Fraser River sockeye salmon: data synthesis and cumulative impacts

constitutes an exposure to human activities. These farms have been shown to besignificant sources of sea lice (Price et al. PloS One, 2011) and they are a potentialsource of viral pathogens (note my emphasis on the word “potential” due to lack of clearevidence that I’m aware of). The impacts of exposure to fish farms on population trendsof Fraser sockeye are not clear, but the exposure of wild out-migrating juveniles tofarms is clear. Salmon farms may have been ignored here because the aquaculturereport is still in progress. If the authors agree with my point, that juvenile sockeye areexposed to a significant human activity in the form of salmon farms, the wording on p.59 should be changed too, as should the Conclusion.Response: The reviewer is correct - salmon farms are not currently included in the presentreport because the aquaculture report is still in progress. When it is completed we willwrite an addendum to our report that qualitatively considers the evidence provided in theaquaculture report. The reviewer raises a reasonable point regarding exposure to salmonfarms in the upper Strait constituting an exposure to human activities. To avoid implyingthat sockeye are not exposed to salmon farms, we have modified the text in both theExecutive Summary and Section 4.5.2 to explicitly clarify that we are only referring tohuman activities covered by Technical Report #12 and not to salmon farms.p. 5 / pdf 13. “It’s also very likely that marine conditions during the inshore migration lifestage contributed to the poor returns observed in 2009.” I would add that it is also verylikely that improved marine conditions (cooler temperatures and associated food webs?)contributed to the improved return in 2010.Response: We’ve added a brief discussion of 2007 vs 2008 (and their implications forreturns in 2009 and 2010) to section 4.4.3, based on McKinnel et al (2011).p. 5 / pdf 13. I am confused by the paragraph called “Stage 5: Migration back toSpawn”. The authors say: “…the Fraser sockeye productivity indices already accountfor en-route mortality (i.e., recruits = spawners + harvest + en-route mortality).” Isuggest starting with a clear definition of what, exactly, is meant by “productivity”, and“recruits”. Productivity can defined as the number of returns per spawner, where a“return” is a fish that comes back to the coast. Further sources of mortality are notincluded, such as fishing and en-route mortality in the river. From parts of the rest ofthe report, including the use of the SFU Think Tank’s figure on p. 21 (pdf 35), I THINKthe authors and I agree that productivity means what I am calling “returns to the coast”per spawner. But in other places I’m not so sure. The definition the authors have usedsuggested to me, the first few times I read it, that they were INCLUDING survivalthrough the fishery and en route mortality as part of the definition of “productivity”. Thatis also implied by their analyses of Recruits/Spawner later in the report. My question is,are different metrics being used to represent “productivity”?Response: We have now clearly and consistently defined productivity in the ExecutiveSummary, Introduction, and Section 4.1. We have applied the term consistently throughoutthe report. Three metrics are explained in Section 4.1, based on Peterman and Dorner159