Fraser River sockeye salmon: data synthesis and cumulative impacts

Staley: Our project needs to compare expenditures in the Canadian context.Routledge: A concern about a focus on science that informs managers in terms of short-termdecisions is that you lose the ability to do fundamental science that provides important longterminsights that filter down to the management level. It should not be too short-sighted.Peterman: You can focus on what is relevant to management but look at what this means overthe long termPeterman: The important issue is how this informs Cohen’s decisions. Bristol Bay stocks have amuch stronger pattern over time, so they are easier to forecast and manage from this andother respects logistically. So we need to be really careful to not compare apples and oranges.English: Our report will highlight how different they are and how complex the Fraser is in termsof the people involved. Alaska managers have full control and simple targets. They spend atiny fraction of the value of the fishery on management and the environmental, socialeconomic and other issues are all very different.Diseases & parasitesMichael Kent, Oregon State UniversityThe task was to report on infectious diseases in general and those affecting Fraser sockeye inparticular and assessing the role of infectious diseases in mortality, especially in wild fish.The approach included a review of peer-reviewed literature, government documents and PBScase reports and interviews with DFO fish health specialists.The study reviewed each pathogen by taxonomic units, including arbitrary (low, medium, high)potential risk assessment for each. It is rare to have a quantitative risk assessment, so it’s a verysubjective approach. Much of the report consists of a summary for each pathogen, plus the riskassessment. It also includes a review of approaches used to document pathogen-associatedmortality in wild fish, a review of environmental associations with these pathogens, conclusionsand recommendationsKey metrics: These include whether the pathogen is virulent to Pacific salmon and to sockeye inparticular; occurrence and prevalence in wild salmon and in the Fraser; how was this determined(literature reviews and interviews); and how these metrics are connected to biologically-justifiedhypotheses.The list of pathogens includes a number of viruses, bacteria, fungi, protozoa, myxozoa, wormsand arthropods. Documented or suspected freshwater outbreaks include IHN virus in fry. In theocean, Parvicapsula is worth looking at (about 15 years ago, there was a report documentingmortality in Barkley Sound pre-spawners – returning fish were trapped and suffered heavyinfection) and sea lice (Barkley Sound prespawners). There are very few documented reports ofmortality specifically caused by parasites or other pathogens in BC, except when you look at prespawningmortality. Work in Oregon on returning fish shows a long list of pathogens associatedwith pre-spawning mortality, with losses of over 50% in some cases.High risk diseases: There are few pathogens documented or suspected of killing Fraser sockeye(ones that are recognized as killing sockeye and suspected of occurring in the Fraser). Theseinclude IHN (freshwater virus); Bacterial kidney disease (freshwater and ocean), Furunculosis(freshwater and ocean) and Vibriosis (marine). There is very little data on how the latter impacts41