Fraser River sockeye salmon: data synthesis and cumulative impacts

Table 5.2-1. Recommended research and monitoring priorities listed by sockeye life stage. This table builds onPeterman et al. (2010; Table E-3), as well as the Cohen Commission workshop and technical reports(including this one). The importance of recommended research and monitoring activities is rated by: (1)“Explanatory Importance", i.e., the relative likelihood that the set of hypothesized factors listed in thesecond column for a given life stage contributed to the sockeye declines (i.e., a synthesis across thestressors affecting that life stage), and (2) “Relevance to Management Actions”, i.e., the value that suchknowledge has for informing potential management actions. For example, a rating of High for“Explanatory Importance” and Low for “Relevance to Management Actions” indicates that research andmonitoring of this life stage and the associated stressors is valuable in explaining the causes of decreasingproductivity, but has little relevance to informing choices about potential management actions. Boldfaceitems indicate the highest priority research and monitoring topics.Life stagefor FraserRiversockeyesalmonParentalspawningsuccess andincubationJuvenilerearing,productioncapacity,and smoltproductionRelevantreportsectionExplanatoryImportanceRelevancetoManagementActionsComments and recommended research and monitoringactivities4.2 Low Low Although an unlikely explanation of past declines, spawningsuccess and incubation could relate to disease concernsand/or become higher priority in the future with climatechange. Recommended activities include:1. better estimates of both watershed conditions overtime using consistent methods, for a strategicallyselected cross-section of stocks with varyingconditions (e.g., migration distance, levels and typesof watershed disturbance), to better understandcurrent status, causative mechanisms and riskthresholds;2. better understanding of the status of smallerconservation units, consistent withimplementation of the Wild Salmon Policy; and3. better integration of existing and future data setsaffecting freshwater spawning and rearing habitats4.2 Medium High Quantitative assessment of smolt production is essential toestimate survival rates in pre- and post-juvenile life stages,and focus management responses. Only 2 of 19 Fraserstocks currently have smolt estimates (Cultus, Chilko).Recommended activities include:4. assessments of freshwater smolt productionand health for a strategically selected crosssectionof stocks (as described above);5. studies of conditions and ecosystem dynamicswithin the rearing lakes for these stocks; and6. more intensive examinations if problems aredetected.Downstreammigration toestuary4.3 Medium High We do not know the survival rate of smolts during theirdownstream migration, or when they arrive in the Fraserestuary (vital to understanding potential mismatches betweenarrival times and marine plankton blooms). Smolt survivalcurrently cannot be estimated separately from the overalljuvenile-to-adult survival rate. Recommended activities108