Fraser River sockeye salmon: data synthesis and cumulative impacts

Key issues raised by workshop participants included: 1) the availability of other salmon speciesas alternate prey to predators; 2) a very small percentage of predator diet consisting of sockeye isnot enough to reject a potential predator as influential, without more data such as DNA or bioenergeticanalyses; and 3) it is important to examine the overlap of predators and smolts in bothspace and time.Fraser Sockeye Salmon Habitat Analysis: Lower Fraser River & Straitof GeorgiaMark Johannes, Golder AssociatesThe objectives of this study are to identify and evaluate key sockeye habitats and habitat use inthe Lower Fraser, Fraser Estuary and Strait of Georgia. Key indicators include anthropogenicchanges and biophysical characteristics in the Strait of Georgia, focusing on the period from1990 to 2010. Researchers used spatial and temporal overlays of the indicators with thedegradation of key sockeye habitat to determine potential interactions. Comparisons to the PSCreport were preliminary, but so far showed agreement (Peterman et al. 2010). A major data gap isthe lack of clear indicators on human development. Consistent indicators of biophysicalconditions in Strait of Georgia and biological observations of sockeye habitat use are alsolimited. There is a general lack of time series data.A key issue raised by workshop participants is the broad scope of the research topic. Onesuggestion was to focus on locations and times that sockeye are in specific areas. Othersuggestions included consideration of river discharge (temperature effects), light pollution inGeorgia Strait, and the relative importance of Lower Fraser habitats versus larger scale factors.Climate & Climate Change Effects on Fraser SockeyeScott Hinch, UBCEduardo Martins, UBCThe overarching theme of this research is to review the occurrence and effects of climate changeon Fraser River sockeye and their relative importance to their long-term decline. The first part ofthis study examined en route mortality, pre-spawn mortality and intergenerational effects. Thesecond study component assessed the relationships between climate and climate-affectedvariables (temperature, precipitation, river flow, salinity) and sockeye salmon survival andproductivity. Hinch showed that en route loss can be large relative to harvest and spawningescapement, and has become really important in recent years; nine out of 12 stocks had highmortality in more than 50% of recent years. Contrast among non-Fraser stocks showed theopposite effects of temperatures between southern and northern stocks (e.g, warmer years are