Fraser River sockeye salmon: data synthesis and cumulative impacts

Response: This section has been completely rewritten, and we have introduced ourquantitative methods in plain language in section 3.3.6.19. Page 60 - The exceptional case of the Harrison River sockeye should be movedfrom its current hidden location at the end of point 4 and put into its own point. This willenable you to emphasize the importance of the evidence that could be gleaned fromstudying that stock more thoroughly, given that its life history is quite different from otherFraser sockeye stocks.Response: We have moved comments on the Harrison stock into their own bullet point toemphasize that stock-specific knowledge of its migration route and timing would beespecially useful given its unique life history and productivity trends (i.e., the only stockwith increasing productivity).20. Page 61 - I would add a new point under "Key things we need to know better" thatwould specifically state the need to take the current knowledge about consumption ratesof sockeye salmon and other species by marine mammals, the bioenergetics of thosemammals along with their population sizes, and combine these into estimates of totalconsumption of sockeye salmon by populations of a given species of marine mammal.For too long now, this last step has been missing, yet it should be easy to calculate arange of estimates given a standard set of assumptions like those that Christensen andTrites apparently used for their spiny dogfish example described on page 53.Response: We agree with the reviewer’s comment and have added this recommendationunder “Key things we need to know better”. This recommendation has the advantage ofbeing fairly specific and preliminary efforts could be initiated immediately with theinformation currently available.21. In the context of the previous comment, lines 8-10 on page 62 make a statementthat is inconsistent with the point made on page 53 about the total potential impact ofspiny dogfish predation on salmon, despite salmon being a tiny portion of the diet of thedogfish. The offending sentence is: "On the return journey back to the Fraser, there aremany marine mammals that will prey on adult salmon, but sockeye salmon do notappear to be a substantial portion of any of their diets". Surely, the authors have to beconsistent in their logic and say the same thing about the marine mammals as they didfor the spiny dogfish.Response: We have revised this section.22. The line in Figure 4.5-2 does not seem to be the best-fit line; visually at least, itseems like it should have a lower slope. What was the assumption about the error termin the fitting method?Response: This graph was extracted as an image from the publication cited and thereforethe “trend” line could not be removed. We were not able to acquire the underlying data127