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• 1. [Article] The distribution and aggregation of Chinook salmon stocks on the Oregon Shelf as indicated by the commercial catch and genetics

  Project CROOS, Collaborative Research on Oregon Ocean Salmon, is a unique partnership of scientists and commercial fishermen that combines catch location data with stock assignments obtained from genetic ...

  Citation × Citation Citation Abstract Copy Title: The distribution and aggregation of Chinook salmon stocks on the Oregon Shelf as indicated by the commercial catch and genetics Author: Ireland, Robert (Robert Carey) Project CROOS, Collaborative Research on Oregon Ocean Salmon, is a unique partnership of scientists and commercial fishermen that combines catch location data with stock assignments obtained from genetic micro-satellite analysis to investigate the distribution of Oregon Chinook across multiple spatial scales. Using catch data collected by collaborating Oregon troll fishermen, we investigated the distribution of individual populations of Chinook salmon along the nearshore regions of the Oregon Coast. The study focused on two distinct spatial scales: 1) the coast-wide, latitudinal distribution of the 13 most abundant stocks that contributed to the Oregon catch in 2007, and 2) stock-based patterns of Chinook aggregation on spatial scales as low as tens to hundreds of meters. The description of spatial distribution was performed over time periods as short as two days and in season-long summaries. Based on 2007 catch data, we report three separate patterns in the coastal distribution of Oregon-caught Chinook. Stocks from the Sacramento River, Mid-Oregon Coast and Upper Columbia basin were distributed coast-wide in the Oregon catch. Chinook salmon that originated from northern California and southern Oregon were found to be more abundant south of 44° North – the approximate latitude of the coastal town of Florence, Oregon. Stocks from the north Oregon coast and the lower Columbia basin were primarily taken north of 44° North. We describe in-season and annual changes in the relative contribution of discrete stocks and in the age-structure of these stocks. Using distance-based metrics compared to random permutations, we found evidence from the ocean catch that Chinook salmon were sometimes closely proximate to river cohorts at sea. However, these discreet stocks were generally intermingled with other stocks in mixed-stock aggregations. Title: The distribution and aggregation of Chinook salmon stocks on the Oregon Shelf as indicated by the commercial catch and genetics Author: Ireland, Robert (Robert Carey) Project CROOS, Collaborative Research on Oregon Ocean Salmon, is a unique partnership of scientists and commercial fishermen that combines catch location data with stock assignments obtained from genetic micro-satellite analysis to investigate the distribution of Oregon Chinook across multiple spatial scales. Using catch data collected by collaborating Oregon troll fishermen, we investigated the distribution of individual populations of Chinook salmon along the nearshore regions of the Oregon Coast. The study focused on two distinct spatial scales: 1) the coast-wide, latitudinal distribution of the 13 most abundant stocks that contributed to the Oregon catch in 2007, and 2) stock-based patterns of Chinook aggregation on spatial scales as low as tens to hundreds of meters. The description of spatial distribution was performed over time periods as short as two days and in season-long summaries. Based on 2007 catch data, we report three separate patterns in the coastal distribution of Oregon-caught Chinook. Stocks from the Sacramento River, Mid-Oregon Coast and Upper Columbia basin were distributed coast-wide in the Oregon catch. Chinook salmon that originated from northern California and southern Oregon were found to be more abundant south of 44° North – the approximate latitude of the coastal town of Florence, Oregon. Stocks from the north Oregon coast and the lower Columbia basin were primarily taken north of 44° North. We describe in-season and annual changes in the relative contribution of discrete stocks and in the age-structure of these stocks. Using distance-based metrics compared to random permutations, we found evidence from the ocean catch that Chinook salmon were sometimes closely proximate to river cohorts at sea. However, these discreet stocks were generally intermingled with other stocks in mixed-stock aggregations. Close

• 2. [Article] Variation in smolt quality of juevnile spring Chinook Salmon

  As juvenile salmon migrate from freshwater into saltwater, physiological changes must occur to allow fish to osmoregulate in the marine environment. Juvenile spring Chinook salmon migrate to the ocean ...

  Citation × Citation Citation Abstract Copy Title: Variation in smolt quality of juevnile spring Chinook Salmon Author: Danley, C., Noakes, D. L. G., Billman, E. J., Palmer, Rachel M., Sharpe, C. As juvenile salmon migrate from freshwater into saltwater, physiological changes must occur to allow fish to osmoregulate in the marine environment. Juvenile spring Chinook salmon migrate to the ocean at different time periods, most notably in the fall (August – November; i.e. fall smolts) and spring (February – May; i.e. spring smolts) after their first summer of rearing. We tested the ability of laboratory reared fall and spring smolts to osmoregulate when placed in salt water from freshwater by comparing differences in plasma sodium concentration after a 24-hr salt water challenge. The fish were reared under two different regimes in which we manipulated temperature and feed in order to produce different growth rates such that fall smolts exhibited a faster growth rate. We conducted four salt water challenges from 28 August – 11 December (approximately once per month). Interestingly, spring fish when tested in the fall still were able to be saltwater tolerant. All fish survived the salt water challenges. Fall smolts had significantly lower plasma sodium concentrations in the first two challenges, indicating a higher smolt quality. However, plasma sodium concentrations in fall smolts increased each month, suggesting they were reverting in smolt quality. Spring smolts had mean plasma sodium concentrations below the 170 mM/L threshold which has been suggestive smoltification. However, spring smolts had greater variation in plasma sodium concentrations with approximately 65% of the fish having levels below the smoltification threshold, compared to > 85% in fall smolts. The ability of fall and spring smolts to regulate plasma sodium during salt water challenges indicated both groups could survive in the ocean, suggesting that fall and spring smolts would migrate if there was a match between physiological and environmental factors. Title: Variation in smolt quality of juevnile spring Chinook Salmon Author: Danley, C., Noakes, D. L. G., Billman, E. J., Palmer, Rachel M., Sharpe, C. As juvenile salmon migrate from freshwater into saltwater, physiological changes must occur to allow fish to osmoregulate in the marine environment. Juvenile spring Chinook salmon migrate to the ocean at different time periods, most notably in the fall (August – November; i.e. fall smolts) and spring (February – May; i.e. spring smolts) after their first summer of rearing. We tested the ability of laboratory reared fall and spring smolts to osmoregulate when placed in salt water from freshwater by comparing differences in plasma sodium concentration after a 24-hr salt water challenge. The fish were reared under two different regimes in which we manipulated temperature and feed in order to produce different growth rates such that fall smolts exhibited a faster growth rate. We conducted four salt water challenges from 28 August – 11 December (approximately once per month). Interestingly, spring fish when tested in the fall still were able to be saltwater tolerant. All fish survived the salt water challenges. Fall smolts had significantly lower plasma sodium concentrations in the first two challenges, indicating a higher smolt quality. However, plasma sodium concentrations in fall smolts increased each month, suggesting they were reverting in smolt quality. Spring smolts had mean plasma sodium concentrations below the 170 mM/L threshold which has been suggestive smoltification. However, spring smolts had greater variation in plasma sodium concentrations with approximately 65% of the fish having levels below the smoltification threshold, compared to > 85% in fall smolts. The ability of fall and spring smolts to regulate plasma sodium during salt water challenges indicated both groups could survive in the ocean, suggesting that fall and spring smolts would migrate if there was a match between physiological and environmental factors. Close

• 3. [Article] AFS_Poster_Final.pptx

  Citation × Citation Citation Abstract Copy Title: AFS_Poster_Final.pptx Author: Danley, C., Noakes, D. L. G., Billman, E. J., Palmer, Rachel M., Sharpe, C. Title: AFS_Poster_Final.pptx Author: Danley, C., Noakes, D. L. G., Billman, E. J., Palmer, Rachel M., Sharpe, C. Close

• 4. [Article] PalmerRachelM2015.pdf

  Citation × Citation Citation Abstract Copy Title: PalmerRachelM2015.pdf Author: Danley, C., Sharpe, C., Billman, E. J., Palmer, Rachel M., Noakes, D. L. G. Title: PalmerRachelM2015.pdf Author: Danley, C., Sharpe, C., Billman, E. J., Palmer, Rachel M., Noakes, D. L. G. Close