Lake Babine Nation Fisheries (LBNF) plans to work with Fisheries and Oceans Canada (DFO) to continue the investigation of the behaviour and ecology of Babine River sockeye fry. The proposed project is composed of four relatively discrete components which include:
- early life history behaviour and migration;
- extent and rate of predation on juvenile sockeye;
- egg-to-fry and fry-to-smolt survival, frequency of occurrence of disease and parasites and condition as a function of length and weight; and
- presence and behaviour of sockeye fry rearing in downstream slow water habitats to obtain evidence of a riverine juvenile sockeye ecotype.
Other observed adverse effects that may affect sockeye fry survival and overall sockeye production will be documented. These studies are intended to address the diminished abundance of Late Run Upper and Lower Babine River sockeye in their juvenile freshwater environment.
While Fraser River sockeye salmon survival has declined over the past decade, it has also exhibited high interannual variability. The processes responsible for this trend and the variability are not understood and require investigation. This project builds on the previous work by adding a fifth year of sampling juvenile migrants immediately prior to their entry into the Strait of Georgia (SoG). The sampling platform will be identical to that employed successfully in 2013-2015, and GSI analysis will help to provide estimates of relative abundance and migration timing past Mission by stock. It is anticipated that sampling intensity in 2016, a juvenile Pink Salmon outmigration year, will be similar to that in 2014. In 2016, we propose to repeat the 2014 & 2015 study design and parameters assessed, including the assessment of the nocturnal migration patterns of Sockeye juveniles for a third year.
As in previous years, samples collected under this project will be compared to samples collected in other ongoing and proposed assessments, such as DFO’s annual SoG trawl survey occurring June-July and a similar trawl survey in Johnstone Strait. In combination, these three studies will add a third year to a comprehensive multi-stock assessment of Fraser River juvenile sockeye salmon relative abundance and condition, from nursery lake exit through early marine near-shore residency.
Sub-yearling ocean-migrant sockeye salmon (e.g. Harrison River stock) can be important contributors to Fraser River Sockeye production. The 2016 survey will continue to incorporate the bio-sampling of captured sub-yearling juveniles to identify their contribution, and migration timing at Mission by Conservation Unit (CU).
Lastly, the 2016 project will explore the feasibility of deploying an acoustic Doppler current profiler in an attempt to measure water current velocities over a depth range. This information may be important in determining absolute juvenile sockeye abundance at Mission.
The primary objective of this trans-generational genetic mark-recapture (tGMR) project is to: 1) estimate the abundance of Chinook salmon spawners and effective breeders in the Stillaguamish River above the smolt trap site using genetic abundance methods. The secondary objectives of this study are to: 2) estimate the natural spawning Chinook salmon abundance by origin (hatchery or natural), sex and age, and 3) estimate a redd expansion calibration factor from historic redd-based escapement estimates and possible future redd counts. The data collected for this project also provide a genetic baseline for these population estimates, a genetic (parentage-based) estimate of the proportion of hatchery-origin spawners, and an estimate of relative reproductive success of hatchery spawners, because carcasses are classified by origin. Genetic sampling will be conducted during the fall spawning period, and smolt trapping will be conducted during the following spring.
The Lake Babine Nation Fisheries Department (LBNF), in collaboration with the DFO, propose to build on success in the smolt project by continuing to operate the Babine smolt enumeration facilities to provide sockeye smolt emigration estimates and smolt fitness data for the Babine Lake Watershed. Smolt production and fitness are effective indicators of Babine Lake ecosystem health which can be used to initiate and direct resource management initiatives intended to protect the Babine Lake watershed. We believe that continuous data from the Babine smolt enumeration fence would provide important information on Babine sockeye population status that will contribute critical information to the understanding the large inter-annual variations in returns observed in the past two decades. An uninterrupted set of sockeye smolt population data over multiple years will help address one of the most fundamental questions of salmon stocks management — under which conditions are freshwater or marine environments the primary driver determining salmon returns?