremendous rates to • satisfy northern hemisphere demand for fish meal in the • production of a luxury product. • Many of these fisheries are in a state of collapse forcing • commercial fishers to target species even lower in the food • web, further aggravating the problem. • Currently a salmon glut on world market. Commercial salmon • fishers must now catch more wild salmon to maintain historical • earnings

  29. Outputs The Product Feed contaminated with PCBs Polycyclic aromatic hydrocarbons (PAH) - genotoxin / mutagen Polybrominated biphenyl ethers (BPDE) - flame retardant Organochlorine pesticides (OPs) # of servings of BC farm salmon required to exceed WHO guidelines: 1.5 / week Easton et al. 2002. Chemosphere 46: 1053-1074

  30. Inputs Energy Tyedmers 2001. PhD Thesis, UBC

  31. Tyedmers 2001. PhD Thesis, UBC

  32. Sea Lice

  33. Sea lice are native however the density of farms may act as bio-magnifiers of parasites and disease such that the migratory habitat becomes saturated ie. pink smolt run

  34. Pink salmon smolts June 2001

  35. Natural Selection “Normal curve” “Nothing in biology makes sense except in the light of evolution“ Theodosius Dobzhansky Proportion of Population Character Trait (e.g. Aggression)

  36. Escape Spawn Wild Farm Proportion of Population High Low Aggression

  37. Second feral generation displays appropriate levels of aggression - much greater performance and survivorship. Wild Proportion of Population High Low Aggression

  38. Escapees selected for “wild type” behaviours and traits Treatments for parasites and diseases “select” for resistant and more virulent strains – passed back to wild populations (Anti bacterial soaps - “97% effective”) Processes are likely to change as fast, or faster, than we are capable of describing them.......

  39. Is there a plan? How many escaped Atlantic salmon are too many? What infestation rate of sea lice on native salmonids is too high? How much industrial waste is too much? Etc....etc.....etc..... Is salmon aquaculture so different from other industrial activities that threshold effects on the environment are unnecessary?

  40. 1) all reasonable actions must be taken to protect the environment 2) inherent to this statement is the understanding of “reverse onus” - the burden of proof lies with industry to satisfactorily demonstrate their activity is not detrimental to the environment. The burden is not on the public to demonstrate the opposite

  41. Research Assistants Dr. Brad R. Anholt - UVic Biology Dr. Barry W. Glickman - UVic CEH Chris Borkent Rick Ferguson Jeff Hopkins Ian Jacobs Megan Kaneen Tye Lougheed Steve Martin Dan O’Neil Emily Rubidge Malcolm Wyeth Gerry Horne - UVic Aquatics Facility Funded by: B.C. Habitat Conservation Trust Fund B.C. Min. Fisheries

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