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• 781. [Article] Klamath Mountains Province Steelhead Project, 2001-02 Annual Report Report Number: OPSW-ODFW-2004-08

  Abstract -- The steelhead supplement to the Oregon Plan for Salmon and Watersheds (OSPW) is intended to maintain wild steelhead populations in Oregon at sustainable and productive levels that provide substantial ...

  Citation × Citation Citation Abstract Copy Title: Klamath Mountains Province Steelhead Project, 2001-02 Annual Report Report Number: OPSW-ODFW-2004-08 Abstract -- The steelhead supplement to the Oregon Plan for Salmon and Watersheds (OSPW) is intended to maintain wild steelhead populations in Oregon at sustainable and productive levels that provide substantial environmental, cultural, and economic benefits. The OSPW attempts to better define "sustainable and productive" by committing the Oregon Department of Fish and Wildlife (ODFW) to establish "Population Health Goals" for each Evolutionary Significant Unit (ESU) of wild steelhead within the state. In addition, section ODFW IB1S of the plan calls for ODFW to assess adult escapement and juvenile production of wild steelhead in each ESU. The National Marine Fisheries Service identified seven ESUs for steelhead in Oregon and concluded that steelhead produced in coastal basins between Cape Blanco in southern Oregon and the Klamath River Basin in northern California constitutes one ESU. This area closely corresponds to the geologic boundaries of the Klamath Mountains Province (KMP). Steelhead in the KMP differ from those in adjoining areas because of distinctive life history and genetic characteristics (Busby et al. 1994). Primary differences in life history parameters have been identified for wild KMP steelhead. Summer steelhead and winter steelhead differ in time of return as adults, tendency to return to fresh water on a false spawning migration (the "half-pounder" run), age at ocean entry, growth rate and migration patterns of juveniles in fresh water (ODFW 1990; ODFW 1994). As a result of these differences, separate health goals seem warranted for summer and winter steelhead populations. Winter steelhead inhabit streams throughout the KMP, while summer steelhead are found only in a portion of the Rogue River Basin. However, the distribution of summer and winter steelhead overlap in major areas of the Rogue River Basin (Everest 1973) and, as juveniles of the respective races cannot be differentiated, some population health goals have to apply to both races. The status of wild steelhead in the Klamath Mountains Province ESU is not readily apparent from historic sources of information. Uncertainty about resource status, coupled with a comprehensive conservation plan developed by Oregon and the termination of wild fish harvest in almost all KMP streams, lead the National Marine Fisheries Service (NMFS), in 1998, to defer a listing of KMP steelhead under the Endangered Species Act. On 30 March, 2001, NMFS announced that, after a review of new information, that an Endangered Species Act listing was not warranted for KMP steelhead. In 2002, ODFW adopted new methods to monitor steelhead populations on the Oregon coast. Allied with the decision, ODFW decided to terminate the KMP steelhead project. Consequently, this report presents findings from the third, and final, year of the project. The goal of the project was to develop and implement assessment methods to determine the status of wild steelhead in the Oregon portion of the KMP. Project objectives included (1) develop population health goals and allied monitoring methods and (2) determine resource status in relation to health goals Satterthwaite (2002a). Directed sampling began in 1999 and findings from the first two years of the project were reported by Satterthwaite (2002b) and Satterthwaite (2003). Title: Klamath Mountains Province Steelhead Project, 2001-02 Annual Report Report Number: OPSW-ODFW-2004-08 Abstract -- The steelhead supplement to the Oregon Plan for Salmon and Watersheds (OSPW) is intended to maintain wild steelhead populations in Oregon at sustainable and productive levels that provide substantial environmental, cultural, and economic benefits. The OSPW attempts to better define "sustainable and productive" by committing the Oregon Department of Fish and Wildlife (ODFW) to establish "Population Health Goals" for each Evolutionary Significant Unit (ESU) of wild steelhead within the state. In addition, section ODFW IB1S of the plan calls for ODFW to assess adult escapement and juvenile production of wild steelhead in each ESU. The National Marine Fisheries Service identified seven ESUs for steelhead in Oregon and concluded that steelhead produced in coastal basins between Cape Blanco in southern Oregon and the Klamath River Basin in northern California constitutes one ESU. This area closely corresponds to the geologic boundaries of the Klamath Mountains Province (KMP). Steelhead in the KMP differ from those in adjoining areas because of distinctive life history and genetic characteristics (Busby et al. 1994). Primary differences in life history parameters have been identified for wild KMP steelhead. Summer steelhead and winter steelhead differ in time of return as adults, tendency to return to fresh water on a false spawning migration (the "half-pounder" run), age at ocean entry, growth rate and migration patterns of juveniles in fresh water (ODFW 1990; ODFW 1994). As a result of these differences, separate health goals seem warranted for summer and winter steelhead populations. Winter steelhead inhabit streams throughout the KMP, while summer steelhead are found only in a portion of the Rogue River Basin. However, the distribution of summer and winter steelhead overlap in major areas of the Rogue River Basin (Everest 1973) and, as juveniles of the respective races cannot be differentiated, some population health goals have to apply to both races. The status of wild steelhead in the Klamath Mountains Province ESU is not readily apparent from historic sources of information. Uncertainty about resource status, coupled with a comprehensive conservation plan developed by Oregon and the termination of wild fish harvest in almost all KMP streams, lead the National Marine Fisheries Service (NMFS), in 1998, to defer a listing of KMP steelhead under the Endangered Species Act. On 30 March, 2001, NMFS announced that, after a review of new information, that an Endangered Species Act listing was not warranted for KMP steelhead. In 2002, ODFW adopted new methods to monitor steelhead populations on the Oregon coast. Allied with the decision, ODFW decided to terminate the KMP steelhead project. Consequently, this report presents findings from the third, and final, year of the project. The goal of the project was to develop and implement assessment methods to determine the status of wild steelhead in the Oregon portion of the KMP. Project objectives included (1) develop population health goals and allied monitoring methods and (2) determine resource status in relation to health goals Satterthwaite (2002a). Directed sampling began in 1999 and findings from the first two years of the project were reported by Satterthwaite (2002b) and Satterthwaite (2003). Close

• 782. [Article] Oregon Coast Coho Habitat Assessment 1998-2003 Report Number: OPSW-ODFW-2005-5

  Abstract -- In November 2003, the State of Oregon began a comprehensive review of coho and their habitat in NOAA Fisheries’ Oregon Coastal Coho Evolutionary Significant Unit (ESU). The purpose of the review ...

  Citation × Citation Citation Abstract Copy Title: Oregon Coast Coho Habitat Assessment 1998-2003 Report Number: OPSW-ODFW-2005-5 Abstract -- In November 2003, the State of Oregon began a comprehensive review of coho and their habitat in NOAA Fisheries’ Oregon Coastal Coho Evolutionary Significant Unit (ESU). The purpose of the review is threefold: 1) provide an analysis of the current status and trend in coho populations, their habitat, and related threats; 2) provide NOAA Fisheries with information it requires to determine whether formalized conservation efforts within the ESU justify not listing coho under the Endangered Species Act as outlined in their Policy for Evaluation of Conservation Efforts; and 3) provide information to state agencies, watershed councils, and others participating in the Oregon Plan for Salmon and Watersheds (OPSW) so they may assess the success of their OPSW programs and modify them where necessary to better achieve their objectives (i.e. adaptive management). This report describes the current status and trend of instream physical habitat for coho in the ESU as well as summarizes and evaluates instream habitat restoration activities conducted from 1997-2003. Title: Oregon Coast Coho Habitat Assessment 1998-2003 Report Number: OPSW-ODFW-2005-5 Abstract -- In November 2003, the State of Oregon began a comprehensive review of coho and their habitat in NOAA Fisheries’ Oregon Coastal Coho Evolutionary Significant Unit (ESU). The purpose of the review is threefold: 1) provide an analysis of the current status and trend in coho populations, their habitat, and related threats; 2) provide NOAA Fisheries with information it requires to determine whether formalized conservation efforts within the ESU justify not listing coho under the Endangered Species Act as outlined in their Policy for Evaluation of Conservation Efforts; and 3) provide information to state agencies, watershed councils, and others participating in the Oregon Plan for Salmon and Watersheds (OPSW) so they may assess the success of their OPSW programs and modify them where necessary to better achieve their objectives (i.e. adaptive management). This report describes the current status and trend of instream physical habitat for coho in the ESU as well as summarizes and evaluates instream habitat restoration activities conducted from 1997-2003. Close

• 783. [Article] Stream Habitat Conditions in Western Oregon 2005 Monitoring Report Report Number: OPSW-ODFW-2007-5

  Abstract -- Monitoring programs under the Oregon Plan for Salmon and Watersheds were designed to assess the status and trend in fish populations and aquatic habitat in Oregon’s coastal basins. Although ...

  Citation × Citation Citation Abstract Copy Title: Stream Habitat Conditions in Western Oregon 2005 Monitoring Report Report Number: OPSW-ODFW-2007-5 Abstract -- Monitoring programs under the Oregon Plan for Salmon and Watersheds were designed to assess the status and trend in fish populations and aquatic habitat in Oregon’s coastal basins. Although the Oregon Plan for Salmon and Watersheds was initiated in response to the petition to list Oregon coastal coho salmon (Oncorhynchus kisutch) as threatened under the Endangered Species Act (ESA), monitoring was subsequently expanded to include other salmonids. Through coordinated surveys we are able to evaluate freshwater habitat, fish distribution, and abundance of juvenile and adult coho salmon and steelhead trout. The habitat survey project has the broadest geographic scope of inference and ties to other program components as well – basin surveys, surveys at habitat restoration sites, adult and juvenile coho surveys, and life cycle watersheds (Flitcroft et al. 2002). The Oregon Plan facilitated cooperation and partnerships to study the contemporary life history dynamics of coho salmon in the Oregon coastal ESU (Evolutionary Significant Unit). A viability and status assessment of Oregon coastal Coho (Chilcote 2005) and the Conservation Plan for the Oregon Coast Coho Evolutionary Significant Unit (Nicholas 2006) evaluated the relationship of aquatic habitat to the productivity of coho salmon populations and recommended actions to promote recovery. The habitat portion of the viability assessment was based on a review of aquatic and riparian habitat collected by the Aquatic Inventories Project (ODFW) from 1990 to 2004 (Rodgers et al. 2005). The authors of the habitat assessment (Rodgers et al 2005) and viability assessment (Chilcote 2005) concluded that coho productivity in 22 coastal coho populations was limited by the complexity of stream habitat used by juvenile coho during their first winter of freshwater residence. The term “stream complexity” integrates geomorphic and structural characteristics of streams and associated aquatic habitat. Complex geomorphic features may be observed in low gradient streams flowing through wide valley floors with multiple channels and off-channel habitats. Structural complexity refers to the size and configuration of pools, large wood pieces and jams, substrate, and undercut banks. The combination of geomorphic and structural features provides cover and refugia during high winter flows for juvenile coho. Stream reaches that can or have the potential to create these conditions are commonly located in lower reaches of moderate size streams in areas with wide valley floors and are considered to contain high quality habitat for juvenile coho. Burnett et al. (2007) developed spatial models to estimate high-quality habitat rearing potential, termed intrinsic potential, in coastal streams. A stream’s intrinsic potential was modeled using valley width, gradient, and stream flow. Historically, streams identified as having high intrinsic potential may have been the most productive for juvenile coho salmon; restoration of these reaches may be the key to recovery of coho salmon. The viability assessment and Coho Plan recommend that we monitor the trends in total amount and spatial distribution of these habitats in coastal drainages. This report discusses the findings from aquatic habitat surveys conducted in summer 2005 in coastal drainages. Our objectives are to describe and compare channel morphology, instream habitat and complexity, and riparian conditions in all wadeable streams in five monitoring areas. The sample design permitted us to post stratify the sample sites into three additional frames: sites within coho and steelhead distribution, sites outside coho distribution, and sites within high intrinsic potential for coho. We also used two habitat models to integrate habitat attributes to describe the habitat quality and capacity for different life stages of juvenile coho and steelhead. Title: Stream Habitat Conditions in Western Oregon 2005 Monitoring Report Report Number: OPSW-ODFW-2007-5 Abstract -- Monitoring programs under the Oregon Plan for Salmon and Watersheds were designed to assess the status and trend in fish populations and aquatic habitat in Oregon’s coastal basins. Although the Oregon Plan for Salmon and Watersheds was initiated in response to the petition to list Oregon coastal coho salmon (Oncorhynchus kisutch) as threatened under the Endangered Species Act (ESA), monitoring was subsequently expanded to include other salmonids. Through coordinated surveys we are able to evaluate freshwater habitat, fish distribution, and abundance of juvenile and adult coho salmon and steelhead trout. The habitat survey project has the broadest geographic scope of inference and ties to other program components as well – basin surveys, surveys at habitat restoration sites, adult and juvenile coho surveys, and life cycle watersheds (Flitcroft et al. 2002). The Oregon Plan facilitated cooperation and partnerships to study the contemporary life history dynamics of coho salmon in the Oregon coastal ESU (Evolutionary Significant Unit). A viability and status assessment of Oregon coastal Coho (Chilcote 2005) and the Conservation Plan for the Oregon Coast Coho Evolutionary Significant Unit (Nicholas 2006) evaluated the relationship of aquatic habitat to the productivity of coho salmon populations and recommended actions to promote recovery. The habitat portion of the viability assessment was based on a review of aquatic and riparian habitat collected by the Aquatic Inventories Project (ODFW) from 1990 to 2004 (Rodgers et al. 2005). The authors of the habitat assessment (Rodgers et al 2005) and viability assessment (Chilcote 2005) concluded that coho productivity in 22 coastal coho populations was limited by the complexity of stream habitat used by juvenile coho during their first winter of freshwater residence. The term “stream complexity” integrates geomorphic and structural characteristics of streams and associated aquatic habitat. Complex geomorphic features may be observed in low gradient streams flowing through wide valley floors with multiple channels and off-channel habitats. Structural complexity refers to the size and configuration of pools, large wood pieces and jams, substrate, and undercut banks. The combination of geomorphic and structural features provides cover and refugia during high winter flows for juvenile coho. Stream reaches that can or have the potential to create these conditions are commonly located in lower reaches of moderate size streams in areas with wide valley floors and are considered to contain high quality habitat for juvenile coho. Burnett et al. (2007) developed spatial models to estimate high-quality habitat rearing potential, termed intrinsic potential, in coastal streams. A stream’s intrinsic potential was modeled using valley width, gradient, and stream flow. Historically, streams identified as having high intrinsic potential may have been the most productive for juvenile coho salmon; restoration of these reaches may be the key to recovery of coho salmon. The viability assessment and Coho Plan recommend that we monitor the trends in total amount and spatial distribution of these habitats in coastal drainages. This report discusses the findings from aquatic habitat surveys conducted in summer 2005 in coastal drainages. Our objectives are to describe and compare channel morphology, instream habitat and complexity, and riparian conditions in all wadeable streams in five monitoring areas. The sample design permitted us to post stratify the sample sites into three additional frames: sites within coho and steelhead distribution, sites outside coho distribution, and sites within high intrinsic potential for coho. We also used two habitat models to integrate habitat attributes to describe the habitat quality and capacity for different life stages of juvenile coho and steelhead. Close

• 784. [Article] Assessment of Oregon Coastal Adult Winter Steelhead – Redd Surveys 2007 Report Number: OPSW-ODFW-2007-09

  Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated a project to monitor spawning winter steelhead (Oncorhynchus mykiss) in coastal ...

  Citation × Citation Citation Abstract Copy Title: Assessment of Oregon Coastal Adult Winter Steelhead – Redd Surveys 2007 Report Number: OPSW-ODFW-2007-09 Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated a project to monitor spawning winter steelhead (Oncorhynchus mykiss) in coastal Oregon streams in 2003. This project is designed to assess the yearly status and trend, presence of hatchery fish, and distribution of winter steelhead spawners in six coastal Monitoring Areas (MA) in two Distinct Population Segments (DPS) (Figure 1). A spatially balanced probabilistic sampling design (Stevens 2002) was used to select survey sites across a stream network of winter steelhead spawning habitat. Monitoring of winter steelhead abundance is based on counts of redds instead of live or dead fish, in accordance with prior work conducted by ODFW in Oregon coastal streams (Susac and Jacobs 1999). Repeat visits to each site from February through May generated a total redd count for each survey. Redds were marked with colored rocks and flagging to prevent re-counting, during subsequent surveys. The survey interval of once every fourteen days is based on prior research (Susac and Jacobs 1999). Specific descriptions of project protocols can be found in the annual survey procedures manual (ODFW 2007). More information on methods and study background is available in Suring (In Prep.). Title: Assessment of Oregon Coastal Adult Winter Steelhead – Redd Surveys 2007 Report Number: OPSW-ODFW-2007-09 Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated a project to monitor spawning winter steelhead (Oncorhynchus mykiss) in coastal Oregon streams in 2003. This project is designed to assess the yearly status and trend, presence of hatchery fish, and distribution of winter steelhead spawners in six coastal Monitoring Areas (MA) in two Distinct Population Segments (DPS) (Figure 1). A spatially balanced probabilistic sampling design (Stevens 2002) was used to select survey sites across a stream network of winter steelhead spawning habitat. Monitoring of winter steelhead abundance is based on counts of redds instead of live or dead fish, in accordance with prior work conducted by ODFW in Oregon coastal streams (Susac and Jacobs 1999). Repeat visits to each site from February through May generated a total redd count for each survey. Redds were marked with colored rocks and flagging to prevent re-counting, during subsequent surveys. The survey interval of once every fourteen days is based on prior research (Susac and Jacobs 1999). Specific descriptions of project protocols can be found in the annual survey procedures manual (ODFW 2007). More information on methods and study background is available in Suring (In Prep.). Close

• 785. [Article] Abundance Monitoring of Juvenile Salmonids In Coastal Oregon and Lower Columbia Streams, 2008 Report Number: OPSW-ODFW-2009-1

  Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated this project in 1998 to monitor the status and trend in abundance and distribution ...

  Citation × Citation Citation Abstract Copy Title: Abundance Monitoring of Juvenile Salmonids In Coastal Oregon and Lower Columbia Streams, 2008 Report Number: OPSW-ODFW-2009-1 Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated this project in 1998 to monitor the status and trend in abundance and distribution of juvenile coho salmon (Oncorhynchus kisutch) in coastal Oregon streams. This report summarizes the data collected during the summer of 2008 and, for coho salmon, compares it to data previously collected. The project originally surveyed only 1st-3rd order (tributary) streams but was expanded in 2002 to include juvenile steelhead (Oncorhynchus mykiss) and 4th-6th order (mainstem) rearing areas and in 2006 to the Oregon portion of the Lower Columbia River coho evolutionarily significant unit (ESU) (Figure 1). The sampling frame is intended to encompass all non-tidal coho and steelhead rearing habitat. The original 100k stream layer frame was replaced by a 24k frame in 2007. A Generalized Random Tessellation Stratified design (GRTS) (Stevens 2002) was used to create a spatially balanced, random point distribution. Sites were stratified by Monitoring Area (MA) and stream order (Table 1). A detailed description of the sampling frames and survey designs are found in Jepsen and Rodgers (2004) and Jepsen and Leader (2007). Field crews snorkeled all pools meeting the size criteria (6 m2 in surface area and 40 cm in maximum depth) in one kilometer of stream encompassing the GRTS point. Snorkeling was conducted during the minimum flow period from July to September using a single pass of one to four snorkelers, depending on stream width. In each pool counts were made of juvenile coho, Chinook, steelhead 90 mm, and cutthroat 90 mm. Presence was noted for dace, shiners, and trout < 90 mm. Sites with poor water clarity or quality were electrofished using a single pass without block nets to determine presence for coho, steelhead and cutthroat in each pool. To assess repeatability and quality control supervisory staff resurveyed 10% of tributary sites in each MA. Data were summarized by MA and stream order for analyses. Average pool density and percent pool occupancy for each site was averaged by MA. The percent of sites with at least one fish and with >0.7 coho/m2 are reported for each MA. 0.7 coho/m2 is regarded as full seeding after Nickelson et al. (1992) who reported full seeding based on electrofishing as 1.0 coho/m2 and Rodgers et al. (1992) who found that snorkelers observed 70% of the coho counted by electrofishing. CDFs, variances, and confidence intervals were created using tools developed by the EMAP Design and Analysis Team (EPA 2009). Title: Abundance Monitoring of Juvenile Salmonids In Coastal Oregon and Lower Columbia Streams, 2008 Report Number: OPSW-ODFW-2009-1 Abstract -- As part of the Oregon Plan for Salmon and Watersheds, the Oregon Department of Fish and Wildlife (ODFW) initiated this project in 1998 to monitor the status and trend in abundance and distribution of juvenile coho salmon (Oncorhynchus kisutch) in coastal Oregon streams. This report summarizes the data collected during the summer of 2008 and, for coho salmon, compares it to data previously collected. The project originally surveyed only 1st-3rd order (tributary) streams but was expanded in 2002 to include juvenile steelhead (Oncorhynchus mykiss) and 4th-6th order (mainstem) rearing areas and in 2006 to the Oregon portion of the Lower Columbia River coho evolutionarily significant unit (ESU) (Figure 1). The sampling frame is intended to encompass all non-tidal coho and steelhead rearing habitat. The original 100k stream layer frame was replaced by a 24k frame in 2007. A Generalized Random Tessellation Stratified design (GRTS) (Stevens 2002) was used to create a spatially balanced, random point distribution. Sites were stratified by Monitoring Area (MA) and stream order (Table 1). A detailed description of the sampling frames and survey designs are found in Jepsen and Rodgers (2004) and Jepsen and Leader (2007). Field crews snorkeled all pools meeting the size criteria (6 m2 in surface area and 40 cm in maximum depth) in one kilometer of stream encompassing the GRTS point. Snorkeling was conducted during the minimum flow period from July to September using a single pass of one to four snorkelers, depending on stream width. In each pool counts were made of juvenile coho, Chinook, steelhead 90 mm, and cutthroat 90 mm. Presence was noted for dace, shiners, and trout < 90 mm. Sites with poor water clarity or quality were electrofished using a single pass without block nets to determine presence for coho, steelhead and cutthroat in each pool. To assess repeatability and quality control supervisory staff resurveyed 10% of tributary sites in each MA. Data were summarized by MA and stream order for analyses. Average pool density and percent pool occupancy for each site was averaged by MA. The percent of sites with at least one fish and with >0.7 coho/m2 are reported for each MA. 0.7 coho/m2 is regarded as full seeding after Nickelson et al. (1992) who reported full seeding based on electrofishing as 1.0 coho/m2 and Rodgers et al. (1992) who found that snorkelers observed 70% of the coho counted by electrofishing. CDFs, variances, and confidence intervals were created using tools developed by the EMAP Design and Analysis Team (EPA 2009). Close

• 786. [Article] Recovery of Wild Coho Salmon in Salmon River Basin, 2008 Report Number: OPSW-ODFW-2009-10

  Abstract -- Recovery and conservation of naturally self-sustaining salmon populations is a central goal of the Oregon Plan for Salmon and Watersheds. In 1998, the Oregon Department of Fish and Wildlife ...

  Citation × Citation Citation Abstract Copy Title: Recovery of Wild Coho Salmon in Salmon River Basin, 2008 Report Number: OPSW-ODFW-2009-10 Abstract -- Recovery and conservation of naturally self-sustaining salmon populations is a central goal of the Oregon Plan for Salmon and Watersheds. In 1998, the Oregon Department of Fish and Wildlife (ODFW) initiated a comprehensive program to monitor the status of coho salmon (Oncorhynchus kisutch) populations and aquatic habitat in coastal drainages of Oregon (OWEB 2003). A 2005 assessment by ODFW concluded that Oregon coastal coho were viable at the scale of the Evolutionary Significant Unit (ESU) and demonstrated resilience in response to improving ocean conditions. Yet 7 of 21 (33%) individual populations within the ESU failed one or more of five criteria used to assess viability (Chilcote et al. 2005), and it is uncertain whether productivity levels across the ESU will recover sufficiently to withstand future periods of poor ocean conditions. The coho population in Salmon River was the only population in the ESU to fail all five viability criteria. Uncertainty remains about the response of Oregon coastal coho salmon to different combinations of freshwater and marine limiting factors, complicating recovery efforts (Lawson 1993; Lawson et al. 2004; IMST 2006). Such uncertainty cannot be resolved entirely by existing Oregon Plan monitoring programs, which target only a portion of the habitats and coho salmon life stages in large river basins, and with few exceptions (e.g., Johnson et al. 2005), were not designed to test population responses to individual management manipulations. In 2007, in response to the failure of viability criteria, ODFW managers discontinued releases of hatchery coho salmon into Salmon River as one of the primary management actions under the Oregon Conservation Plan for the Oregon Coast Coho Evolutionarily Significant Unit (hereafter “coho plan,” Nicholas 2006). This change affords the first opportunity in Oregon to monitor the results of a large scale experiment in removing hatchery coho salmon from a basin for at least four generations (twelve years). Hatchery production has been a centerpiece of salmon management for decades, but rarely has full recovery from hatchery influence been given a chance to succeed. Salmon River offers a test basin to explore whether an independent population of coho salmon can recover from a prolonged period of very low abundance following removal of the primary factor limiting productivity. Here we describe the first year of a study to monitor the dynamics of the coho salmon population in the Salmon River basin on the central Oregon coast and to determine whether management changes targeting both hatchery influence and stream habitat complexity improve population viability. This research will validate assumptions about factors limiting coho recovery and determine whether recovery measures proposed by the Coho Plan have been effective. Our research is designed to document changes in population abundance, distribution, and life history structure of coho salmon following the removal of hatchery coho salmon from the watershed. It integrates adult, juvenile, and habitat components to establish links and describe variability between juvenile performance and adult recovery. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will establish the link between productivity and survival at each salmon life stage and recovery of the adult population. From these indicators, we will determine the potential resiliency of coho salmon, detail the biological benefits/tradeoffs of returning the ecosystem to natural salmon production, and assess whether supplementation should remain an option in Salmon River. As a conceptual framework, our research design and analyses are guided by the “viable salmonid population” criteria identified by McElhany (2000) and modified by Chilcote et al. (2005) and Nicholas (2006), including abundance, productivity, distribution, diversity, and habitat quality. The results of our new research will be integrated with habitat survey and adult population data collected under the existing Oregon Plan monitoring program and coho salmon population and life history data available from previous Salmon River surveys (Mullen 1978, 1979; Cornwell et al. 2001; Bottom et al 2005; Volk et al. in review). Together these data will address four principal objectives: 1. Quantify viability of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether viability of the Salmon River coho population is limited by quantity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin and estimate the relative contributions of alternate juvenile life history to adult returns. 4. Determine salmonid use and benefits of restored tidal wetlands before and after hatchery coho salmon are removed from Salmon River. By synthesizing historic data with new information for the Salmon River basin, we will compare population structure during three distinct periods – pre-hatchery (1974-77), hatchery (1990-2008), and post-hatchery (2009-2013). This annual report discusses the activities and findings from 2008, the first year of the multi-year project, including coho salmon distribution and abundance on the Salmon River spawning grounds, juvenile abundance and distribution in the watershed and estuary, migration timing, and life history diversity. Title: Recovery of Wild Coho Salmon in Salmon River Basin, 2008 Report Number: OPSW-ODFW-2009-10 Abstract -- Recovery and conservation of naturally self-sustaining salmon populations is a central goal of the Oregon Plan for Salmon and Watersheds. In 1998, the Oregon Department of Fish and Wildlife (ODFW) initiated a comprehensive program to monitor the status of coho salmon (Oncorhynchus kisutch) populations and aquatic habitat in coastal drainages of Oregon (OWEB 2003). A 2005 assessment by ODFW concluded that Oregon coastal coho were viable at the scale of the Evolutionary Significant Unit (ESU) and demonstrated resilience in response to improving ocean conditions. Yet 7 of 21 (33%) individual populations within the ESU failed one or more of five criteria used to assess viability (Chilcote et al. 2005), and it is uncertain whether productivity levels across the ESU will recover sufficiently to withstand future periods of poor ocean conditions. The coho population in Salmon River was the only population in the ESU to fail all five viability criteria. Uncertainty remains about the response of Oregon coastal coho salmon to different combinations of freshwater and marine limiting factors, complicating recovery efforts (Lawson 1993; Lawson et al. 2004; IMST 2006). Such uncertainty cannot be resolved entirely by existing Oregon Plan monitoring programs, which target only a portion of the habitats and coho salmon life stages in large river basins, and with few exceptions (e.g., Johnson et al. 2005), were not designed to test population responses to individual management manipulations. In 2007, in response to the failure of viability criteria, ODFW managers discontinued releases of hatchery coho salmon into Salmon River as one of the primary management actions under the Oregon Conservation Plan for the Oregon Coast Coho Evolutionarily Significant Unit (hereafter “coho plan,” Nicholas 2006). This change affords the first opportunity in Oregon to monitor the results of a large scale experiment in removing hatchery coho salmon from a basin for at least four generations (twelve years). Hatchery production has been a centerpiece of salmon management for decades, but rarely has full recovery from hatchery influence been given a chance to succeed. Salmon River offers a test basin to explore whether an independent population of coho salmon can recover from a prolonged period of very low abundance following removal of the primary factor limiting productivity. Here we describe the first year of a study to monitor the dynamics of the coho salmon population in the Salmon River basin on the central Oregon coast and to determine whether management changes targeting both hatchery influence and stream habitat complexity improve population viability. This research will validate assumptions about factors limiting coho recovery and determine whether recovery measures proposed by the Coho Plan have been effective. Our research is designed to document changes in population abundance, distribution, and life history structure of coho salmon following the removal of hatchery coho salmon from the watershed. It integrates adult, juvenile, and habitat components to establish links and describe variability between juvenile performance and adult recovery. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will establish the link between productivity and survival at each salmon life stage and recovery of the adult population. From these indicators, we will determine the potential resiliency of coho salmon, detail the biological benefits/tradeoffs of returning the ecosystem to natural salmon production, and assess whether supplementation should remain an option in Salmon River. As a conceptual framework, our research design and analyses are guided by the “viable salmonid population” criteria identified by McElhany (2000) and modified by Chilcote et al. (2005) and Nicholas (2006), including abundance, productivity, distribution, diversity, and habitat quality. The results of our new research will be integrated with habitat survey and adult population data collected under the existing Oregon Plan monitoring program and coho salmon population and life history data available from previous Salmon River surveys (Mullen 1978, 1979; Cornwell et al. 2001; Bottom et al 2005; Volk et al. in review). Together these data will address four principal objectives: 1. Quantify viability of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether viability of the Salmon River coho population is limited by quantity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin and estimate the relative contributions of alternate juvenile life history to adult returns. 4. Determine salmonid use and benefits of restored tidal wetlands before and after hatchery coho salmon are removed from Salmon River. By synthesizing historic data with new information for the Salmon River basin, we will compare population structure during three distinct periods – pre-hatchery (1974-77), hatchery (1990-2008), and post-hatchery (2009-2013). This annual report discusses the activities and findings from 2008, the first year of the multi-year project, including coho salmon distribution and abundance on the Salmon River spawning grounds, juvenile abundance and distribution in the watershed and estuary, migration timing, and life history diversity. Close

• 787. [Article] Smith River Steelhead and Coho Monitoring Verification Study, 2007 Report Number: OPSW-ODFW-2009-11

  Abstract -- Monitoring the status of salmonids in Oregon coastal streams is an important component of the Oregon Department of Fish and Wildlife’s (ODFW) contribution to the Oregon Plan for Salmon and ...

  Citation × Citation Citation Abstract Copy Title: Smith River Steelhead and Coho Monitoring Verification Study, 2007 Report Number: OPSW-ODFW-2009-11 Abstract -- Monitoring the status of salmonids in Oregon coastal streams is an important component of the Oregon Department of Fish and Wildlife’s (ODFW) contribution to the Oregon Plan for Salmon and Watersheds. Since 1998, ODFW has implemented a probabilistic sampling design (Stevens 2002) to monitor adult and juvenile coho in Oregon coastal streams. In 2002, ODFW expanded its monitoring program to include steelhead. Monitoring is occurring coast wide and relies on the Environmental Monitoring and Assessment Program (EMAP, Stevens and Olsen 1999) for site selection and to produce fish abundance metrics at large spatial scales. Juvenile monitoring is conducted using snorkel survey protocols. The Smith River Steelhead and Coho Monitoring Verification Study is an effort to evaluate how well visual counts compare with removal estimates as a monitoring tool at the basin scale and to provide information on the relationship of monitoring data collected coast wide to actual populations. This report will summarize juvenile salmonid data collected by snorkeling and electrofishing in the Smith River basin during the summer of 2007 and provide a comparative analysis of several years’ data of how the estimates from the two methods correspond to each other and to the spawning survey estimates of adult fish above Smith River Falls. Information on the relationship of coast wide snorkel counts on the basin scale to actual population status will be presented in a synthesis report covering all years of this study. Title: Smith River Steelhead and Coho Monitoring Verification Study, 2007 Report Number: OPSW-ODFW-2009-11 Abstract -- Monitoring the status of salmonids in Oregon coastal streams is an important component of the Oregon Department of Fish and Wildlife’s (ODFW) contribution to the Oregon Plan for Salmon and Watersheds. Since 1998, ODFW has implemented a probabilistic sampling design (Stevens 2002) to monitor adult and juvenile coho in Oregon coastal streams. In 2002, ODFW expanded its monitoring program to include steelhead. Monitoring is occurring coast wide and relies on the Environmental Monitoring and Assessment Program (EMAP, Stevens and Olsen 1999) for site selection and to produce fish abundance metrics at large spatial scales. Juvenile monitoring is conducted using snorkel survey protocols. The Smith River Steelhead and Coho Monitoring Verification Study is an effort to evaluate how well visual counts compare with removal estimates as a monitoring tool at the basin scale and to provide information on the relationship of monitoring data collected coast wide to actual populations. This report will summarize juvenile salmonid data collected by snorkeling and electrofishing in the Smith River basin during the summer of 2007 and provide a comparative analysis of several years’ data of how the estimates from the two methods correspond to each other and to the spawning survey estimates of adult fish above Smith River Falls. Information on the relationship of coast wide snorkel counts on the basin scale to actual population status will be presented in a synthesis report covering all years of this study. Close

• 788. [Article] Effectiveness Monitoring Report for the Western Oregon Stream Restoration Program, 1999-2008 Report Number: OPSW-ODFW-2010-6

  Abstract -- State and federal agencies have invested millions of dollars to restore streams and watersheds in the Pacific Northwest over the past two decades. In Oregon alone, over 500 million dollars ...

  Citation × Citation Citation Abstract Copy Title: Effectiveness Monitoring Report for the Western Oregon Stream Restoration Program, 1999-2008 Report Number: OPSW-ODFW-2010-6 Abstract -- State and federal agencies have invested millions of dollars to restore streams and watersheds in the Pacific Northwest over the past two decades. In Oregon alone, over 500 million dollars has been spent on completed projects from 1995 to 2007 (Oregon Watershed Enhancement Board 2009). Restoration practitioners have distributed the investment among watershed scale activities such as road repair, dam removal, and upland management, and stream scale activities such as passage, instream complexity, and riparian plantings. The Western Oregon Stream Restoration Program (WOSRP) was established to work in cooperation with private and corporate landowners to restore stream habitat for juvenile and adult salmonids. In addition to the WOSRP, the Oregon Watershed Enhancement Board (OWEB) funds restoration projects with local watershed councils, who commonly partner with state and federal agencies. Eight WOSRP restoration biologists in Tillamook, Newport, Charleston, Gold Beach, Roseburg, Clackamas, and Salem select sites and implement projects consistent with the criteria described in Thom et al (2001). A monitoring component is integrated in the program, with surveys coordinated and reported by a biologist in Corvallis. The goal of the monitoring program is to assess the long term effectiveness of instream restoration projects implemented by WOSRP, and to evaluate progress towards salmon conservation and recovery goals in Oregon’s coastal basins. The WOSRP restoration sites are distributed throughout the Willamette, Lower Columbia, and coastal drainage's. Restoration treatments added large wood and/or boulders, improved fish passage, planted trees in riparian areas, or were a combination of the three. Large wood was placed in complex jams at intervals throughout the stream to increase stream roughness and complexity. Boulders were sometimes used in conjunction with wood jams to provide stability to the structures, and prevent large wood from moving downstream and posing a hazard to culverts and bridges. Bedrock dominated streams were often treated with boulders to collect gravel and cobble, intended to aggrade the streambed. In the future, large wood may be added to these streams. Fish passage projects opened previously inaccessible habitat to juvenile and/or adult salmonids while riparian plantings and fencing were designed to improve riparian vegetation and bank structure. The project length varied from site to site. Fish passage sites were quite short, but provided access to kilometers of fish habitat, and large wood sites were up to several kilometers in length. Large wood and boulder placement projects have become commonplace in the Pacific Northwest to restore complex stream habitat for juvenile coho and other salmonids (Katz et al. 2007, Roni et al. 2008). Detailed assessments have been published for individual projects or experiments (e.g. Moore and Gregory, 1988, Nickelson et al. 1992, Cederholm et al.1997). More extensive evaluations have used a post treatment design (Hicks et al 1991, Roni and Quinn 2001), but none have used a pre- and post treatment design. In this paper we evaluate habitat changes at 103 restoration projects in western Oregon from pre-treatment to one year post treatment to 6 years following treatment. Projects commonly treated 0.5 – 1 km of stream, but some extended up to 6 km. The projects we evaluated in this paper were treated with large logs, usually arranged in jams, and were not cabled or driven into banks or bottom. As of 2008, the OWEB and WOSRP projects have treated approximately 750 km of stream with large wood (Figure 1), 120 km with boulders, and over 4,000 km of stream have been made accessible by replacing and/or removing culverts. Each year, OWEB receives 210 grant applications for restoration projects. These projects generally adhere to a similar selection process and design, so the results of this study can be expected to apply more broadly within the Pacific Northwest. Roni et al (2008), in a synthesis paper, summarized many of the potential physical benefits of restoration; these include pool depth and frequency, habitat complexity, woody debris, and sediment retention and quality of spawning gravel. Some projects in deeply incised channels have reduced the incision and increased bed elevation. Evaluations of biological responses have been confounded by natural variability of populations, duration of study, or length of stream examined. For example, determination of success based on spawning ground counts is problematic because of variation in ocean survival. However, longer duration and watershed scale studies have shown positive responses of juvenile and adult salmon (Johnson et al 2005). Burnett et al. (2008) conducted a systematic review of peer-reviewed articles to examine the effects of large wood placement on salmonid abundance, growth, or survival, or on overall stream habitat complexity. Few publications were both relevant and met the rigorous standards outlined in their review. Although the review supported short term improvements in habitat complexity, the relationship to salmonid productivity was less definitive. Notable exceptions included Johnson et al. (2005) cited above, and Solazzi et al. (2000). An alternative approach to directly assessing biological response is to model potential changes in abundance or productivity. The Habitat Limiting Factors Model (Reeves et al. 1989, Nickelson et al.1992a, Nickelson 1998) was developed to quantify the carrying capacity of coastal streams for juvenile coho during the summer and winter. Use of this model is appropriate because most of the instream restoration projects in western Oregon were intended to improve habitat for juvenile coho. In this paper, we evaluated the physical response directly, and quantified the potential response of juvenile coho salmon by application of the Habitat Limiting Factors Model. Project effectiveness monitoring requires linking the restoration treatment to improved physical conditions for and biological response of salmon (Katz et al. 2007) and defining desired outcomes (Rumps et al. 2007). Because the WOSRP projects were designed to improve ecological and hydrologic stream function specifically for salmonids, we evaluated 1) retention of wood structures, 2) natural recruitment of additional wood, 3) increase in pool number, area, and depth, 4) retention of gravels and sorting of finer substrates, and 5) increase in channel complexity – secondary channels and off-channel habitats. Biological evaluation was based on estimates of the potential carrying capacity for juvenile coho during the overwinter life stage. The primary objectives of this evaluation are to test for these changes one year following treatment and 6 years following treatment. Secondarily, we evaluated the response of the projects by geographic location and position along the stream network. Previous WOSRP monitoring reports (e.g. Jacobsen and Jones 2003, Jacobsen et al. 2007) have focused on conditions one year following treatment, with relatively few sites assessed 2-3 years following restoration. Since 2003, the restoration projects have increased in complexity – more and larger pieces and jams, and treated more kilometers of stream length per site. The WOSRP program has provided a unique opportunity to evaluate the effects of restoration projects over longer times and broader geographic scales than previously feasible. We have been surveying the restoration sites in both summer and winter to monitor changes in stream habitat and evaluate the success of treatments, such as the placement of wood and/or boulders and fish passage. Surveys are logistically easier to manage in the summer, but surveys conducted during the winter provide a more timely and accurate assessment of over-winter rearing potential for juvenile coho. Because we have paired surveys, we are able to assess the added value of revisits across seasons. We test the hypothesis that habitat characteristics at the restoration sites do not change from summer to winter. The findings permit us to modify the survey program if the information is duplicative, and use the resources in another fashion. Title: Effectiveness Monitoring Report for the Western Oregon Stream Restoration Program, 1999-2008 Report Number: OPSW-ODFW-2010-6 Abstract -- State and federal agencies have invested millions of dollars to restore streams and watersheds in the Pacific Northwest over the past two decades. In Oregon alone, over 500 million dollars has been spent on completed projects from 1995 to 2007 (Oregon Watershed Enhancement Board 2009). Restoration practitioners have distributed the investment among watershed scale activities such as road repair, dam removal, and upland management, and stream scale activities such as passage, instream complexity, and riparian plantings. The Western Oregon Stream Restoration Program (WOSRP) was established to work in cooperation with private and corporate landowners to restore stream habitat for juvenile and adult salmonids. In addition to the WOSRP, the Oregon Watershed Enhancement Board (OWEB) funds restoration projects with local watershed councils, who commonly partner with state and federal agencies. Eight WOSRP restoration biologists in Tillamook, Newport, Charleston, Gold Beach, Roseburg, Clackamas, and Salem select sites and implement projects consistent with the criteria described in Thom et al (2001). A monitoring component is integrated in the program, with surveys coordinated and reported by a biologist in Corvallis. The goal of the monitoring program is to assess the long term effectiveness of instream restoration projects implemented by WOSRP, and to evaluate progress towards salmon conservation and recovery goals in Oregon’s coastal basins. The WOSRP restoration sites are distributed throughout the Willamette, Lower Columbia, and coastal drainage's. Restoration treatments added large wood and/or boulders, improved fish passage, planted trees in riparian areas, or were a combination of the three. Large wood was placed in complex jams at intervals throughout the stream to increase stream roughness and complexity. Boulders were sometimes used in conjunction with wood jams to provide stability to the structures, and prevent large wood from moving downstream and posing a hazard to culverts and bridges. Bedrock dominated streams were often treated with boulders to collect gravel and cobble, intended to aggrade the streambed. In the future, large wood may be added to these streams. Fish passage projects opened previously inaccessible habitat to juvenile and/or adult salmonids while riparian plantings and fencing were designed to improve riparian vegetation and bank structure. The project length varied from site to site. Fish passage sites were quite short, but provided access to kilometers of fish habitat, and large wood sites were up to several kilometers in length. Large wood and boulder placement projects have become commonplace in the Pacific Northwest to restore complex stream habitat for juvenile coho and other salmonids (Katz et al. 2007, Roni et al. 2008). Detailed assessments have been published for individual projects or experiments (e.g. Moore and Gregory, 1988, Nickelson et al. 1992, Cederholm et al.1997). More extensive evaluations have used a post treatment design (Hicks et al 1991, Roni and Quinn 2001), but none have used a pre- and post treatment design. In this paper we evaluate habitat changes at 103 restoration projects in western Oregon from pre-treatment to one year post treatment to 6 years following treatment. Projects commonly treated 0.5 – 1 km of stream, but some extended up to 6 km. The projects we evaluated in this paper were treated with large logs, usually arranged in jams, and were not cabled or driven into banks or bottom. As of 2008, the OWEB and WOSRP projects have treated approximately 750 km of stream with large wood (Figure 1), 120 km with boulders, and over 4,000 km of stream have been made accessible by replacing and/or removing culverts. Each year, OWEB receives 210 grant applications for restoration projects. These projects generally adhere to a similar selection process and design, so the results of this study can be expected to apply more broadly within the Pacific Northwest. Roni et al (2008), in a synthesis paper, summarized many of the potential physical benefits of restoration; these include pool depth and frequency, habitat complexity, woody debris, and sediment retention and quality of spawning gravel. Some projects in deeply incised channels have reduced the incision and increased bed elevation. Evaluations of biological responses have been confounded by natural variability of populations, duration of study, or length of stream examined. For example, determination of success based on spawning ground counts is problematic because of variation in ocean survival. However, longer duration and watershed scale studies have shown positive responses of juvenile and adult salmon (Johnson et al 2005). Burnett et al. (2008) conducted a systematic review of peer-reviewed articles to examine the effects of large wood placement on salmonid abundance, growth, or survival, or on overall stream habitat complexity. Few publications were both relevant and met the rigorous standards outlined in their review. Although the review supported short term improvements in habitat complexity, the relationship to salmonid productivity was less definitive. Notable exceptions included Johnson et al. (2005) cited above, and Solazzi et al. (2000). An alternative approach to directly assessing biological response is to model potential changes in abundance or productivity. The Habitat Limiting Factors Model (Reeves et al. 1989, Nickelson et al.1992a, Nickelson 1998) was developed to quantify the carrying capacity of coastal streams for juvenile coho during the summer and winter. Use of this model is appropriate because most of the instream restoration projects in western Oregon were intended to improve habitat for juvenile coho. In this paper, we evaluated the physical response directly, and quantified the potential response of juvenile coho salmon by application of the Habitat Limiting Factors Model. Project effectiveness monitoring requires linking the restoration treatment to improved physical conditions for and biological response of salmon (Katz et al. 2007) and defining desired outcomes (Rumps et al. 2007). Because the WOSRP projects were designed to improve ecological and hydrologic stream function specifically for salmonids, we evaluated 1) retention of wood structures, 2) natural recruitment of additional wood, 3) increase in pool number, area, and depth, 4) retention of gravels and sorting of finer substrates, and 5) increase in channel complexity – secondary channels and off-channel habitats. Biological evaluation was based on estimates of the potential carrying capacity for juvenile coho during the overwinter life stage. The primary objectives of this evaluation are to test for these changes one year following treatment and 6 years following treatment. Secondarily, we evaluated the response of the projects by geographic location and position along the stream network. Previous WOSRP monitoring reports (e.g. Jacobsen and Jones 2003, Jacobsen et al. 2007) have focused on conditions one year following treatment, with relatively few sites assessed 2-3 years following restoration. Since 2003, the restoration projects have increased in complexity – more and larger pieces and jams, and treated more kilometers of stream length per site. The WOSRP program has provided a unique opportunity to evaluate the effects of restoration projects over longer times and broader geographic scales than previously feasible. We have been surveying the restoration sites in both summer and winter to monitor changes in stream habitat and evaluate the success of treatments, such as the placement of wood and/or boulders and fish passage. Surveys are logistically easier to manage in the summer, but surveys conducted during the winter provide a more timely and accurate assessment of over-winter rearing potential for juvenile coho. Because we have paired surveys, we are able to assess the added value of revisits across seasons. We test the hypothesis that habitat characteristics at the restoration sites do not change from summer to winter. The findings permit us to modify the survey program if the information is duplicative, and use the resources in another fashion. Close

• 789. [Article] Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10

  Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced ...

  Citation × Citation Citation Abstract Copy Title: Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10 Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced salmon have resulted in substantial changes in many hatchery programs. In 2007 the Oregon Department of Fish and Wildlife terminated a 30-year artificial propagation program for coho salmon in the Salmon River basin after a status assessment concluded that wild population viability was threatened by hatchery effects on salmon productivity (Chilcote et al. 2005). Hatchery-reared coho comprised 50-100% of the naturally spawning population in recent years. Low productivity was reflected in a low spawner to recruit ratio, and life-stage specific survival was lower than that of nearby populations. The temporal distribution of adult spawning in the basin was truncated and peaked 1.5 months earlier relative to the pre-hatchery period and adjacent coastal populations. The cessation of hatchery releases into Salmon River not only removed the primary factor believed to limit productivity of the local population, it also constituted a rare management experiment to test whether a naturally-spawning population can recover from a prolonged period of low abundance after interactions with hatchery-produced coho salmon are eliminated. This report summarizes the results of coho population studies at Salmon River for the first three years after the hatchery program was discontinued. The study in Salmon River is timely because ecological interactions between hatchery and wild fish have been implicated in the reduced survival and decreased productivity of wild coho and other salmonid populations (Nickelson 2003, Buhle et al. 2009, Chilcote et al. 2011). Recent studies involving a diversity of salmonid species and watersheds have shown a negative relationship between hatchery spawner abundance and wild population productivity regardless of the duration of hatchery influence (Chilcote et al. 2011). Yet neither the mechanisms of these productivity declines nor their potential reversibility have been investigated. Recent management changes at Salmon River provide an opportunity to experimentally evaluate coho salmon survival and productivity following the elimination of a decades-long hatchery program. The results will provide new insights into the reversibility of hatchery effects and the rate, mechanisms, and trajectory of response by a naturally spawning coho salmon population. Hatchery programs have been shown to change the timing and distribution of naturally spawning adults, but ecological and genetic influences on the spatial structure and life history diversity of juvenile populations are poorly understood. Conventional understanding of the life history of juvenile coho has presumed a relatively fixed pattern of rearing and migration. However, recent studies have found much greater variation in juvenile life history and habitat-use patterns than previously expected (Miller and Sadro 2003, Koski 2009), including evidence that estuaries may play a prominent role in the life histories of some coho salmon populations. A recent study in the Salmon River basin found considerable diversity in the life histories of juvenile Chinook salmon, including extended rearing by fry and other subyearling migrants within the complex network of natural and restored estuarine wetlands (Bottom et al. 2005). Unfortunately, interpretation of juvenile life history variations at Salmon River was confounded by the Chinook hatchery program, which has concentrated spawning activity in the lower river near the hatchery and may directly influence juvenile migration and rearing patterns. Discontinuation of the coho hatchery program at Salmon River provides an opportunity to quantify changes in juvenile life history following the elimination of all hatchery-fish interactions with the naturally spawning population. Such responses may provide important insights into the mechanisms of hatchery influence on wild salmon productivity and population resilience. Our research integrates adult and juvenile life stages, examines linkages to physical habitat conditions in fresh water and the estuary, and describes variability between juvenile performance and adult returns. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will determine productivity and survival at each salmon life stage and monitor the response of the adult population following the cessation of the coho salmon hatchery program. From these indicators, we will determine the potential resiliency of the coho salmon population, and evaluate the biological benefits or tradeoffs of returning the ecosystem to natural salmon production. Our study design encompasses four population phases: (1) pre-hatchery conditions (Mullen 1979), (2) dominance by hatchery-reared spawners (2008), (3) first generation naturally produced juveniles (2009-2011), and (4) second generation naturally produced juveniles (starting in 2012). This research will validate assumptions about factors limiting coho recovery and determine whether recovery actions have been effective. Here, we report on findings from 2008-2010 to address four principal objectives: 1. Quantify life stage specific survival and recruits per spawner ratio of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether the Salmon River coho population is limited by capacity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin, and estimate the relative contributions of various juvenile life histories to adult returns. 4. Determine seasonal use of the Salmon River estuary and its tidally-inundated wetlands by juvenile coho salmon. The field sampling that supported the study on coho salmon also captured Chinook salmon and steelhead and cutthroat trout during routine sampling in the watershed and estuary. This report emphasizes coho salmon results, but also summarizes catch, distribution, and migration data for other salmonids to compare densities and abundances in freshwater and the estuary. Additional results for Chinook, steelhead, and cutthroat are presented in Appendix A. See Stein et al. (2011) for more detailed information on life history diversity, migration patterns, habitat use, and abundance of cutthroat trout. Title: Recovery of Wild Coho Salmon In Salmon River Basin, 2008-2010 Report Number: OPSW-ODFW-2011-10 Abstract -- Hatcheries have been a centerpiece of salmon management in the Pacific Northwest for more than a century but recent evidence of adverse interactions between hatchery and naturally-produced salmon have resulted in substantial changes in many hatchery programs. In 2007 the Oregon Department of Fish and Wildlife terminated a 30-year artificial propagation program for coho salmon in the Salmon River basin after a status assessment concluded that wild population viability was threatened by hatchery effects on salmon productivity (Chilcote et al. 2005). Hatchery-reared coho comprised 50-100% of the naturally spawning population in recent years. Low productivity was reflected in a low spawner to recruit ratio, and life-stage specific survival was lower than that of nearby populations. The temporal distribution of adult spawning in the basin was truncated and peaked 1.5 months earlier relative to the pre-hatchery period and adjacent coastal populations. The cessation of hatchery releases into Salmon River not only removed the primary factor believed to limit productivity of the local population, it also constituted a rare management experiment to test whether a naturally-spawning population can recover from a prolonged period of low abundance after interactions with hatchery-produced coho salmon are eliminated. This report summarizes the results of coho population studies at Salmon River for the first three years after the hatchery program was discontinued. The study in Salmon River is timely because ecological interactions between hatchery and wild fish have been implicated in the reduced survival and decreased productivity of wild coho and other salmonid populations (Nickelson 2003, Buhle et al. 2009, Chilcote et al. 2011). Recent studies involving a diversity of salmonid species and watersheds have shown a negative relationship between hatchery spawner abundance and wild population productivity regardless of the duration of hatchery influence (Chilcote et al. 2011). Yet neither the mechanisms of these productivity declines nor their potential reversibility have been investigated. Recent management changes at Salmon River provide an opportunity to experimentally evaluate coho salmon survival and productivity following the elimination of a decades-long hatchery program. The results will provide new insights into the reversibility of hatchery effects and the rate, mechanisms, and trajectory of response by a naturally spawning coho salmon population. Hatchery programs have been shown to change the timing and distribution of naturally spawning adults, but ecological and genetic influences on the spatial structure and life history diversity of juvenile populations are poorly understood. Conventional understanding of the life history of juvenile coho has presumed a relatively fixed pattern of rearing and migration. However, recent studies have found much greater variation in juvenile life history and habitat-use patterns than previously expected (Miller and Sadro 2003, Koski 2009), including evidence that estuaries may play a prominent role in the life histories of some coho salmon populations. A recent study in the Salmon River basin found considerable diversity in the life histories of juvenile Chinook salmon, including extended rearing by fry and other subyearling migrants within the complex network of natural and restored estuarine wetlands (Bottom et al. 2005). Unfortunately, interpretation of juvenile life history variations at Salmon River was confounded by the Chinook hatchery program, which has concentrated spawning activity in the lower river near the hatchery and may directly influence juvenile migration and rearing patterns. Discontinuation of the coho hatchery program at Salmon River provides an opportunity to quantify changes in juvenile life history following the elimination of all hatchery-fish interactions with the naturally spawning population. Such responses may provide important insights into the mechanisms of hatchery influence on wild salmon productivity and population resilience. Our research integrates adult and juvenile life stages, examines linkages to physical habitat conditions in fresh water and the estuary, and describes variability between juvenile performance and adult returns. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will determine productivity and survival at each salmon life stage and monitor the response of the adult population following the cessation of the coho salmon hatchery program. From these indicators, we will determine the potential resiliency of the coho salmon population, and evaluate the biological benefits or tradeoffs of returning the ecosystem to natural salmon production. Our study design encompasses four population phases: (1) pre-hatchery conditions (Mullen 1979), (2) dominance by hatchery-reared spawners (2008), (3) first generation naturally produced juveniles (2009-2011), and (4) second generation naturally produced juveniles (starting in 2012). This research will validate assumptions about factors limiting coho recovery and determine whether recovery actions have been effective. Here, we report on findings from 2008-2010 to address four principal objectives: 1. Quantify life stage specific survival and recruits per spawner ratio of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether the Salmon River coho population is limited by capacity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin, and estimate the relative contributions of various juvenile life histories to adult returns. 4. Determine seasonal use of the Salmon River estuary and its tidally-inundated wetlands by juvenile coho salmon. The field sampling that supported the study on coho salmon also captured Chinook salmon and steelhead and cutthroat trout during routine sampling in the watershed and estuary. This report emphasizes coho salmon results, but also summarizes catch, distribution, and migration data for other salmonids to compare densities and abundances in freshwater and the estuary. Additional results for Chinook, steelhead, and cutthroat are presented in Appendix A. See Stein et al. (2011) for more detailed information on life history diversity, migration patterns, habitat use, and abundance of cutthroat trout. Close

• 790. [Article] Life History Variability, Habitat Use, and Migratory Behavior of Coastal Cutthroat Trout in the Salmon River, Oregon Report Number: OPSW-ODFW-2012-10

  Abstract -- Coast basins in Oregon support resident and anadromous cutthroat trout (Oncorhynchus clarki clarki). Cutthroat trout isolated above barriers are stream resident, but those with access to river, ...

  Citation × Citation Citation Abstract Copy Title: Life History Variability, Habitat Use, and Migratory Behavior of Coastal Cutthroat Trout in the Salmon River, Oregon Report Number: OPSW-ODFW-2012-10 Abstract -- Coast basins in Oregon support resident and anadromous cutthroat trout (Oncorhynchus clarki clarki). Cutthroat trout isolated above barriers are stream resident, but those with access to river, estuary, and marine environments may express a variety of life history and migratory patterns. Past studies (e.g. Giger 1972, Sumner 1972, Tipping 1981) indicated that estuaries serve primarily as a migratory corridor or short-term rearing environment. However, recent advances in marking and tracking technology have permitted researchers to gain a better understanding of the complex migratory and habitat use patterns of cutthroat. Krentz (2007) conducted studies in Salmon River on the central Oregon coast to explore migratory patterns of cutthroat and examine the role of the estuary as a rearing environment. Coastal cutthroat trout reared for extended periods of time throughout the available channel habitats in Salmon River estuary (Krentz 2007) during spring, summer, and fall. The estuarine resident population appeared to represent a significant portion of the migratory individuals, and included all older age classes. Estuary growth was similar to that of their ocean migrant counterparts, and survival in the estuary was high. Because cutthroat were collected and marked primarily within the estuary (Krentz 2007), it is unclear what portion of the migrant population reared in the estuary relative to the watershed or ocean, or whether the tagged group was representative of the migratory populations. The current study was designed to track a representative sample of the downstream migrant population, and assess the relative success (survival) of the estuary and ocean migrants. Similar studies in the Columbia River documented directed and rapid migration through the estuary (Zydlewski et al. 2008, Hering et al. 2009). With rare exception, cutthroat trout were not observed to rear in the estuary. In addition, many fish disappeared before reaching the ocean and few of the ocean migrants returned to the natal tributary. In this study we replicated the study design used in the Columbia River studies to further comparisons of estuary migration and rearing strategies between the two estuaries. The primary objective of our work in the Salmon River was to increase understanding of coastal cutthroat trout biology and the relationship between stream-resident and migratory, or “sea-run” cutthroat. Here we use the term “sea-run” to indicate migration into the tidally-inundated, or estuarine portions of the Salmon River watershed or to the ocean. Study objectives were to: 1.Estimate the distribution and abundance of coastal cutthroat trout in the Salmon River watershed 2.Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration 3.Describe estuary habitats used by sea-run migrants and characterize behavior within the Salmon River estuary 4.Estimate growth rate of stream and estuary resident cutthroat 5.Estimate estuary and ocean survival of sea-run individuals and document return to estuary and lower river. 6.Compare migratory behavior in Salmon River to that observed in the lower Columbia River Title: Life History Variability, Habitat Use, and Migratory Behavior of Coastal Cutthroat Trout in the Salmon River, Oregon Report Number: OPSW-ODFW-2012-10 Abstract -- Coast basins in Oregon support resident and anadromous cutthroat trout (Oncorhynchus clarki clarki). Cutthroat trout isolated above barriers are stream resident, but those with access to river, estuary, and marine environments may express a variety of life history and migratory patterns. Past studies (e.g. Giger 1972, Sumner 1972, Tipping 1981) indicated that estuaries serve primarily as a migratory corridor or short-term rearing environment. However, recent advances in marking and tracking technology have permitted researchers to gain a better understanding of the complex migratory and habitat use patterns of cutthroat. Krentz (2007) conducted studies in Salmon River on the central Oregon coast to explore migratory patterns of cutthroat and examine the role of the estuary as a rearing environment. Coastal cutthroat trout reared for extended periods of time throughout the available channel habitats in Salmon River estuary (Krentz 2007) during spring, summer, and fall. The estuarine resident population appeared to represent a significant portion of the migratory individuals, and included all older age classes. Estuary growth was similar to that of their ocean migrant counterparts, and survival in the estuary was high. Because cutthroat were collected and marked primarily within the estuary (Krentz 2007), it is unclear what portion of the migrant population reared in the estuary relative to the watershed or ocean, or whether the tagged group was representative of the migratory populations. The current study was designed to track a representative sample of the downstream migrant population, and assess the relative success (survival) of the estuary and ocean migrants. Similar studies in the Columbia River documented directed and rapid migration through the estuary (Zydlewski et al. 2008, Hering et al. 2009). With rare exception, cutthroat trout were not observed to rear in the estuary. In addition, many fish disappeared before reaching the ocean and few of the ocean migrants returned to the natal tributary. In this study we replicated the study design used in the Columbia River studies to further comparisons of estuary migration and rearing strategies between the two estuaries. The primary objective of our work in the Salmon River was to increase understanding of coastal cutthroat trout biology and the relationship between stream-resident and migratory, or “sea-run” cutthroat. Here we use the term “sea-run” to indicate migration into the tidally-inundated, or estuarine portions of the Salmon River watershed or to the ocean. Study objectives were to: 1.Estimate the distribution and abundance of coastal cutthroat trout in the Salmon River watershed 2.Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration 3.Describe estuary habitats used by sea-run migrants and characterize behavior within the Salmon River estuary 4.Estimate growth rate of stream and estuary resident cutthroat 5.Estimate estuary and ocean survival of sea-run individuals and document return to estuary and lower river. 6.Compare migratory behavior in Salmon River to that observed in the lower Columbia River Close