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• 1. [Article] Length and age at maturity of female yelloweye rockfish (Sebastes rubberimus) and cabezon (Scorpaenichthys marmoratus) from Oregon waters based on histological evaluation of maturity Information Report number 2009-04

  Abstract -- Accurate estimates of female age or length at maturity are critical for the conservation of exploited fish stocks. Age at maturity is particularly important, as it strongly influences population ...

  Citation × Citation Citation Abstract Copy Title: Length and age at maturity of female yelloweye rockfish (Sebastes rubberimus) and cabezon (Scorpaenichthys marmoratus) from Oregon waters based on histological evaluation of maturity Information Report number 2009-04 Abstract -- Accurate estimates of female age or length at maturity are critical for the conservation of exploited fish stocks. Age at maturity is particularly important, as it strongly influences population model estimates of sustainable harvest rates (Clark 1991) and, along with mean body size, is an important predictor of the risk of overexploitation (Reynolds et al. 2005). For many U.S. west coast groundfish stocks, data on age and length at maturity is of poor quality. The age at maturity curves used in many stock assessments are currently based on macroscopic (visual) assessment of ovary condition. However, there is abundant evidence that histological evaluation of ovarian thin-sections, especially if combined with optimal seasonal sampling, is much more accurate (Gunderson et al. 1980, Wyllie Echeverria 1987, West 1990, Nichol and Pikitch 1994, Hannah and Parker 2007). The age data that have been used to develop curves of age at maturity for some species is also based on outdated ageing methods, such as surface aging of otoliths, as opposed to the more accurate “break and burn” technique (Barss 1989, Wyllie Echeverria 1987, Chilton and Beamish 1982). For other species, such as cabezon (Scorpaenichthys marmoratus), accurate age and growth data, based on thin-sectioning of otoliths, have just recently been developed (Grebel and Cailliet 2003). Information on age and length at maturity that is based on histological evaluation of maturity status and modern ageing techniques is therefore needed for many U.S. west coast groundfish species. Histology-based maturity data has been developed for some U.S. west coast groundfish species. These include darkblotched rockfish (Sebastes crameri, Nichol and Pikitch 1994), petrale sole (Eopsetta jordani, Hannah et al. 2002), greenstriped rockfish (Sebastes elongatus, Shaw and Gunderson 2006), Pacific ocean perch (Sebastes alutus, Hannah and Parker 2007) and rosethorn rockfish (Sebastes helvomaculatus, Shaw and Gunderson 2008). We report here on the development of similar data for female yelloweye rockfish (Sebastes rubberimus) and cabezon. Title: Length and age at maturity of female yelloweye rockfish (Sebastes rubberimus) and cabezon (Scorpaenichthys marmoratus) from Oregon waters based on histological evaluation of maturity Information Report number 2009-04 Abstract -- Accurate estimates of female age or length at maturity are critical for the conservation of exploited fish stocks. Age at maturity is particularly important, as it strongly influences population model estimates of sustainable harvest rates (Clark 1991) and, along with mean body size, is an important predictor of the risk of overexploitation (Reynolds et al. 2005). For many U.S. west coast groundfish stocks, data on age and length at maturity is of poor quality. The age at maturity curves used in many stock assessments are currently based on macroscopic (visual) assessment of ovary condition. However, there is abundant evidence that histological evaluation of ovarian thin-sections, especially if combined with optimal seasonal sampling, is much more accurate (Gunderson et al. 1980, Wyllie Echeverria 1987, West 1990, Nichol and Pikitch 1994, Hannah and Parker 2007). The age data that have been used to develop curves of age at maturity for some species is also based on outdated ageing methods, such as surface aging of otoliths, as opposed to the more accurate “break and burn” technique (Barss 1989, Wyllie Echeverria 1987, Chilton and Beamish 1982). For other species, such as cabezon (Scorpaenichthys marmoratus), accurate age and growth data, based on thin-sectioning of otoliths, have just recently been developed (Grebel and Cailliet 2003). Information on age and length at maturity that is based on histological evaluation of maturity status and modern ageing techniques is therefore needed for many U.S. west coast groundfish species. Histology-based maturity data has been developed for some U.S. west coast groundfish species. These include darkblotched rockfish (Sebastes crameri, Nichol and Pikitch 1994), petrale sole (Eopsetta jordani, Hannah et al. 2002), greenstriped rockfish (Sebastes elongatus, Shaw and Gunderson 2006), Pacific ocean perch (Sebastes alutus, Hannah and Parker 2007) and rosethorn rockfish (Sebastes helvomaculatus, Shaw and Gunderson 2008). We report here on the development of similar data for female yelloweye rockfish (Sebastes rubberimus) and cabezon. Close

• 2. [Article] Nilestun Year 2 Efficacy Monitoring Report - Juvenile Fish Response

  Abstract -- Catch per unit effort data were gathered for three salt marsh restoration sub-basins, three mainstem river reference locations, and a salt marsh reference sub-basin. Report results cover May-Aug ...

  Citation × Citation Citation Abstract Copy Title: Nilestun Year 2 Efficacy Monitoring Report - Juvenile Fish Response Abstract -- Catch per unit effort data were gathered for three salt marsh restoration sub-basins, three mainstem river reference locations, and a salt marsh reference sub-basin. Report results cover May-Aug occupancy and catch per unit effort during the second year after restoration. Results suggest significant response by age-0 and age-1 salmonids. More broad results provided in the report cover tidal inundation, exchange rates, salinity, temperature, soil moisture and plant communities. Title: Nilestun Year 2 Efficacy Monitoring Report - Juvenile Fish Response Abstract -- Catch per unit effort data were gathered for three salt marsh restoration sub-basins, three mainstem river reference locations, and a salt marsh reference sub-basin. Report results cover May-Aug occupancy and catch per unit effort during the second year after restoration. Results suggest significant response by age-0 and age-1 salmonids. More broad results provided in the report cover tidal inundation, exchange rates, salinity, temperature, soil moisture and plant communities. Close

• 3. [Article] Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin; Annual Report 2009

  Abstract -- In 2009, 3,745 natural and 28,880 hatchery smolts were collected in the juvenile bypass facility at Three Mile Falls Dam (TMFD). A total of 2,876 PIT tagged juvenile salmon and steelhead and ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin; Annual Report 2009 Abstract -- In 2009, 3,745 natural and 28,880 hatchery smolts were collected in the juvenile bypass facility at Three Mile Falls Dam (TMFD). A total of 2,876 PIT tagged juvenile salmon and steelhead and 104 adults were detected. Mean fork length at emigration for natural summer steelhead was 168 mm. Age at emigration was 29.9% age-1 and 70.1% age-2. Condition factor for steelhead smolts was poor (< 1.00) throughout the season and Neascus sp. (black spot), continued to be prevalent. Median emigration time to TMFD and John Day Dam (JDD) for natural summer steelhead occurred in the middle of May (5/14-5/20) compared to late May (5/21-5/27) at Bonneville Dam (BON) and early June (5/28-6/3) at the Columbia River Estuary. Abundance for natural origin summer steelhead was 33,883 ± 4,262 smolts. Survival from Meacham Creek to TMFD, TMFD to JDD, and JDD to BON for the 2009 outmigration year was 47%, 60%, and 38%; respectively. For brood year 2007, we estimated the production of 16 smolts-per-female for summer steelhead. Egg-to-smolt survival for summer steelhead in brood year 2007 was 0.3% and smolt-to-adult return for outmigration year 2007 was 5.4%. The number of spawning females and egg deposition appeared to be associated with the growth, age composition, and production of summer steelhead smolts, thus providing evidence for density dependent effects. Growth appeared to be better during the first rearing season when fish densities were low, leading to a higher composition of age-1 smolts and more smolts produced per spawning female. The downward trend observed in egg-to-smolt survival and correlation between summer low flows and egg-to-smolt survival suggest that smolt production and freshwater productivity of summer steelhead is limited by the quantity and quality of available freshwater habitat. Title: Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin; Annual Report 2009 Abstract -- In 2009, 3,745 natural and 28,880 hatchery smolts were collected in the juvenile bypass facility at Three Mile Falls Dam (TMFD). A total of 2,876 PIT tagged juvenile salmon and steelhead and 104 adults were detected. Mean fork length at emigration for natural summer steelhead was 168 mm. Age at emigration was 29.9% age-1 and 70.1% age-2. Condition factor for steelhead smolts was poor (< 1.00) throughout the season and Neascus sp. (black spot), continued to be prevalent. Median emigration time to TMFD and John Day Dam (JDD) for natural summer steelhead occurred in the middle of May (5/14-5/20) compared to late May (5/21-5/27) at Bonneville Dam (BON) and early June (5/28-6/3) at the Columbia River Estuary. Abundance for natural origin summer steelhead was 33,883 ± 4,262 smolts. Survival from Meacham Creek to TMFD, TMFD to JDD, and JDD to BON for the 2009 outmigration year was 47%, 60%, and 38%; respectively. For brood year 2007, we estimated the production of 16 smolts-per-female for summer steelhead. Egg-to-smolt survival for summer steelhead in brood year 2007 was 0.3% and smolt-to-adult return for outmigration year 2007 was 5.4%. The number of spawning females and egg deposition appeared to be associated with the growth, age composition, and production of summer steelhead smolts, thus providing evidence for density dependent effects. Growth appeared to be better during the first rearing season when fish densities were low, leading to a higher composition of age-1 smolts and more smolts produced per spawning female. The downward trend observed in egg-to-smolt survival and correlation between summer low flows and egg-to-smolt survival suggest that smolt production and freshwater productivity of summer steelhead is limited by the quantity and quality of available freshwater habitat. Close

• 4. [Article] Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Report 2000

  Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, ...

  Citation × Citation Citation Abstract Copy Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Report 2000 Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context for project-specific effectiveness monitoring efforts. To meet the data needs as index stocks, to assess the long-term effectiveness of habitat projects, and to differentiate freshwater and ocean survival, sufficient annual estimates of spawner escapement, age structure, SAR, egg-to-smolt survival, smolt-per-redd ratio, and freshwater habitat use are essential. We have begun to meet this need through spawning ground surveys initiated for spring Chinook salmon in 1998 and smolt PIT-tagging efforts initiated in 1999. Additional sampling and analyses to meet these goals include an estimate of smolt abundance and SAR rates, and an updated measure of the freshwater distribution of critical life stages. ODFW, Eastern Oregon Fish Research (EOFR) Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Report 2000 Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context for project-specific effectiveness monitoring efforts. To meet the data needs as index stocks, to assess the long-term effectiveness of habitat projects, and to differentiate freshwater and ocean survival, sufficient annual estimates of spawner escapement, age structure, SAR, egg-to-smolt survival, smolt-per-redd ratio, and freshwater habitat use are essential. We have begun to meet this need through spawning ground surveys initiated for spring Chinook salmon in 1998 and smolt PIT-tagging efforts initiated in 1999. Additional sampling and analyses to meet these goals include an estimate of smolt abundance and SAR rates, and an updated measure of the freshwater distribution of critical life stages. ODFW, Eastern Oregon Fish Research (EOFR) Close

• 5. [Article] Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 2001

  Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, ...

  Citation × Citation Citation Abstract Copy Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 2001 Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context for project-specific effectiveness monitoring efforts. To meet the data needs as index stocks, to assess the long-term effectiveness of habitat projects, and to differentiate freshwater and ocean survival, sufficient annual estimates of spawner escapement, age structure, SAR, egg-to-smolt survival, smolt-per-redd ratio, and freshwater habitat use are essential. We have begun to meet this need through spawning ground surveys initiated for spring Chinook salmon in 1998 and smolt PIT-tagging efforts initiated in 1999. Additional sampling and analyses to meet these goals include an estimate of smolt abundance and SAR rates, and an updated measure of the freshwater distribution of critical life stages. ODFW, Eastern Oregon Fish Research (EOFR) Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 2001 Abstract -- The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context for project-specific effectiveness monitoring efforts. To meet the data needs as index stocks, to assess the long-term effectiveness of habitat projects, and to differentiate freshwater and ocean survival, sufficient annual estimates of spawner escapement, age structure, SAR, egg-to-smolt survival, smolt-per-redd ratio, and freshwater habitat use are essential. We have begun to meet this need through spawning ground surveys initiated for spring Chinook salmon in 1998 and smolt PIT-tagging efforts initiated in 1999. Additional sampling and analyses to meet these goals include an estimate of smolt abundance and SAR rates, and an updated measure of the freshwater distribution of critical life stages. ODFW, Eastern Oregon Fish Research (EOFR) Close

• 6. [Article] LCMP - Residence Time and Seasonal Movements of Juvenile Coho Salmon in the Ecotone and Lower Estuary of Winchester Creek, South Slough, Oregon

  Abstract -- The juvenile life history of coho salmon Oncorhynchus kisutch in the stream-estuary ecotone of Winchester Creek, South Slough, Oregon, was investigated in 1999–2001. Seines and a rotary screw ...

  Citation × Citation Citation Abstract Copy Title: LCMP - Residence Time and Seasonal Movements of Juvenile Coho Salmon in the Ecotone and Lower Estuary of Winchester Creek, South Slough, Oregon Abstract -- The juvenile life history of coho salmon Oncorhynchus kisutch in the stream-estuary ecotone of Winchester Creek, South Slough, Oregon, was investigated in 1999–2001. Seines and a rotary screw trap were used to capture fish for dye-marking, and residence time within the ecotone was determined for recaptured marked fish. In the lower estuary, ultrasonic transmitters were used to document residence time and patterns of movement for smolts migrating to the ocean. Nearly half of each brood year moved to the estuary as subyearlings. A portion of age-0 juveniles that moved downstream during spring lived in the ecotone through summer for up to 8 months, then most moved back upstream to overwinter. Fish that moved to the ecotone during fall and winter had mean minimum residence times of 48 d in 1999 and 64 d in 2000. Some of the fish that moved to the ecotone during fall and winter moved into an off-channel beaver pond and resided there for a mean of 49 d. Spring age-1 smolts had a mean minimum residence time in the ecotone of 18 d for both years and used recently restored salt marshes and other off-channel habitats. Smolts implanted with ultrasonic transmitters lived in the lower estuary for an average of 5.8 d, during which their direction of movement corresponded to the direction of tidal flow. Title: LCMP - Residence Time and Seasonal Movements of Juvenile Coho Salmon in the Ecotone and Lower Estuary of Winchester Creek, South Slough, Oregon Abstract -- The juvenile life history of coho salmon Oncorhynchus kisutch in the stream-estuary ecotone of Winchester Creek, South Slough, Oregon, was investigated in 1999–2001. Seines and a rotary screw trap were used to capture fish for dye-marking, and residence time within the ecotone was determined for recaptured marked fish. In the lower estuary, ultrasonic transmitters were used to document residence time and patterns of movement for smolts migrating to the ocean. Nearly half of each brood year moved to the estuary as subyearlings. A portion of age-0 juveniles that moved downstream during spring lived in the ecotone through summer for up to 8 months, then most moved back upstream to overwinter. Fish that moved to the ecotone during fall and winter had mean minimum residence times of 48 d in 1999 and 64 d in 2000. Some of the fish that moved to the ecotone during fall and winter moved into an off-channel beaver pond and resided there for a mean of 49 d. Spring age-1 smolts had a mean minimum residence time in the ecotone of 18 d for both years and used recently restored salt marshes and other off-channel habitats. Smolts implanted with ultrasonic transmitters lived in the lower estuary for an average of 5.8 d, during which their direction of movement corresponded to the direction of tidal flow. Close

• 7. [Article] LCMP - Juvenile Salmonid Outmigration in the Little North Fork Wilson and Little South Fork Kilchis Rivers - 2001

  Abstract -- Since 1998, as part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) has monitored downstream migration of juvenile salmonids (Oncorhynchus spp.) ...

  Citation × Citation Citation Abstract Copy Title: LCMP - Juvenile Salmonid Outmigration in the Little North Fork Wilson and Little South Fork Kilchis Rivers - 2001 Abstract -- Since 1998, as part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) has monitored downstream migration of juvenile salmonids (Oncorhynchus spp.) in various streams along the coast. The goals of this program were discussed by Dalton (1998). Briefly, we examine migration timing and abundance of the various species by size and/or age class. In the Tillamook Bay watershed, the Tillamook County Performance Partnership (TCCP) and the Oregon Department of Forestry (ODFW) have provided funding for monitoring in the Little North Fork (LNF) Wilson and Little South Fork (LSF) Kilchis rivers. Data collected during the 2001 trapping season and an annual report are presented for juvenile salmonid out-migrant trapping on the LNF Wilson and LSF Kilchis rivers. Juvenile chinook salmon numbers had decreased greatly each year from 1998 to 2000 in both rivers, but in 2001 this trend was reversed. Data is presented as tables and figures within the report. Title: LCMP - Juvenile Salmonid Outmigration in the Little North Fork Wilson and Little South Fork Kilchis Rivers - 2001 Abstract -- Since 1998, as part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) has monitored downstream migration of juvenile salmonids (Oncorhynchus spp.) in various streams along the coast. The goals of this program were discussed by Dalton (1998). Briefly, we examine migration timing and abundance of the various species by size and/or age class. In the Tillamook Bay watershed, the Tillamook County Performance Partnership (TCCP) and the Oregon Department of Forestry (ODFW) have provided funding for monitoring in the Little North Fork (LNF) Wilson and Little South Fork (LSF) Kilchis rivers. Data collected during the 2001 trapping season and an annual report are presented for juvenile salmonid out-migrant trapping on the LNF Wilson and LSF Kilchis rivers. Juvenile chinook salmon numbers had decreased greatly each year from 1998 to 2000 in both rivers, but in 2001 this trend was reversed. Data is presented as tables and figures within the report. Close

• 8. [Article] Information Report Number 2006-02; Analysis of Factors Potentially Inflating the Marine Survival Estimate of Coho Salmon (Oncorhynchus kisutch) at Mill Creek, Yaquina River, Central Oregon Coast

  Abstract -- Scale and otolith analyses were used to determine if high marine survival estimates observed for coho salmon at an Oregon Department of Fish and Wildlife Life Cycle Monitoring Project site ...

  Citation × Citation Citation Abstract Copy Title: Information Report Number 2006-02; Analysis of Factors Potentially Inflating the Marine Survival Estimate of Coho Salmon (Oncorhynchus kisutch) at Mill Creek, Yaquina River, Central Oregon Coast Abstract -- Scale and otolith analyses were used to determine if high marine survival estimates observed for coho salmon at an Oregon Department of Fish and Wildlife Life Cycle Monitoring Project site are inflated by 1) adult coho that reared as juveniles in other tributaries straying to the site, or 2) coho dispersing out of the site as fry, rearing in nearby salt marsh habitat, then returning to the site to contribute to the adult population. Scale analysis indicated that adult straying from other tributaries in the basin was unlikely to be contributing to the high marine survival estimate at the site. Scale analysis also indicated no evidence that coho fry rearing in nearby salt marshes were smolting as age-0+ fish and returning to contribute to the adult spawner population. Analyses of otolith strontium profiles were unable to distinguish differences in habitat use for fish reared in freshwater and marsh habitat because of aberrantly high ambient strontium to calcium abundance in the freshwater environment. Therefore the method was unsuitable for determining if coho fry rearing in nearby salt marshes were smolting as age-1+ fish and returning to contribute to the adult spawner population. Title: Information Report Number 2006-02; Analysis of Factors Potentially Inflating the Marine Survival Estimate of Coho Salmon (Oncorhynchus kisutch) at Mill Creek, Yaquina River, Central Oregon Coast Abstract -- Scale and otolith analyses were used to determine if high marine survival estimates observed for coho salmon at an Oregon Department of Fish and Wildlife Life Cycle Monitoring Project site are inflated by 1) adult coho that reared as juveniles in other tributaries straying to the site, or 2) coho dispersing out of the site as fry, rearing in nearby salt marsh habitat, then returning to the site to contribute to the adult population. Scale analysis indicated that adult straying from other tributaries in the basin was unlikely to be contributing to the high marine survival estimate at the site. Scale analysis also indicated no evidence that coho fry rearing in nearby salt marshes were smolting as age-0+ fish and returning to contribute to the adult spawner population. Analyses of otolith strontium profiles were unable to distinguish differences in habitat use for fish reared in freshwater and marsh habitat because of aberrantly high ambient strontium to calcium abundance in the freshwater environment. Therefore the method was unsuitable for determining if coho fry rearing in nearby salt marshes were smolting as age-1+ fish and returning to contribute to the adult spawner population. Close

• 9. [Article] Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 1998

  Abstract -- This project provides information as directed under two measures of the Columbia Basin Fish and Wildlife Program (NPPC 1994). Measure 4.3C specifies that the key indicator populations should ...

  Citation × Citation Citation Abstract Copy Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 1998 Abstract -- This project provides information as directed under two measures of the Columbia Basin Fish and Wildlife Program (NPPC 1994). Measure 4.3C specifies that the key indicator populations should be monitored to provide detailed stock status information. In addition, measure 7.1C identifies the need for collection of population status, life history, and other data on wild and naturally spawning populations. This project was developed in direct response to recommendations and needs of the PATH project, the Fish and Wildlife Program, and the Columbia Basin Fish and Wildlife Authority Multi-Year Implementation Plan. ODFW, Eastern Oregon Fish Research (EOFR) Title: Fish Research Project Oregon; John Day Basin Spring Chinook Salmon Escapement and Productivity Monitoring - Annual Progress Report 1998 Abstract -- This project provides information as directed under two measures of the Columbia Basin Fish and Wildlife Program (NPPC 1994). Measure 4.3C specifies that the key indicator populations should be monitored to provide detailed stock status information. In addition, measure 7.1C identifies the need for collection of population status, life history, and other data on wild and naturally spawning populations. This project was developed in direct response to recommendations and needs of the PATH project, the Fish and Wildlife Program, and the Columbia Basin Fish and Wildlife Authority Multi-Year Implementation Plan. ODFW, Eastern Oregon Fish Research (EOFR) Close

• 10. [Article] Maturity of female quillback (Sebastes maliger) and china rockfish (S. nebulosus) from Oregon waters based on histological evaluation of ovaries Information Reports number 2011-01

  Abstract -- Since 2000, ODFW’s Marine Resources Program has been collecting female maturity data on a variety of groundfish species in an effort to improve the maturity data available for use in stock ...

  Citation × Citation Citation Abstract Copy Title: Maturity of female quillback (Sebastes maliger) and china rockfish (S. nebulosus) from Oregon waters based on histological evaluation of ovaries Information Reports number 2011-01 Abstract -- Since 2000, ODFW’s Marine Resources Program has been collecting female maturity data on a variety of groundfish species in an effort to improve the maturity data available for use in stock assessments (e.g. Hannah et al. 2002, Hannah and Parker 2007). For many U.S. west coast groundfish stocks, data on female age and length at maturity is of questionable quality. The maturity curves currently used in some stock assessments are based on macroscopic (visual) assessment of ovary condition. However, there is strong evidence that histological evaluation of ovarian thin-sections, especially if combined with optimal seasonal sampling, is much more accurate (Gunderson et al. 1980, Wyllie Echeverria 1987, West 1990, Nichol and Pikitch 1994, Hannah and Parker 2007). We report here on the development of histologically-based length and age at maturity data for female quillback rockfish (Sebastes maliger) and length at maturity data for female china rockfish (S. nebulosus). Title: Maturity of female quillback (Sebastes maliger) and china rockfish (S. nebulosus) from Oregon waters based on histological evaluation of ovaries Information Reports number 2011-01 Abstract -- Since 2000, ODFW’s Marine Resources Program has been collecting female maturity data on a variety of groundfish species in an effort to improve the maturity data available for use in stock assessments (e.g. Hannah et al. 2002, Hannah and Parker 2007). For many U.S. west coast groundfish stocks, data on female age and length at maturity is of questionable quality. The maturity curves currently used in some stock assessments are based on macroscopic (visual) assessment of ovary condition. However, there is strong evidence that histological evaluation of ovarian thin-sections, especially if combined with optimal seasonal sampling, is much more accurate (Gunderson et al. 1980, Wyllie Echeverria 1987, West 1990, Nichol and Pikitch 1994, Hannah and Parker 2007). We report here on the development of histologically-based length and age at maturity data for female quillback rockfish (Sebastes maliger) and length at maturity data for female china rockfish (S. nebulosus). Close