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• 21. [Article] Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics?

  Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, ...

  Citation × Citation Citation Abstract Copy Title: Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics? Author: Huber, Harriet R., Jorgensen, Jeffery C., Butler, Virginia L., Baker, Greg, Stevens, Rebecca Year: 2011 Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (O. keta), coho (O. kisutch), pink (O.gorbuscha), and sockeye salmon (O. nerka) and cutthroat (O. clarki clarki) and steelhead trout (O. mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000 to 3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A. Title: Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics? Author: Huber, Harriet R., Jorgensen, Jeffery C., Butler, Virginia L., Baker, Greg, Stevens, Rebecca Year: 2011 Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (O. keta), coho (O. kisutch), pink (O.gorbuscha), and sockeye salmon (O. nerka) and cutthroat (O. clarki clarki) and steelhead trout (O. mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000 to 3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A. Close

• 22. [Article] Evaluating "nuisance" beaver relocation as a tool to increase coho salmon habitat in the Alsea Basin of the central Oregon Coast Range

  Many stakeholders involved with stream restoration in the Pacific Northwest have discussed the potential benefits of using beaver dam construction activities (Castor canadensis) as a management tool to ...

  Citation × Citation Citation Abstract Copy Title: Evaluating "nuisance" beaver relocation as a tool to increase coho salmon habitat in the Alsea Basin of the central Oregon Coast Range Author: Petro, Vanessa M. Many stakeholders involved with stream restoration in the Pacific Northwest have discussed the potential benefits of using beaver dam construction activities (Castor canadensis) as a management tool to improve degraded stream habitat for anadromous salmon species. In addition, there has been growing interest in using nuisance beavers, primarily controlled by lethal methods, to alleviate human-wildlife conflict issues and subsequently improve Coho salmon (Oncorhynchus kisutch) rearing habitat. To understand the efficacy of using beavers as a stream restoration tool, I studied the movement, survival, and dam construction of nuisance beavers relocated to the Alsea Basin of the Oregon Coast Range. I trapped and transported 38 individuals to the nine release sites where dams constructed by beavers would benefit coho salmon productivity. All adult and sub-adult beavers were equipped with tail-mount transmitters. Beavers moved an average of 3.3 ± 0.2 (SE) stream km from release sites. The maximum distance moved from a release site was 29.2 stream km. Post-release movements did not differ significantly by age or sex. All radio-tagged individuals dispersed from their release sites. Survival 16 weeks post-release was 47%. Twelve of the radio-tagged beavers died within 90 days of release. Three cause-specific sources of mortality were identified including predation, natural causes, and human related. Mountain lions (Puma concolor) were responsible for the majority of predation based mortalities. Of the 38 nuisance beavers relocated, only five individuals contributed to the nine dams constructed post-release. Six of these dams were built by one male: female pair. All dams constructed by relocated beavers were ephemeral. In addition to monitoring post-release beaver responses, I also assessed the utility of pre-existing models to identify release site locations. Thus, I explored dam habitat relationships of extant and relocated colonies throughout the Alsea Basin. I determined the utility of locally developed spatial models was reasonable. Analysis revealed primary pool habitat and valley floor width variables as strong indicators of beaver dam sites. I conclude beaver relocation as a tool for stream restoration in the Alsea Basin may not offer an effective solution to lethal control measures and coho habitat enhancement due to low survival rates, unwanted movement and establishment outside of suitable release sites, and lack of dam construction. Title: Evaluating "nuisance" beaver relocation as a tool to increase coho salmon habitat in the Alsea Basin of the central Oregon Coast Range Author: Petro, Vanessa M. Many stakeholders involved with stream restoration in the Pacific Northwest have discussed the potential benefits of using beaver dam construction activities (Castor canadensis) as a management tool to improve degraded stream habitat for anadromous salmon species. In addition, there has been growing interest in using nuisance beavers, primarily controlled by lethal methods, to alleviate human-wildlife conflict issues and subsequently improve Coho salmon (Oncorhynchus kisutch) rearing habitat. To understand the efficacy of using beavers as a stream restoration tool, I studied the movement, survival, and dam construction of nuisance beavers relocated to the Alsea Basin of the Oregon Coast Range. I trapped and transported 38 individuals to the nine release sites where dams constructed by beavers would benefit coho salmon productivity. All adult and sub-adult beavers were equipped with tail-mount transmitters. Beavers moved an average of 3.3 ± 0.2 (SE) stream km from release sites. The maximum distance moved from a release site was 29.2 stream km. Post-release movements did not differ significantly by age or sex. All radio-tagged individuals dispersed from their release sites. Survival 16 weeks post-release was 47%. Twelve of the radio-tagged beavers died within 90 days of release. Three cause-specific sources of mortality were identified including predation, natural causes, and human related. Mountain lions (Puma concolor) were responsible for the majority of predation based mortalities. Of the 38 nuisance beavers relocated, only five individuals contributed to the nine dams constructed post-release. Six of these dams were built by one male: female pair. All dams constructed by relocated beavers were ephemeral. In addition to monitoring post-release beaver responses, I also assessed the utility of pre-existing models to identify release site locations. Thus, I explored dam habitat relationships of extant and relocated colonies throughout the Alsea Basin. I determined the utility of locally developed spatial models was reasonable. Analysis revealed primary pool habitat and valley floor width variables as strong indicators of beaver dam sites. I conclude beaver relocation as a tool for stream restoration in the Alsea Basin may not offer an effective solution to lethal control measures and coho habitat enhancement due to low survival rates, unwanted movement and establishment outside of suitable release sites, and lack of dam construction. Close

• 23. [Article] Policy Patterns across Riverscapes : Riparian Land Standards in the Oregon Coast Range

  Land management policies are ideas about nature projected onto the landscape. Culminations of social, economic, and scientific influences, these policies create standards affecting the function of ecological ...

  Citation × Citation Citation Abstract Copy Title: Policy Patterns across Riverscapes : Riparian Land Standards in the Oregon Coast Range Author: Boisjolie, Brett A. Land management policies are ideas about nature projected onto the landscape. Culminations of social, economic, and scientific influences, these policies create standards affecting the function of ecological systems. In the case of riparian lands in the Oregon Coast Range, policy requirements vary considerably across federal, state, and private land ownerships. Protective measures, such as the adoption of fixed buffer widths for maintaining vegetation, are intended to preserve natural processes important to instream habitat and water quality. However, the "policy landscape" of variable management standards can result in a fragmented approach to policy protection. This fragmentation complicates recovery efforts for threatened anadromous fish species such as coho salmon (Oncorhynchus kisutch), which require connectivity in suitable habitat segments throughout the river network. Taking a riverscape perspective, this study evaluates how aquatic protections vary across the river and its valley. To explore the patterns created from variable standard, the study first delineates categories of riparian management standards in the Oregon Coast Range. Using a geographic information system (GIS), these standards are mapped across the river networks of this region. The extent of each policy category is quantified in stream kilometers in order to evaluate policy efforts within and across the riverscapes of the Oregon Coast Range. A model of intrinsic potential for coho salmon habitat is used to identify the policy standards in stream reaches where flow, valley constraint, and channel gradient are appropriate for coho salmon habitat. A second model of the stream network (hydrography) is developed to evaluate how differences in stream delineation can influence policy patterns. Results indicate that riparian lands of the Oregon Coast Range are protected by variable standards for land management, including buffer widths that range from 0 to ~152m. In streams important to coho salmon, a lower proportion of the stream network was found to be protected by policy standards compared to the watershed and ESU scale. A lack of stream data central to policy application (fish use, stream flow duration, mean annual flow, water use) complicated our ability to attribute stream segments with specific land management requirements. The choice of hydrographic data was also found to influence the proportional extent of policies within riverscapes. This framework for assessing the spatial distribution of policies can provide insights for future studies of riverscape systems. Title: Policy Patterns across Riverscapes : Riparian Land Standards in the Oregon Coast Range Author: Boisjolie, Brett A. Land management policies are ideas about nature projected onto the landscape. Culminations of social, economic, and scientific influences, these policies create standards affecting the function of ecological systems. In the case of riparian lands in the Oregon Coast Range, policy requirements vary considerably across federal, state, and private land ownerships. Protective measures, such as the adoption of fixed buffer widths for maintaining vegetation, are intended to preserve natural processes important to instream habitat and water quality. However, the "policy landscape" of variable management standards can result in a fragmented approach to policy protection. This fragmentation complicates recovery efforts for threatened anadromous fish species such as coho salmon (Oncorhynchus kisutch), which require connectivity in suitable habitat segments throughout the river network. Taking a riverscape perspective, this study evaluates how aquatic protections vary across the river and its valley. To explore the patterns created from variable standard, the study first delineates categories of riparian management standards in the Oregon Coast Range. Using a geographic information system (GIS), these standards are mapped across the river networks of this region. The extent of each policy category is quantified in stream kilometers in order to evaluate policy efforts within and across the riverscapes of the Oregon Coast Range. A model of intrinsic potential for coho salmon habitat is used to identify the policy standards in stream reaches where flow, valley constraint, and channel gradient are appropriate for coho salmon habitat. A second model of the stream network (hydrography) is developed to evaluate how differences in stream delineation can influence policy patterns. Results indicate that riparian lands of the Oregon Coast Range are protected by variable standards for land management, including buffer widths that range from 0 to ~152m. In streams important to coho salmon, a lower proportion of the stream network was found to be protected by policy standards compared to the watershed and ESU scale. A lack of stream data central to policy application (fish use, stream flow duration, mean annual flow, water use) complicated our ability to attribute stream segments with specific land management requirements. The choice of hydrographic data was also found to influence the proportional extent of policies within riverscapes. This framework for assessing the spatial distribution of policies can provide insights for future studies of riverscape systems. Close

• 24. [Article] Fish Use of the Estuary: 1999 Tillamook Bay Monitoring Report

  Abstract -- The study was conducted during the summer and autumn of 1998 and the spring and summer of 1999. The fish sampling done in 1998 was used to provide an estuary-wide overview of the fish species ...

  Citation × Citation Citation Abstract Copy Title: Fish Use of the Estuary: 1999 Tillamook Bay Monitoring Report Abstract -- The study was conducted during the summer and autumn of 1998 and the spring and summer of 1999. The fish sampling done in 1998 was used to provide an estuary-wide overview of the fish species composition and relative abundance during the mid-summer period and to test sampling gear and sampling strategies for development of a long-term monitoring program. The sampling conducted in 1999 built upon the information gained in 1998 and provided an initial test of a sampling design for long-term monitoring of the Bay's fish community. Sampling of the fish community in 1998 was conducted using beach seine, bottom trawl, fyke net and round-haul net. During 1999, initial testing of the proposed long-term monitoring program was conducted using beach seine, trawl and fyke nets. A total of 40 fish species were collected during this study whereas a total of 59 species were captured during ODFW's surveys during the mid- 1970s. Of the 40 species captured in this study, all but four were present in the mid- 1970s. Eight of the ten most abundant species present in the mid-1970s were among the ten most abundant species captured in this study. All but one of the abundant species in the beach seine catch were found throughout the estuary. All five species of anadromous salmonids known to occur in the Tillamook Bay watershed were collected during this study. However, only juvenile chum and chinook salmon were caught in any abundance. The most abundant non-salmonid species in the estuary were euryhaline marine species. Title: Fish Use of the Estuary: 1999 Tillamook Bay Monitoring Report Abstract -- The study was conducted during the summer and autumn of 1998 and the spring and summer of 1999. The fish sampling done in 1998 was used to provide an estuary-wide overview of the fish species composition and relative abundance during the mid-summer period and to test sampling gear and sampling strategies for development of a long-term monitoring program. The sampling conducted in 1999 built upon the information gained in 1998 and provided an initial test of a sampling design for long-term monitoring of the Bay's fish community. Sampling of the fish community in 1998 was conducted using beach seine, bottom trawl, fyke net and round-haul net. During 1999, initial testing of the proposed long-term monitoring program was conducted using beach seine, trawl and fyke nets. A total of 40 fish species were collected during this study whereas a total of 59 species were captured during ODFW's surveys during the mid- 1970s. Of the 40 species captured in this study, all but four were present in the mid- 1970s. Eight of the ten most abundant species present in the mid-1970s were among the ten most abundant species captured in this study. All but one of the abundant species in the beach seine catch were found throughout the estuary. All five species of anadromous salmonids known to occur in the Tillamook Bay watershed were collected during this study. However, only juvenile chum and chinook salmon were caught in any abundance. The most abundant non-salmonid species in the estuary were euryhaline marine species. Close

• 25. [Article] Indian Creek Aquatic Restoration (OWEB #205-144)

  Abstract -- Like many streams in this area, these creeks have experienced considerable habitat degradation due to past land management practices that removed large wood from the channels. Without the large ...

  Citation × Citation Citation Abstract Copy Title: Indian Creek Aquatic Restoration (OWEB #205-144) Abstract -- Like many streams in this area, these creeks have experienced considerable habitat degradation due to past land management practices that removed large wood from the channels. Without the large wood, spawning gravels have washed away leaving a mostly bedrock substrate. The down-cut stream is no longer connected to its former floodplain and fish have little refuge during high flows. Additionally, aquatic insect life, the basic food source for young salmonids, is limited without the diverse habitats formed by complexes of wood and gravel. Goals associated with this restoration proposal include: • Address limitation to anadromous fish production in Indian Creek tributaries o Enhance spawning, rearing, and overwintering habitat for anadromous and resident fish species o Restore storage capacity (water, substrates, and detritus) of the selected streams to levels more closely expected with unaltered systems in the Coast Range. • Establish a connection between past small scale restoration efforts • Maintain a network of organizations, stakeholders, and individuals who will participate in watershed restoration efforts. Widened channel floodplain from newly derived gravel, side channel formation / channel alteration (with more sinuosity), and additional scour pools were observed throughout the structure sites we monitored since the project implementation from high water events. Especially, the amount of gravel that was delivered to the project reaches and the degree to which they were sorted in large concentration directly adjacent to the helicopter structures was far more prominent than what we have observed in previous years from other helicopter projects. Title: Indian Creek Aquatic Restoration (OWEB #205-144) Abstract -- Like many streams in this area, these creeks have experienced considerable habitat degradation due to past land management practices that removed large wood from the channels. Without the large wood, spawning gravels have washed away leaving a mostly bedrock substrate. The down-cut stream is no longer connected to its former floodplain and fish have little refuge during high flows. Additionally, aquatic insect life, the basic food source for young salmonids, is limited without the diverse habitats formed by complexes of wood and gravel. Goals associated with this restoration proposal include: • Address limitation to anadromous fish production in Indian Creek tributaries o Enhance spawning, rearing, and overwintering habitat for anadromous and resident fish species o Restore storage capacity (water, substrates, and detritus) of the selected streams to levels more closely expected with unaltered systems in the Coast Range. • Establish a connection between past small scale restoration efforts • Maintain a network of organizations, stakeholders, and individuals who will participate in watershed restoration efforts. Widened channel floodplain from newly derived gravel, side channel formation / channel alteration (with more sinuosity), and additional scour pools were observed throughout the structure sites we monitored since the project implementation from high water events. Especially, the amount of gravel that was delivered to the project reaches and the degree to which they were sorted in large concentration directly adjacent to the helicopter structures was far more prominent than what we have observed in previous years from other helicopter projects. Close

• 26. [Article] The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss

  The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation ...

  Citation × Citation Citation Abstract Copy Title: The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss Author: Ohms, Haley The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation of partially migratory species. In particular, why individuals adopt a particular phenotype has been the focus of numerous research efforts. In the partially migratory species Oncorhynchys mykiss (commonly known as steelhead and rainbow trout), I found that sex plays a strong role in whether an individual adopts an anadromous or resident life history. I observed a higher frequency of females adopting the anadromous tactic throughout the species range, and I attributed this to the relationship between body size and reproductive success in females that is not present in males. I did not observe differences in female bias along gradients of latitude or migration distance, and I hypothesize that while the frequency of tactics among populations may change along these gradients, either the change is equal between males and females, or an interaction of latitude and migration distance may control changes. I did not observe a corresponding male bias in the one resident population I sampled, and suggest that this is the result of a high frequency of residents in that population. I propose that sex ratios could be a valuable metric for measuring frequency of life-history tactics in populations and could facilitate the investigation into the controls of life-history tactics across broad scales. Title: The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss Author: Ohms, Haley The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation of partially migratory species. In particular, why individuals adopt a particular phenotype has been the focus of numerous research efforts. In the partially migratory species Oncorhynchys mykiss (commonly known as steelhead and rainbow trout), I found that sex plays a strong role in whether an individual adopts an anadromous or resident life history. I observed a higher frequency of females adopting the anadromous tactic throughout the species range, and I attributed this to the relationship between body size and reproductive success in females that is not present in males. I did not observe differences in female bias along gradients of latitude or migration distance, and I hypothesize that while the frequency of tactics among populations may change along these gradients, either the change is equal between males and females, or an interaction of latitude and migration distance may control changes. I did not observe a corresponding male bias in the one resident population I sampled, and suggest that this is the result of a high frequency of residents in that population. I propose that sex ratios could be a valuable metric for measuring frequency of life-history tactics in populations and could facilitate the investigation into the controls of life-history tactics across broad scales. Close

• 27. [Article] The Umpqua River study : a joint report

  The species of anadromous fish entering the Umpqua River are: chinook salmon (spring, summer, and fall runs), silver salmon, steelhead trout (summer and winter runs), cutthroat trout, shad, striped bass ...

  Citation × Citation Citation Abstract Copy Title: The Umpqua River study : a joint report Author: Oregon. State Game Commission, Oregon. Fish Commission The species of anadromous fish entering the Umpqua River are: chinook salmon (spring, summer, and fall runs), silver salmon, steelhead trout (summer and winter runs), cutthroat trout, shad, striped bass and sturgeon. The winter steelhead, striped bass, and shad runs appear to be maintaining themselves. The runs of the other species appear to be in various stages of depletion. Major factors which have contributed to this depletion are: overfishing by the commercial fishery and more recently the sport fishery; and barriers such as log jams, "splash" damns, mill dam and hydroelectric developments. Other factors which may be of importance are: predation; unscreened gravity water diversions; water removal by pumping for irrigation, industrial, and municipal use; and fluctuations in water levels due to meterological conditions. The total run of spring chinook salmon into the Umpqua River in 1946 was estimated to be 4,400 fish of which approximately 935 were jacks. (fish under 20 inches). The fishing mortality of shad of commercial size, in the 1946 Umpqua River run, was estimated to be 50 percent. The total catch of the various species of salmon by the commercial and sport fisheries in 1946 were as follows: Under a proper management program, an average sustained yield of several times in the 1946 catches may be expected. During 1946, anglers spent at least $292,700 in this area while fishing for salmon and trout in the Umpqua River. The capital investment was estimated to be $2,402,500. The commercial fishery products of salmon steelhead, shad, striped bass, pilchards, and crabs taken from the Umpqua River in 1946 had a wholesale valur of $652,400. The capital investment was not determined. Title: The Umpqua River study : a joint report Author: Oregon. State Game Commission, Oregon. Fish Commission The species of anadromous fish entering the Umpqua River are: chinook salmon (spring, summer, and fall runs), silver salmon, steelhead trout (summer and winter runs), cutthroat trout, shad, striped bass and sturgeon. The winter steelhead, striped bass, and shad runs appear to be maintaining themselves. The runs of the other species appear to be in various stages of depletion. Major factors which have contributed to this depletion are: overfishing by the commercial fishery and more recently the sport fishery; and barriers such as log jams, "splash" damns, mill dam and hydroelectric developments. Other factors which may be of importance are: predation; unscreened gravity water diversions; water removal by pumping for irrigation, industrial, and municipal use; and fluctuations in water levels due to meterological conditions. The total run of spring chinook salmon into the Umpqua River in 1946 was estimated to be 4,400 fish of which approximately 935 were jacks. (fish under 20 inches). The fishing mortality of shad of commercial size, in the 1946 Umpqua River run, was estimated to be 50 percent. The total catch of the various species of salmon by the commercial and sport fisheries in 1946 were as follows: Under a proper management program, an average sustained yield of several times in the 1946 catches may be expected. During 1946, anglers spent at least $292,700 in this area while fishing for salmon and trout in the Umpqua River. The capital investment was estimated to be $2,402,500. The commercial fishery products of salmon steelhead, shad, striped bass, pilchards, and crabs taken from the Umpqua River in 1946 had a wholesale valur of $652,400. The capital investment was not determined. Close

• 28. [Article] Aspects of the early life history of juvenile salmonids in the Dungeness River Estuary

  The decline of many Pacific salmon stocks has stimulated interest in the early life history and habitat requirements of juvenile salmon. Although estuarine habitat associations of juvenile salmon have ...

  Citation × Citation Citation Abstract Copy Title: Aspects of the early life history of juvenile salmonids in the Dungeness River Estuary Author: Sather, Nichole K. The decline of many Pacific salmon stocks has stimulated interest in the early life history and habitat requirements of juvenile salmon. Although estuarine habitat associations of juvenile salmon have been investigated in many coastal areas of the eastern Pacific Ocean, until recently, little was known about juvenile salmonid ecology within the Straits of Juan de Fuca. During the Spring/Summer outmigration period in 2006 and 2007, I examined the early life history of the five species of anadromous salmon in the Dungeness River estuary on the north Olympic Peninsula, Washington. I sampled multiple spatial scales within several habitat types to characterize salmon distribution and habitat use. My results presented in this thesis are segregated into two components: 1) tidal marsh ecology of juvenile salmonids in the Dungeness River estuary, and 2) the landscape-scale distribution of juvenile salmonids within the Dungeness River estuary. I examined the population of juvenile salmonids within blind tidal sloughs near the vicinity of the Dungeness River delta. Salmonids were present within the tidal marshes throughout the entire outmigration period (e.g., March through July). Juvenile Chinook salmon (Oncorhynchus tshawytscha) were the most abundant salmonid species within the marshes. Based on the temporal distribution and size structure of juvenile Chinook salmon in the estuary I identified at least four life history types: 1) a fry strategy included a large pulse of fish emigrating from the river at a small size (e.g., 35-45mm FL) during late winter and early spring months; 2) the second group of fish was the least abundant group emigrating from the river from April through mid May at sizes ranging from 50-75mm FL; 3) the third group of migrants entered the estuary between from late spring through the summer months at larger sizes than the initial groups (e.g., 60-90mm FL); and 4) the final group of Chinook salmon included a stream-type yearling strategy. In addition to the four life history strategies identified for Chinook salmon, I detected at least three groups of chum salmon migrating into the estuary. These groups were distinguished by their size and timing of migration and are further described according to different rearing strategies. The distribution of juvenile salmonids was most strongly influenced by the degree of connectivity (i.e., distance) between the tidal marshes and the mouth of the Dungeness River. Habitat complexity and opportunity also governed the distribution of juvenile salmonids within the tidal marshes. I also sampled three regions of the estuary with a beach seine to investigate the nearshore distribution of juvenile salmonids within the Dungeness River estuary: the delta face, inner Bay, and outer Bay. Among the three regions, species composition was highly variable between 2006 and 2007. The most common salmonids encountered within the beach seine sites included Chinook salmon, chum salmon (O. kisutch), and pink salmon (O. gorbuscha). The relative abundance of salmonids was highest near the delta face and lowest within the outer bay area. The landscape-scale distribution and habitat use of juvenile salmonids within the Dungeness River estuary is largely influenced by ecosystem connectivity, but is also linked to biotic characteristics of the fish (e.g., life history type and fish size). Although the Dungeness includes hydrogeomorphic characteristics (e.g., steep river gradient, composition of sand spits in the estuary) unique to other Pacific Northwest watersheds, this system produces a variety of life history types comparable to other estuaries. Understanding the mechanisms that drive the distribution of juvenile salmonids within the Dungeness will supply local resource managers with a baseline with which to establish ecosystem restoration goals. Title: Aspects of the early life history of juvenile salmonids in the Dungeness River Estuary Author: Sather, Nichole K. The decline of many Pacific salmon stocks has stimulated interest in the early life history and habitat requirements of juvenile salmon. Although estuarine habitat associations of juvenile salmon have been investigated in many coastal areas of the eastern Pacific Ocean, until recently, little was known about juvenile salmonid ecology within the Straits of Juan de Fuca. During the Spring/Summer outmigration period in 2006 and 2007, I examined the early life history of the five species of anadromous salmon in the Dungeness River estuary on the north Olympic Peninsula, Washington. I sampled multiple spatial scales within several habitat types to characterize salmon distribution and habitat use. My results presented in this thesis are segregated into two components: 1) tidal marsh ecology of juvenile salmonids in the Dungeness River estuary, and 2) the landscape-scale distribution of juvenile salmonids within the Dungeness River estuary. I examined the population of juvenile salmonids within blind tidal sloughs near the vicinity of the Dungeness River delta. Salmonids were present within the tidal marshes throughout the entire outmigration period (e.g., March through July). Juvenile Chinook salmon (Oncorhynchus tshawytscha) were the most abundant salmonid species within the marshes. Based on the temporal distribution and size structure of juvenile Chinook salmon in the estuary I identified at least four life history types: 1) a fry strategy included a large pulse of fish emigrating from the river at a small size (e.g., 35-45mm FL) during late winter and early spring months; 2) the second group of fish was the least abundant group emigrating from the river from April through mid May at sizes ranging from 50-75mm FL; 3) the third group of migrants entered the estuary between from late spring through the summer months at larger sizes than the initial groups (e.g., 60-90mm FL); and 4) the final group of Chinook salmon included a stream-type yearling strategy. In addition to the four life history strategies identified for Chinook salmon, I detected at least three groups of chum salmon migrating into the estuary. These groups were distinguished by their size and timing of migration and are further described according to different rearing strategies. The distribution of juvenile salmonids was most strongly influenced by the degree of connectivity (i.e., distance) between the tidal marshes and the mouth of the Dungeness River. Habitat complexity and opportunity also governed the distribution of juvenile salmonids within the tidal marshes. I also sampled three regions of the estuary with a beach seine to investigate the nearshore distribution of juvenile salmonids within the Dungeness River estuary: the delta face, inner Bay, and outer Bay. Among the three regions, species composition was highly variable between 2006 and 2007. The most common salmonids encountered within the beach seine sites included Chinook salmon, chum salmon (O. kisutch), and pink salmon (O. gorbuscha). The relative abundance of salmonids was highest near the delta face and lowest within the outer bay area. The landscape-scale distribution and habitat use of juvenile salmonids within the Dungeness River estuary is largely influenced by ecosystem connectivity, but is also linked to biotic characteristics of the fish (e.g., life history type and fish size). Although the Dungeness includes hydrogeomorphic characteristics (e.g., steep river gradient, composition of sand spits in the estuary) unique to other Pacific Northwest watersheds, this system produces a variety of life history types comparable to other estuaries. Understanding the mechanisms that drive the distribution of juvenile salmonids within the Dungeness will supply local resource managers with a baseline with which to establish ecosystem restoration goals. Close

• 29. [Article] The future of the Columbia River salmon fisheries

  The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources ...

  Citation × Citation Citation Abstract Copy Title: The future of the Columbia River salmon fisheries Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources for their livelihood; and their welfare is dependent upon the maintenance of the salmon runs. It is to the special interest of these people that the salmon supply be maintained at the level of maximum productivity and, indirectly, it is to the interest of all the citizens of these states that this be done. In recent years it has become increasingly evident that these resources, taken as. a whole, are decreasing in productivity and it has been frequently pointed out that this decrease is due primarily to the operation of two factors-- a very intensive fishery and a reduction in spawning and rearing areas due to the utilization of the water resources of the Columbia basin for other purposes. These influences, however, have affected the several species of salmon that are found in the Columbia River quite differently; the more valuable species, Chinooks and bluebacks, showing more evidence of depletion than do the other species, silver salmon, chums and steelhead. Title: The future of the Columbia River salmon fisheries Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources for their livelihood; and their welfare is dependent upon the maintenance of the salmon runs. It is to the special interest of these people that the salmon supply be maintained at the level of maximum productivity and, indirectly, it is to the interest of all the citizens of these states that this be done. In recent years it has become increasingly evident that these resources, taken as. a whole, are decreasing in productivity and it has been frequently pointed out that this decrease is due primarily to the operation of two factors-- a very intensive fishery and a reduction in spawning and rearing areas due to the utilization of the water resources of the Columbia basin for other purposes. These influences, however, have affected the several species of salmon that are found in the Columbia River quite differently; the more valuable species, Chinooks and bluebacks, showing more evidence of depletion than do the other species, silver salmon, chums and steelhead. Close

• 30. [Article] Fish Inves 1947 pt 1.pdf

  Citation × Citation Citation Abstract Copy Title: Fish Inves 1947 pt 1.pdf Author: Oregon. State Game Commission Title: Fish Inves 1947 pt 1.pdf Author: Oregon. State Game Commission Close