Monster Seminar Jam - Quantifying mixing and migration in Pacific salmon: implications for conservation and management
Dr. Jessica Miller, Fisheries and Wildlife, Oregon State University
Salmon are an integral and diverse component of Pacific Northwest ecosystems and display broad arrays of naturally-occurring variation in numerous life history traits, e.g., size- and age-at-reproduction, smolt age, and fecundity. Life history theory predicts that variation in certain traits imparts persistence and resilience to a species and its local populations. Certain traits, such as juvenile and adult migratory behavior, also display large amounts of variation and some behaviors appear to have a genetic basis but their effects on fitness are not well understood. Although detailed description of natural variation and its relevance to persistence and resilience of salmon populations are important components of successful management and conservation, there are numerous life history aspects that are poorly understood. The successful management of Pacific salmon relies, in part, on understanding migratory behavior and determining how variation in migratory behavior affects growth and survival. Aspects of current research focus on quantifying migratory behavior and mixing using the chemical signatures of otoliths, which are the calcium carbonate ear bones of teleost fishes. Recent research efforts include an estimate of the mixed stock composition of Chinook salmon (Oncorhynchus tshawytscha) within a terminal fishery in southern Oregon using otolith isotopic (87Sr/86Sr) and microsatellite genetic analyses, reconstruction of individual migratory and growth histories of ocean-caught juvenile steelhead (O. mykiss) using otolith Sr/Ca concentrations, and efforts to reconstruct migratory histories of mid- and upper-Columbia Chinook salmon.
Date and Time:
January 24, 2008,
11:00 am - 12:30 pm