Dr. John Volpe Biological Sciences University of Alberta jvolpe@ualberta.ca

1. Testing assumptions associated with farm-escaped Atlantic salmon in British Columbia Dr. John Volpe Biological Sciences University of Alberta jvolpe@ualberta.ca

2. Issues • Visual pollution (ecotourism) • Site contamination (organic & pharmacological) • Anti predator methods • Disease transfer to / from wild salmonids • Ecological consequences of escapees

3. 1905 5.5 - 13.2 M eggs + alevins released in B.C. Interspecific agonism (ST) 10 resistance factor 1934 Import of S. salar eggs for aquaculture 1984 1987 First capture of S. salar in B.C. waters 1991 First reported escape of S. salar 1995 SAR initiated 1997 SAR released First Atlantic salmon research on Pacific coast initiated Phase I research complete 2001

4. The Explanation Cascade • Escapes of Atlantic salmon are rare • Escapes of Atlantic salmon are inevitable but they won't survive in the wild • Some Atlantic salmon may survive but will not ascend freshwater rivers • Some adult Atlantic salmon are likely to be found in freshwater rivers but can't spawn • Spawning is likely to occur but progeny will not be competitively viable And finally, the current position, • There is no scientific evidence to show that the presence of feral juvenile Atlantic salmon in some rivers pose a threat to native populations.

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

7. The Explanation Cascade • Escapes of Atlantic salmon are rare • Escapes of Atlantic salmon are inevitable but they won't survive in the wild • Some Atlantic salmon may survive but will not ascend freshwater rivers • Some adult Atlantic salmon are likely to be found in freshwater rivers but can't spawn • Spawning is likely to occur but progeny will not be competitively viable And finally, the current position, • There is no scientific evidence to show that the presence of feral juvenile Atlantic salmon in some rivers pose a threat to native populations.

8. Atlantic salmon are commonly part of commercial salmon catches from Alaska to Washington No data are available regarding the source of these fish (physical or DNA tags) or period since escape and performance in the interim (otolith microstructure / stable isotope analyses)

10. Atlantic salmon have been reported in 77 BC streams and rivers Atlantic salmon are now part of the terrestrial food web via predation

12. Tsitika River August 18 1998

13. 58 m channel • Heterogeneous habitat • 30 females; 20 males • transplanted without • acclimatization

14. 1/3 females spawned • Spawning initiated • in mid January

15. 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

16. 0+ 1+ • Natural reproduction • Two year classes present (0+ & 1+) • ~50 juveniles identified to date • Sympatric with strong steelhead population

17. 0+ AS 0+ ST 1+ AS 1+ ST Mean Fork Length (mm) 63.75 ±3.3 55.42 ±5.81 119.25±5.52 92.59±10.46 Mean Weight (g) 2.94±0.60 1.91±0.5419.61±4.01 8.67±2.75 Mean CF (g x 100)/cm3 n 1.12 1.16 1.12 1.10 4 33 8 33

18. Feral Atlantic Salmon populations in Vancouver Island Rivers N 100 km Port Hardy Tsitika R. Amor de Cosmos Cr. Eve R. Campbell R. <1% potential spawning and rearing habitat has been surveyed on Vancouver Island. Coastal mainland systems remain entirely uninvestigated.......? Port Alberni Nanaimo Tofino Victoria

20. 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

21. Treatments • High / low forage • Density • Intra- / interspecies comp. • Assembly of “community” Response Variables • Growth • Foraging • Agonism (action + result) • Territory size High Forage 4 AS 4 AS 4 ST 4 ST 4 ST 4 AS 4 AS 4 AS 4 ST 4 ST aAA aSA assembly 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 aAS aSS

22. ST on average engage in agonism 5:1 over AS ST show agonistic bias towards other steelhead 2 : 1 AS show bias towards steelhead 2.2 : 1 Therefore, steelhead are agonism targets, Atlantic salmon are not

23. Of all treatment combinations the only consistent and significant predictor of performance is assembly order Residents with 3 days prior residency performed better than challengers under all conditions - regardless of all other parameters

26. Atlantic salmon - 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

27. At present YES Are production fish capable of spawning? YES Are juvenile Atlantic salmon competitively viable? YES (qualified) Are such conditions present in coastal B.C.? Historically NO Sufficient spawner densities for natural reproduction? YES Presence of feral populations? YES (3) Feral individuals perform as predicted? YES Prognosis?

29. Pink salmon smolts June 2001

30. 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

32. There is no scientific evidence to show that the presence of feral juvenile Atlantic salmon in some rivers pose a threat to native populations. There is no evidence that salmon aquaculture as currently practiced in BC will not result in serious harm to native salmon populations or their environment.

33. 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