Fraser River sockeye salmon: data synthesis and cumulative impacts

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(2011).This confusion continues with the logic that since “…the Fraser sockeye productivityindices already account for en-route mortality (i.e., recruits = spawners + harvest + enroutemortality)”, “there is no point in examining correlations between en-route mortalityand life cycle or post-juvenile productivity indices within the same generation.” Well, if“productivity” means “returns to the coast” per spawner, then fishing and en-routemortality are NOT already accounted for, unless the authors mean that they havecalculated these losses back in. This probably just needs to be re-worded to make itmore clear.Response: We believe that the definitions mentioned above clarify this issue.p. 5/19. “If the effects of an individual project are insignificant, it is assumed that theproject’s contribution to potential cumulative effects will also be insignificant and a CEAwill not be required for project approval (Greig 2010b).” Well, maybe, but isn’t the pointof a cumulative effects consideration that insignificant effects can be added or multipliedtogether? Admittedly, such effects would be very difficult to detect.Response: Yes, this is completely true – the cumulative effect of multiple forces/factors thatare themselves insignificant could still be significant due to additive or multiplicativeinteractions. The sentence quoted above describes how the concept of “cumulative effects”is commonly implemented within current practice in the field of environmental impactassessment in Canada. The wording of this paragraph has also been modified, based onother feedback, to clarify that this perspective reflects current practice not currentstandards. The whole paragraph describes not what “cumulative effects” is or should be,but simply how it is frequently applied. But the subsequent paragraph describes why thisdefinition is inadequate and falls short of what “cumulative effects” analyses should beconsidering. We felt that contrasting very different definitions of cumulative effects wouldbe a useful way of exploring some of the important ideas underlying this complex concept.We have expanded on the point raised by the reviewer in the revised section 4.7.p. 12 / pdf 26. The approach that’s outlined for the cumulative impacts analysis (3.3.1.Overview) does not, in my opinion, fully capture the “cumulative” nature of the impactsthat are being assessed. That is, the 3 components of the approach could be examinedwithout any of the considerations that were presented earlier on how cumulativeimpacts analyses work – each could be assessed totally independently of the other, atleast the way this is written, and the way that much of the rest of the text is presented.The summary tables of exposure and likelihood of impacts of each potential stressorconsider each stressor one at a time. I don’t see anything “accumulating” here.Response: We have added discussions of potential interactions among factors to variousparts of Sections 4.2-4.6, and possible interactions across life history stages to Section 4.7.We have added some discussion in Section 2.3 to explicitly describe how the cumulativeeffects concepts described in Section 2 are integrated into the report. Point 3 in Section160
3.3.1 has been revised to say “Assess the relative likelihood of feasible explanatory factorsand their potential interactions”. We have added some discussion regarding theconsideration of cumulative effects and interactions in our methodological summary(Section 3.3.6) and Appendix 3 now provides greater discussion on some of the issues withincluding interactions in our quantitative analyses (e.g. we cannot assess the interactionswith disease because there are no data available).p. 19 / pdf 33. I like the conceptual flow diagram.Response: Thank you for the positive feedback.p. 43 / pdf 57. 4.3.2 Exposure of Fraser River sockeye to stressors. It would be good toadd a couple sentences reminding readers how the Nelitz et al. index of cumulativestress works.Response: Added to Section 4.3.2.p. 46 / pdf 60. “As discussed above, MacDonald et al. (2011) compared watercontaminant concentrations during the smolt migration period with thresholdsestablished from laboratory and field studies, and no evidence against the hypothesisthat contaminants encountered by smolts contributed to declining sockeye productivity.”I’m not sure what this means: did they find evidence against the hypothesis because oflack of information, or perhaps evidence for the hypothesisResponse: Thank you for catching this error. The phrase “against the hypothesis” shouldbe removed.p. 49-49 / pdf 62-63. It seems odd that sea lice are not mentioned in the section onpotential pathogens. They were mentioned in several places in the Disease report,though not in much detail.Response: We limited our discussion of potential pathogens to those that Kent (2011;Pathogens and Disease) evaluated as being “high risk”. Kent (2011) ranked the sea lice L.salmonis and C. clemensi as “moderate risk”. He reports that there are many researchpublications (both finding and failing to find support) on the purported link betweensalmon farms, sea lice and increases in mortality of wild pink and chum populations. Kent(2011) further reports that “there are reports of L. salmonis infections on sockeye salmon,but there is not [any] direct indication that the parasite causes significant mortality in thisspecies”. However, it is not clear whether this conclusion reflects findings based on actualdata or simply reflects an overall lack of appropriate data to test for such a relationship.When the technical reports on aquaculture are available, an addendum to this report willbe completed to assess the cumulative effects on sockeye including salmon farms.p. 53 / pdf 67. “For example, if 0.1% of the diet of spiny dogfish was sockeye smolts,they would consume 14.5 million smolts within the Strait of Georgia (very significant161
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April 2011technical report 6Fraser
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Stage 2: Smolt OutmigrationWe analy
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of multiple stressors and factors,
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4.3.5 Other evidence ..............
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List of TablesTable 4.2-1. Evaluati
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List of FiguresFigure 2.3-1. Cumula
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these integrative frameworks, conve
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2.0 Cumulative Impacts or Effects2.
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assumed that there is no potential
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classes of stressors. However, if s
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affected by many stressors over its
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examples illustrate this problem --
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possibly even negligible component
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Figure 3.3-1. The conceptual model
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3.3.3 Life history perspective/appr
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additional analyses to gain further
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Figure 3.3-3. Flow diagram used to
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This project is unusual in its scop
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4.0 Results, Synthesis and Discussi
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Peterman and Dorner (2011) have thr
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Figure 4.1-3. Estimates of long ter
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Figure 4.1-5. A) Total run size of
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Figure 4.1-6. Aggregate returns to
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o were generally worse during the l
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Freshwater predators on juvenile so
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copper, iron, mercury and silver).
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Several analyses by MacDonald et al
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abundances (Sproat, Klukshu, Chilka
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feel reasonably confident in this c
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Nelitz et al. (2011; Table 18) foun
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in the Lower Fraser than other Fras
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stressors. Thus our conclusions hav
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There are many marine predators tha
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assumption that exposure occurs whe
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observations that are then averaged
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Johannes et al. (2011) demonstrate
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“likely” contributor to the ove
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Table 4.4-2. Model specifications f
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Region Variable M1 M2 M3 M4 M5 M6 M
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3. survival rates within key portio
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2011). The thermal limit hypothesis
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Historically, the majority of retur
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salinity. There is much evidence th
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declines (discussed in section 4.2
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There is indisputable evidence of t
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Figure 4.6-2. Number of years that
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correlation was statistically signi
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4.6.7 Key things we need to know be
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al (2010). The combined effect of a
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more likely to suffer en-route and
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Table 4.7-2. Variables included in
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However, an important limitation is
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Alternative PreyVariablesModelsM1 M
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will likely have a high correlation
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5.0 Conclusion5.1 Important Contrib
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Stage 5: Migration back to SpawnWhi
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More specifically, the extended res
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The twelve highest priority recomme
Page 125 and 126: Life stagefor FraserRiversockeyesal
Page 127 and 128: 6.0 ReferencesAinsworth, L.M., Rout
Page 129 and 130: Johannes, M.R.S., R. Hoogendoorn, R
Page 131: Schaller et al. 2007. Comparative S
Page 134 and 135: utilized to clarify the full range
Page 137 and 138: Appendix 2. Reviewer Evaluations an
Page 139 and 140: the conclusions of the Expert Panel
Page 141 and 142: Response: Figure numbers have been
Page 143 and 144: Response: This section has been com
Page 145 and 146: ased on time or other stocks) to
Page 147 and 148: them in terms of how changes in spa
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Page 151 and 152: ... (Table xx)". Structures of thes
Page 153 and 154: Report Title: Fraser River sockeye
Page 155 and 156: show stronger correlations. Hence,
Page 157 and 158: Fraser and non-Fraser sockeye popul
Page 159 and 160: a single database for other researc
Page 161 and 162: Response: We have removed the itali
Page 163 and 164: evidence unique to each life stage.
Page 165 and 166: Report Title: Data Synthesis and Cu
Page 167 and 168: Response: We have further emphasize
Page 169 and 170: 5. I would also encourage the autho
Page 171 and 172: events occur, it should be possible
Page 173 and 174: I don’t have anything to add beyo
Page 175: constitutes an exposure to human ac
Page 179: most likely contributors to the rec
Page 182 and 183: A3.2.1 Integrative quantitative met
Page 184 and 185: Table A3.3-1. A summary of data set
Page 186 and 187: ProjectNumber Project Name Variable
Page 188 and 189: ProjectNumber Project Name Variable
Page 190 and 191: A3.4 Data PreparationContractor dat
Page 192 and 193: Table A3.4-2. An example entry in t
Page 194 and 195: Table A3.4-5. Brood year adjustment
Page 196 and 197: Table A3.4-7. Example output from t
Page 198 and 199: Table A3.4-9. The table of contents
Page 200 and 201: ProjectNumberProject Variable Subse
Page 212 and 213: The objective of our approach is to
Page 214 and 215: investigated ecosystems” (Burkhar
Page 216 and 217: Figure A3.5-1. Flow diagram used to
Page 218 and 219: multiple stresses simultaneously. T
Page 220 and 221: Change point analysis of productivi
Page 222 and 223: Figure A3.5-1. This is an example o
Page 224 and 225: ecruits for this analysis as we wan
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exclude covariates with limited yea
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Figure A3.5-3. Average chlorophyll
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Status only data setsIn many cases
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The A-series of model sets based on
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with this report given the vast sco
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Table A3.5-5. Example of the model
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categories of stressors. We cannot
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o In some cases it may be the timin
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Appendix 4. Quantitative ResultsA4.
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alance” over time and so this it
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Figure A4.2-3. Stock composition fo
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Figure A4.2-5. Stock composition fo
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A4.3 Multiple Regression ResultsA4.
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Life stage Stressor category Variab
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The results show strong support for
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ModelSet_A4c_VarName M1 M2 M3 M4 M5
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Table A4.3-7. Estimates for all fix
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A4.3.3Analyses by stressor category
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Table A4.3-10. Estimates for all fi
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Model: B4bBrood years: 1969-2001We
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A4.3.4Analysis by regionModel: C4a1
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suggest any underlying mechanism, b
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Model: C1a1996-2004For 1996-2004, i
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Table A4.3-23. SoG C1a candidate mo
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Appendix 5. Data Template User Guid
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Metric Connected to Biologically-su
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Initial Conceptual Model (Worksheet
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Commentsopen again. It is acceptabl
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Appendix 6. Workshop Report 1 (Nov.
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Table of ContentsTable of Contents
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PresentationsProductivity Dynamics
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and scope for improvement, particul
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Workshop participants pointed out t
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o Can you find the same shared tren
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generally better for Alaska sockeye
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Relative Likelihood of Alternative
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There was widespread agreement with
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Appendix A: List of Projects and In
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Peer Reviewers: Provide constructiv
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MacDonald Environmental Sciences Lt
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Appendix C: Workshop MinutesContent
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Levy urged researchers to bear in m
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within-population, within-brood-yea
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To address potential skepticism ove
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instead of migrating directly out i
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considered a good surrogate of temp
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Bristol Bay review: There are subst
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Method: The approach included formu
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Staley: Our project needs to compar
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Levy: It will go ahead in January.
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preliminary assessment of potential
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MacDonald: We’re waiting for all
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including Shuswap and North Thompso
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and biological variables. The combi
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temperatures. Notably, it doesn’t
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Seasonal population distribution pa
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Information gaps: The most importan
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Fraser sockeye salmon habitat analy
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survey data, but they were looking
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was also shown that tagged fish ret
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English: There was extensive holdin
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periods showed that 4 to 6 stocks (
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Q/A: Researchers should also feel f
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Peterman: We’re lacking the big p
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Appendix D: Table of likelihood/ hy
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Fraser River sockeye salmon: data synthesis and cumulative impacts

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