Prior to the construction of the dams, migrating salmonid species accessed the upper reaches of the Capilano, Seymour, and Coquitlam watersheds as an integral part of their natural lifecycle. There are multiple initiatives being undertaken by BC Hydro and the stakeholders to re-introduce sockeye salmon (Oncorhynchus nerka) to one of their natural habitat in the upper Coquitlam watershed. Concerns have been raised that the restoration may be in conflict with the drinking water mandate of Metro Vancouver’s watershed management policies. The research objective of this project was to investigate and assess the social, economic, and environmental aspects of restoring an extirpated sockeye salmon population. Through an exploratory case-study approach, the research concluded that the existing fish passage constraints and reliance upon re-anadromy to restore the population are limiting factors in sustaining the Coquitlam Reservoir sockeye.

From 2006-2011, four population reintroduction techniques were applied to three sites within a reach of the upper Clinch River in Virginia designated suitable for population restoration of the federally endangered oyster mussel (Epioblasma capsaeformis). These techniques were: 1) translocation of adults (Site 1), 2) release of laboratory-propagated sub-adults (Site 1), 3) release of 8-week old laboratory-propagated juveniles (Site 2), and 4) release of stream-side infested host fishes (Site 3). Demographic data were collected in 2011 and 2012 by systematic quadrat and capture-mark-recapture sampling to assess reintroduction success, evaluate reintroduction techniques, and compare survey approaches for monitoring freshwater mussels. Estimates of abundance and density of translocated adults ranged from 450-577 individuals and 0.09-0.11/m2 in 2011, and 371-645 individuals and 0.07-0.13/m2 in 2012. Estimates of abundance and density of laboratory-propagated sub-adults ranged from 1,678-1,943 individuals and 0.33-0.38/m2 in 2011, and 1,389-1,700 individuals and 0.27-0.33/m2 in 2012. Additionally, three recruits were collected at Site 1. No E. capsaeformis were collected at Sites 2 and 3. Capture-mark-recapture sampling produced similar mean point estimates as systematic quadrat sampling, but with typically more precision. My results indicated that the release of larger individuals (>10 mm) is the most effective technique for restoring populations of E. capsaeformis, and that systematic quadrat and capture-mark-recapture sampling have useful applications in population monitoring that are dependent on project objectives. Systematic quadrat sampling is recommended when the objective is to simply estimate and detect trends in population size for species of moderate to larger densities (>0.2/m2). Capture-mark-recapture sampling should be used when objectives include assessing a reintroduced population of endangered species or at low density, obtaining precise estimates of population demographic parameters, or estimating population size for established species of low to moderate density (0.1-0.2/m2). The ability to grow endangered juveniles to larger sizes in captivity requires improving grow-out culture methods of laboratory-propagated individuals. A laboratory experiment was conducted to investigate the effects of temperature (20-28 C) on growth and survival of laboratory-propagated juveniles of the Cumberlandian combshell (Epioblasma brevidens), E. capsaeformis, and the wavyrayed lampmussel (Lampsilis fasciola) in captivity. Results indicated that 26 C is the optimum temperature to maximize growth of laboratory-propagated juveniles in small water-recirculating aquaculture systems. Growing endangered juveniles to larger sizes will improve survival in captivity and after release into the wild. As a result, hatcheries can reduce the time that juveniles spend in captivity and thus increase their overall production and enhance the likelihood of success of mussel population recovery efforts by federal and state agencies, and other partners. / Master of Science