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• 31. [Article] Oregon coastal salmon and steelhead tagging programs

  Part I. To aid in the management of the Tillamook Bay commercial salmon fishery, a tagging program was conducted on the salmon and steelhead trout runs in 1953. General migration behavior, the minimum ...

  Citation × Citation Citation Abstract Copy Title: Oregon coastal salmon and steelhead tagging programs Author: Henry, Kenneth A., Morgan, Alfred R. Part I. To aid in the management of the Tillamook Bay commercial salmon fishery, a tagging program was conducted on the salmon and steelhead trout runs in 1953. General migration behavior, the minimum length of time the fish remained in the fishery, population sizes, and fishing mortalities were determined from this study. Part II. To aid in the management of the Siletz River commercial salmon fishery, a tagging program was conducted on the salmon and steelhead trout runs in 1954. General migration behavior, the minimum length of time fish remained in the fishery, population estimates, and fishing mortalities were determined. Title: Oregon coastal salmon and steelhead tagging programs Author: Henry, Kenneth A., Morgan, Alfred R. Part I. To aid in the management of the Tillamook Bay commercial salmon fishery, a tagging program was conducted on the salmon and steelhead trout runs in 1953. General migration behavior, the minimum length of time the fish remained in the fishery, population sizes, and fishing mortalities were determined from this study. Part II. To aid in the management of the Siletz River commercial salmon fishery, a tagging program was conducted on the salmon and steelhead trout runs in 1954. General migration behavior, the minimum length of time fish remained in the fishery, population estimates, and fishing mortalities were determined. Close

• 32. [Article] Geospatial depiction of fall run Chinook Salmon in Wallowa County

  This product is for informational purposes and may not have been prepared for, or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary ...

  Citation × Citation Citation Abstract Copy Title: Geospatial depiction of fall run Chinook Salmon in Wallowa County Author: Thomas, Samuel, Department of Fish and Wildlife, State of Oregon, Oregon State University This product is for informational purposes and may not have been prepared for, or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to verify the purpose and limitations. The data is provided as-is, without warranty. Title: Geospatial depiction of fall run Chinook Salmon in Wallowa County Author: Thomas, Samuel, Department of Fish and Wildlife, State of Oregon, Oregon State University This product is for informational purposes and may not have been prepared for, or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to verify the purpose and limitations. The data is provided as-is, without warranty. Close

• 33. [Article] Factors affecting the abundance of fall chinook salmon in the Columbia River

  A study of the population ecology of Columbia River fall chinook salmon, Oncorhynchus tshawytscha (Walbaum), was made in an attempt to determine the cause of a serious decline in this run which occurred in ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting the abundance of fall chinook salmon in the Columbia River Author: Van Hyning, Jack M. A study of the population ecology of Columbia River fall chinook salmon, Oncorhynchus tshawytscha (Walbaum), was made in an attempt to determine the cause of a serious decline in this run which occurred in the early 1950's. Fluctuations in abundance of major salmon runs the North Pacific were examined to detect any coastwide pattern. Only chinook salmon in Cook Inlet, Alaska, and chum salmon from Oregon to southwestern Alaska showed a similar trend. The following life history stages broken down into pre- and post-decline years were examined: (1) marine life including distribution and migration, growth and maturity, survival rate, oceanography, and commercial and sport fisheries; (2) upstream migration including river fisheries, gear selectivity, size and age composition of the run, escapement, and influence of dams, diseases, and water quality; (3) reproduction and incubation including spawning areas and spawning and incubation conditions; and (4) downstream migration which included predation, dams and reservoirs, diseases, flow, turbidity and temperature, and estuary life. Salient points of the analysis were: (1) a change in the maturity and survival pattern based on tagged and fin-clipped fish recovered before and after 1950; (2) a significant negative correlation between sea-water temperature during a year class' first year at sea and subsequent survival; (3) a large increase in the ocean fisheries coincident with the decline in the run; (4) catch-effort statistics of the ocean fishery show a near classic example of the effect of overexploitation; (5) estimates of the contribution of Columbia River chinook to the ocean fisheries based on tag recoveries could be underestimates rather than overestimates; (6) a significant inverse correlation between estimated ocean catch of Columbia River fall chinook and numbers entering the river; (7) size and age composition of the ocean and river catches decreased coincident with the decline in the run; (8) the gill-net fishery shows little size selectivity by age, size, or sex in the dominant group; (9) fluctuations in abundance of hatchery stocks are related to differences in survival between fingerling and adult; (10) hatchery, lower river, and upriver populations fluctuate in abundance in much the same pattern; (11) optimum escapement is between 90,000 and 100,000 adults, a value that was exceeded during most years; (12) a highly significant negative correlation between numbers of spawners and return per spawner; (13) most of the early dams had no direct effect on fall chinook and the decline in productivity occurred when river conditions were relatively stable; (14) temperatures at time of migration and spawning for fall chinook have not increased enough to be a serious mortality factor; (15) little relationship between flow, turbidity, and temperature at time of downstream migration and subsequent return was evident except that high temperatures and high flows (and turbidities) tended to produce poorer runs during certain time periods; and (16) predation and delay of smolts in reservoirs are largely unknown factors, but circumstantial evidence suggests that they were not important in regulating fall chinook numbers during the period of the study. Finally, variables that appeared to bear some relationship to fluctuations in abundance of fall chinook were submitted to multiple regression analysis. For the predecline period (1938-46 brood years), sea-water temperature and ocean troll fishing effort were significant variables (R² = 0.74). For post decline years (1947-59 broods), troll had the most influence on total return with ocean temperature and escapement having lesser effects. For the combined years, troll intensity and ocean temperature were the significant variables (R² = 0.572). Entering interaction of river flow at downstream migration with the other variables brought R² to 0.754 which means that 75% of the variability in the returning run could be accounted for by these three factors. Return per spawner was so heavily influenced by numbers of spawners that the other factors assumed negligible importance. Equations were derived that predicted the returning run in close agreement with the actual run size. Substituting a low and constant troll fishing effort in the equation resulted in the predicted run maintaining the average predecline level. The increase in ocean fishing was the main contributor to the decline of the Columbia River fall chinook run as shown by correlation, by analogy, and by the process of elimination. To demonstrate why other chinook runs have not shown similar declines, it was shown that due to several unique features in Columbia River fall chinook life history they are exposed to much more ocean fishing than other populations. It was emphasized that these conclusions should not be extrapolated to the future or to other species or runs of salmon. Title: Factors affecting the abundance of fall chinook salmon in the Columbia River Author: Van Hyning, Jack M. A study of the population ecology of Columbia River fall chinook salmon, Oncorhynchus tshawytscha (Walbaum), was made in an attempt to determine the cause of a serious decline in this run which occurred in the early 1950's. Fluctuations in abundance of major salmon runs the North Pacific were examined to detect any coastwide pattern. Only chinook salmon in Cook Inlet, Alaska, and chum salmon from Oregon to southwestern Alaska showed a similar trend. The following life history stages broken down into pre- and post-decline years were examined: (1) marine life including distribution and migration, growth and maturity, survival rate, oceanography, and commercial and sport fisheries; (2) upstream migration including river fisheries, gear selectivity, size and age composition of the run, escapement, and influence of dams, diseases, and water quality; (3) reproduction and incubation including spawning areas and spawning and incubation conditions; and (4) downstream migration which included predation, dams and reservoirs, diseases, flow, turbidity and temperature, and estuary life. Salient points of the analysis were: (1) a change in the maturity and survival pattern based on tagged and fin-clipped fish recovered before and after 1950; (2) a significant negative correlation between sea-water temperature during a year class' first year at sea and subsequent survival; (3) a large increase in the ocean fisheries coincident with the decline in the run; (4) catch-effort statistics of the ocean fishery show a near classic example of the effect of overexploitation; (5) estimates of the contribution of Columbia River chinook to the ocean fisheries based on tag recoveries could be underestimates rather than overestimates; (6) a significant inverse correlation between estimated ocean catch of Columbia River fall chinook and numbers entering the river; (7) size and age composition of the ocean and river catches decreased coincident with the decline in the run; (8) the gill-net fishery shows little size selectivity by age, size, or sex in the dominant group; (9) fluctuations in abundance of hatchery stocks are related to differences in survival between fingerling and adult; (10) hatchery, lower river, and upriver populations fluctuate in abundance in much the same pattern; (11) optimum escapement is between 90,000 and 100,000 adults, a value that was exceeded during most years; (12) a highly significant negative correlation between numbers of spawners and return per spawner; (13) most of the early dams had no direct effect on fall chinook and the decline in productivity occurred when river conditions were relatively stable; (14) temperatures at time of migration and spawning for fall chinook have not increased enough to be a serious mortality factor; (15) little relationship between flow, turbidity, and temperature at time of downstream migration and subsequent return was evident except that high temperatures and high flows (and turbidities) tended to produce poorer runs during certain time periods; and (16) predation and delay of smolts in reservoirs are largely unknown factors, but circumstantial evidence suggests that they were not important in regulating fall chinook numbers during the period of the study. Finally, variables that appeared to bear some relationship to fluctuations in abundance of fall chinook were submitted to multiple regression analysis. For the predecline period (1938-46 brood years), sea-water temperature and ocean troll fishing effort were significant variables (R² = 0.74). For post decline years (1947-59 broods), troll had the most influence on total return with ocean temperature and escapement having lesser effects. For the combined years, troll intensity and ocean temperature were the significant variables (R² = 0.572). Entering interaction of river flow at downstream migration with the other variables brought R² to 0.754 which means that 75% of the variability in the returning run could be accounted for by these three factors. Return per spawner was so heavily influenced by numbers of spawners that the other factors assumed negligible importance. Equations were derived that predicted the returning run in close agreement with the actual run size. Substituting a low and constant troll fishing effort in the equation resulted in the predicted run maintaining the average predecline level. The increase in ocean fishing was the main contributor to the decline of the Columbia River fall chinook run as shown by correlation, by analogy, and by the process of elimination. To demonstrate why other chinook runs have not shown similar declines, it was shown that due to several unique features in Columbia River fall chinook life history they are exposed to much more ocean fishing than other populations. It was emphasized that these conclusions should not be extrapolated to the future or to other species or runs of salmon. Close

• 34. [Article] Potential Effects of Management on Caspian Tern Hydroprogne caspia Predation on Juvenile Salmonids at a Colony in San Francisco Bay, California

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is published by Taylor & ...

  Citation × Citation Citation Abstract Copy Title: Potential Effects of Management on Caspian Tern Hydroprogne caspia Predation on Juvenile Salmonids at a Colony in San Francisco Bay, California Author: Evans, Allen F., Adrean, Lindsay J., Roby, Daniel D., Lyons, Donald E., Collis, Ken To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is published by Taylor & Francis and can be found at: http://www.taylorandfrancis.com. Copyrighted by American Fisheries Society (http://afsjournals.org/). Title: Potential Effects of Management on Caspian Tern Hydroprogne caspia Predation on Juvenile Salmonids at a Colony in San Francisco Bay, California Author: Evans, Allen F., Adrean, Lindsay J., Roby, Daniel D., Lyons, Donald E., Collis, Ken To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is published by Taylor & Francis and can be found at: http://www.taylorandfrancis.com. Copyrighted by American Fisheries Society (http://afsjournals.org/). Close

• 35. [Article] Caspian tern (Hydroprogne caspia) foraging ecology and predation on juvenile salmonids in San Francisco Bay, California

  Brooks Island, located in central San Francisco Bay, California, currently supports the largest breeding colony of Caspian terns (Hydroprogne caspia) in the Bay Area, and is one of several proposed relocation ...

  Citation × Citation Citation Abstract Copy Title: Caspian tern (Hydroprogne caspia) foraging ecology and predation on juvenile salmonids in San Francisco Bay, California Author: Adrean, Lindsay J. Brooks Island, located in central San Francisco Bay, California, currently supports the largest breeding colony of Caspian terns (Hydroprogne caspia) in the Bay Area, and is one of several proposed relocation sites for some Caspian terns from the world's largest colony in the Columbia River estuary of Oregon. Juvenile salmonids have been identified in the diet of Caspian terns nesting at Brooks Island, so I investigated whether the colony, at its current or an enhanced size, poses a threat to the recovery of several runs of salmonids (Oncorhynchus spp.) in San Francisco Bay that are listed under the U.S. Endangered Species Act (ESA). I also examined the foraging ecology of Brooks Island Caspian terns to 1) determine whether the colony is suitable for expansion based on availability of forage fish resources, a factor potentially limiting the size and productivity of the colony, and 2) investigate how Caspian terns nesting at this colony exploit forage fish resources. I used a bioenergetics modeling approach, employing estimates of tern energy requirements and proportions of energy supplied by various prey types, to estimate consumption of juvenile salmonids by Caspian terns nesting on Brooks Island during 2008 and 2009. Estimated salmonid consumption was 205,000 smolts (95% CI: 175,000 – 245,000 smolts) in 2008 and 167,000 smolts (95% CI: 144,000 – 191,000 smolts) in 2009. Predation rates on ESA-listed Central Valley spring-run Chinook salmon (O. tshawytscha; 0.08%) were lower than those on unlisted fall-run Chinook salmon (1.0%). Average per capita predation rates on juvenile salmonids by Brooks Island Caspian terns (2008: 126 fish; 2009: 123 fish) were less than half those of Caspian terns nesting in the Columbia River estuary. If the current downward trend in the number of Caspian terns nesting on Brooks Island continues until the colony is no longer extant, the resulting declines in predation on salmonids would lead to increases in annual population growth rates (Δλ) of salmonid runs of just small fractions of one percentage point. The proposed enhancement of the Brooks Island Caspian tern colony to 3,000 individuals would at most cause declines in annual population growth rates of 0.3% for fall-run Chinook salmon and 0.02% for threatened spring-run Chinook salmon, assuming that smolt mortality from tern predation is 100% additive. This level of impact to the ESA-listed spring-run Chinook salmon stock is less than the level considered acceptable by the National Marine Fisheries Service (Δλ = 0.05%). Radio-tracking of Caspian terns nesting on Brooks Island revealed that the maximum foraging distance from the colony was 80 km. The median foraging distance from the colony was greater in 2009 compared to 2008 (20.6 km vs. 14.0 km), average number of foraging trips per day was higher (4.4 vs. 3.4 foraging trips), and average adult colony attendance was lower (43% vs. 52% of daylight hours). These results indicate that the colony was more food-limited during the 2009 breeding season, concurrent with anomalous downwelling along the coast of northern California and reduced availability and size of marine forage fishes, such as herring, sardines, and anchovies. Caspian terns used a number of core foraging areas within 30 km of the Brooks Island colony, both inside and just outside the Bay. Two large core foraging areas were close to or overlapped with the release site for juvenile salmonids in eastern San Pablo Bay, where > 10 million hatchery-raised smolts were released from net pens during both the 2008 and 2009 tern nesting seasons. This finding supports the hypothesis that most juvenile salmonids consumed by terns nesting at the Brooks Island colony were captured at or near the release site. Individual Caspian terns displayed foraging site fidelity, suggesting that foraging at the release site for hatchery-raised salmonids was a learned behavior by some terns. The Brooks Island colony site is within foraging distance of adequate marine forage fish resources in most years, and Caspian terns nesting there are not dependent on juvenile salmonids as a food resource. Consumption of juvenile salmonids by Brooks Island terns would be largely curtailed by modification of hatchery release practices. Title: Caspian tern (Hydroprogne caspia) foraging ecology and predation on juvenile salmonids in San Francisco Bay, California Author: Adrean, Lindsay J. Brooks Island, located in central San Francisco Bay, California, currently supports the largest breeding colony of Caspian terns (Hydroprogne caspia) in the Bay Area, and is one of several proposed relocation sites for some Caspian terns from the world's largest colony in the Columbia River estuary of Oregon. Juvenile salmonids have been identified in the diet of Caspian terns nesting at Brooks Island, so I investigated whether the colony, at its current or an enhanced size, poses a threat to the recovery of several runs of salmonids (Oncorhynchus spp.) in San Francisco Bay that are listed under the U.S. Endangered Species Act (ESA). I also examined the foraging ecology of Brooks Island Caspian terns to 1) determine whether the colony is suitable for expansion based on availability of forage fish resources, a factor potentially limiting the size and productivity of the colony, and 2) investigate how Caspian terns nesting at this colony exploit forage fish resources. I used a bioenergetics modeling approach, employing estimates of tern energy requirements and proportions of energy supplied by various prey types, to estimate consumption of juvenile salmonids by Caspian terns nesting on Brooks Island during 2008 and 2009. Estimated salmonid consumption was 205,000 smolts (95% CI: 175,000 – 245,000 smolts) in 2008 and 167,000 smolts (95% CI: 144,000 – 191,000 smolts) in 2009. Predation rates on ESA-listed Central Valley spring-run Chinook salmon (O. tshawytscha; 0.08%) were lower than those on unlisted fall-run Chinook salmon (1.0%). Average per capita predation rates on juvenile salmonids by Brooks Island Caspian terns (2008: 126 fish; 2009: 123 fish) were less than half those of Caspian terns nesting in the Columbia River estuary. If the current downward trend in the number of Caspian terns nesting on Brooks Island continues until the colony is no longer extant, the resulting declines in predation on salmonids would lead to increases in annual population growth rates (Δλ) of salmonid runs of just small fractions of one percentage point. The proposed enhancement of the Brooks Island Caspian tern colony to 3,000 individuals would at most cause declines in annual population growth rates of 0.3% for fall-run Chinook salmon and 0.02% for threatened spring-run Chinook salmon, assuming that smolt mortality from tern predation is 100% additive. This level of impact to the ESA-listed spring-run Chinook salmon stock is less than the level considered acceptable by the National Marine Fisheries Service (Δλ = 0.05%). Radio-tracking of Caspian terns nesting on Brooks Island revealed that the maximum foraging distance from the colony was 80 km. The median foraging distance from the colony was greater in 2009 compared to 2008 (20.6 km vs. 14.0 km), average number of foraging trips per day was higher (4.4 vs. 3.4 foraging trips), and average adult colony attendance was lower (43% vs. 52% of daylight hours). These results indicate that the colony was more food-limited during the 2009 breeding season, concurrent with anomalous downwelling along the coast of northern California and reduced availability and size of marine forage fishes, such as herring, sardines, and anchovies. Caspian terns used a number of core foraging areas within 30 km of the Brooks Island colony, both inside and just outside the Bay. Two large core foraging areas were close to or overlapped with the release site for juvenile salmonids in eastern San Pablo Bay, where > 10 million hatchery-raised smolts were released from net pens during both the 2008 and 2009 tern nesting seasons. This finding supports the hypothesis that most juvenile salmonids consumed by terns nesting at the Brooks Island colony were captured at or near the release site. Individual Caspian terns displayed foraging site fidelity, suggesting that foraging at the release site for hatchery-raised salmonids was a learned behavior by some terns. The Brooks Island colony site is within foraging distance of adequate marine forage fish resources in most years, and Caspian terns nesting there are not dependent on juvenile salmonids as a food resource. Consumption of juvenile salmonids by Brooks Island terns would be largely curtailed by modification of hatchery release practices. Close

• 36. [Article] Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery

  The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information ...

  Citation × Citation Citation Abstract Copy Title: Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery Author: Lin, Pei-Chien The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information to evaluate the effects of alternative policies on the benefits provided to different constituencies. Over the past decade, economists have developed techniques to measure the benefits provided by such nonmarket goods. The random utility model (RUM), a variant of the travel cost model (TCM), is one of the techniques developed by economists to measure benefits associated with changes in the quantity or quality of nonmarket goods. The advantages of using RUN over other techniques are that the substitution effects among different sites providing similar recreational activities or services can be incorporated into the model to avoid overestimating the benefits provided by a certain site. Redacted for Privacy RUM is used in this thesis to measure the welfare changes caused by a reduction in fishing quality or closure of one of the sites in a recreational fishing area. The focus of this study is the spring chinook recreational fishery in the lower Willamette River. The 1988 Willamette Run Spring Chinook Survey and the 1988 Willamette River Spring Chinook Salmon Run Report, published by the Oregon Department of Fish and Wildlife, provide the data set to do this research. Three definitions of travel costs, TC1, TC2, and TC3 are derived from the data set and used alternatively in the RUM framework. Specific objectives of this thesis include: (1) estimate how the attributes of a site (travel cost, congestion level and fishing quality of the site) will affect the individual's site choice; and (2) estimate the welfare changes arising from the two hypothetical policies which change the quality of fishing experience and which restrict the access of anglers to a certain fishing site. The results indicate that fishing sites on the Willamette River are more attractive to anglers if the fishing quality is increased, if more people visit, and if the site is relatively inexpensive to reach. The results of the elasticities of probabilities show that the travel cost has the largest effect on individual site choice decision. For different definitions of travel costs, the estimated welfare losses caused by the first hypothetical policy (of a reduction in fishing. success) for a representative angler in the sample are $ 0.37, $ 0.91, and $ 0.47 respectively, per trip. For different definitions of travel costs, the aggregate welfare losses associated with this hypothetical policy are $ 82,309, $ 202,436, and $ 104,555. For different definitions of travel costs, the estimated welfare losses caused by the second hypothetical policy (a closure of one site) for a representative angler in the sample are $ 3.82, $ 54.91, and $ 4.83 per trip respectively. The aggregate welfare losses associated with this hypothetical policy are $ 849,786, $ 12,215,114, and $ 1,074,467 respectively for TC1, TC2, and TC3. Assuming that these two policies achieved the same objectives, the policy implication of these results is that the first policy is preferred because the welfare loss is much smaller than the second one. There is a methodological implication suggested by one of the findings. A few of the individual results obtained from the model with TC2 travel cost violate the assumption of utility maximization. This implies that TC2 may over-value the opportunity cost of time in the travel cost variable, and points out the uncertain of the definition of travel cost used in RUM analyses. Title: Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery Author: Lin, Pei-Chien The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information to evaluate the effects of alternative policies on the benefits provided to different constituencies. Over the past decade, economists have developed techniques to measure the benefits provided by such nonmarket goods. The random utility model (RUM), a variant of the travel cost model (TCM), is one of the techniques developed by economists to measure benefits associated with changes in the quantity or quality of nonmarket goods. The advantages of using RUN over other techniques are that the substitution effects among different sites providing similar recreational activities or services can be incorporated into the model to avoid overestimating the benefits provided by a certain site. Redacted for Privacy RUM is used in this thesis to measure the welfare changes caused by a reduction in fishing quality or closure of one of the sites in a recreational fishing area. The focus of this study is the spring chinook recreational fishery in the lower Willamette River. The 1988 Willamette Run Spring Chinook Survey and the 1988 Willamette River Spring Chinook Salmon Run Report, published by the Oregon Department of Fish and Wildlife, provide the data set to do this research. Three definitions of travel costs, TC1, TC2, and TC3 are derived from the data set and used alternatively in the RUM framework. Specific objectives of this thesis include: (1) estimate how the attributes of a site (travel cost, congestion level and fishing quality of the site) will affect the individual's site choice; and (2) estimate the welfare changes arising from the two hypothetical policies which change the quality of fishing experience and which restrict the access of anglers to a certain fishing site. The results indicate that fishing sites on the Willamette River are more attractive to anglers if the fishing quality is increased, if more people visit, and if the site is relatively inexpensive to reach. The results of the elasticities of probabilities show that the travel cost has the largest effect on individual site choice decision. For different definitions of travel costs, the estimated welfare losses caused by the first hypothetical policy (of a reduction in fishing. success) for a representative angler in the sample are $ 0.37, $ 0.91, and $ 0.47 respectively, per trip. For different definitions of travel costs, the aggregate welfare losses associated with this hypothetical policy are $ 82,309, $ 202,436, and $ 104,555. For different definitions of travel costs, the estimated welfare losses caused by the second hypothetical policy (a closure of one site) for a representative angler in the sample are $ 3.82, $ 54.91, and $ 4.83 per trip respectively. The aggregate welfare losses associated with this hypothetical policy are $ 849,786, $ 12,215,114, and $ 1,074,467 respectively for TC1, TC2, and TC3. Assuming that these two policies achieved the same objectives, the policy implication of these results is that the first policy is preferred because the welfare loss is much smaller than the second one. There is a methodological implication suggested by one of the findings. A few of the individual results obtained from the model with TC2 travel cost violate the assumption of utility maximization. This implies that TC2 may over-value the opportunity cost of time in the travel cost variable, and points out the uncertain of the definition of travel cost used in RUM analyses. Close

• 37. [Article] Non-regulatory efforts to combat nonpoint source pollution in Oregon

  This report and accompanying program inventory have been prepared in support of the Oregon Department of Environmental Quality's statewide nonpoint source pollution control efforts and for use in the development ...

  Citation × Citation Citation Abstract Copy Title: Non-regulatory efforts to combat nonpoint source pollution in Oregon Author: Lindberg, Roberta J. This report and accompanying program inventory have been prepared in support of the Oregon Department of Environmental Quality's statewide nonpoint source pollution control efforts and for use in the development of Oregon's new federally mandated Coastal Nonpoint Pollution Control Program (CNPCP). When Congress reauthorized the Coastal Zone Management Act in 1990, it added significant new responsibilities for coastal states regarding water pollution from diffuse, widespread sources that in the past have not been regulated. Section 6217 of the Coastal Zone Act Reauthorization Amendments (CZARA) requires states to adopt enforceable programs to address nonpoint source pollution arising from agriculture, forestry, urban runoff, recreational boating and marinas, channelization, dams and eroding stream banks. "Nonpoint source pollution" in this context includes any discharge to the state's waters which is not regulated by the Clean Water Act's permit system, the National Pollutant Discharge Elimination System (NPDES). When Congress mandated the coastal nonpoint source program, it directed that states' coastal programs and water quality agencies work together in developing and implementing the program. In Oregon, the Department of Land Conservation and Development (DLCD) and the Department of Environmental Quality (DEQ) are jointly responsible for the development of the coastal nonpoint control program. DLCD's Coastal Management Program implements provisions of the federal Coastal Zone Management Act. DEQ's Water Quality Division manages the statewide nonpoint source control program pursuant to Section 319 of the Clean Water Act (CWA). Staff at DLCD's Coastal Management Program prepared an extensive report and analysis of Oregon's current array of enforceable programs and the extent to which those programs satisfy the federal requirements for the new coastal program. Gaps in program coverage were identified, and efforts to fill those gaps are currently in progress. This report is a companion to the DLCD gap analysis. However, instead of focusing on enforceable programs, this report highlights nonpoint source control and watershed management programs that rely on voluntary efforts to achieve their goals. Staff at DEQ have identified nine types of activities which, together with enforcement, make constitute an effective watershed management program. This report presents an inventory of the state and federal government efforts currently underway within the state of Oregon which contribute to the control of nonpoint source pollution but do not rely on a regulatory program to do so. This is a time of extensive reevaluation and reordering of natural resource priorities and strategies at both the state and federal levels. The Clinton Forest Summit and the Forest Ecosystem Management Assessment Team (FEMAT) process have been examining federal forest policy from top to bottom. The two major federal land management agencies, the Forest Service and the Bureau of Land Management, began reviewing their policies and practices well before the Forest Summit, and have made significant changes as a result. At the state level, the Watershed Health Initiative directed $10 million to two regions of the state during the 1993-95 biennium, in an unprecedented effort to restore salmon habitat and improve water quality. The impetus for change comes from the visible results of past natural resource management practices: the collapse of many native salmon runs and the decline in many other species leading to a great expansion of activity under the federal Endangered Species Act. The federal court logging injunction to protect the Northern Spotted Owl triggered much activity at the state and local levels in an effort to avoid further listings and the potential economic dislocations associated with them. Title: Non-regulatory efforts to combat nonpoint source pollution in Oregon Author: Lindberg, Roberta J. This report and accompanying program inventory have been prepared in support of the Oregon Department of Environmental Quality's statewide nonpoint source pollution control efforts and for use in the development of Oregon's new federally mandated Coastal Nonpoint Pollution Control Program (CNPCP). When Congress reauthorized the Coastal Zone Management Act in 1990, it added significant new responsibilities for coastal states regarding water pollution from diffuse, widespread sources that in the past have not been regulated. Section 6217 of the Coastal Zone Act Reauthorization Amendments (CZARA) requires states to adopt enforceable programs to address nonpoint source pollution arising from agriculture, forestry, urban runoff, recreational boating and marinas, channelization, dams and eroding stream banks. "Nonpoint source pollution" in this context includes any discharge to the state's waters which is not regulated by the Clean Water Act's permit system, the National Pollutant Discharge Elimination System (NPDES). When Congress mandated the coastal nonpoint source program, it directed that states' coastal programs and water quality agencies work together in developing and implementing the program. In Oregon, the Department of Land Conservation and Development (DLCD) and the Department of Environmental Quality (DEQ) are jointly responsible for the development of the coastal nonpoint control program. DLCD's Coastal Management Program implements provisions of the federal Coastal Zone Management Act. DEQ's Water Quality Division manages the statewide nonpoint source control program pursuant to Section 319 of the Clean Water Act (CWA). Staff at DLCD's Coastal Management Program prepared an extensive report and analysis of Oregon's current array of enforceable programs and the extent to which those programs satisfy the federal requirements for the new coastal program. Gaps in program coverage were identified, and efforts to fill those gaps are currently in progress. This report is a companion to the DLCD gap analysis. However, instead of focusing on enforceable programs, this report highlights nonpoint source control and watershed management programs that rely on voluntary efforts to achieve their goals. Staff at DEQ have identified nine types of activities which, together with enforcement, make constitute an effective watershed management program. This report presents an inventory of the state and federal government efforts currently underway within the state of Oregon which contribute to the control of nonpoint source pollution but do not rely on a regulatory program to do so. This is a time of extensive reevaluation and reordering of natural resource priorities and strategies at both the state and federal levels. The Clinton Forest Summit and the Forest Ecosystem Management Assessment Team (FEMAT) process have been examining federal forest policy from top to bottom. The two major federal land management agencies, the Forest Service and the Bureau of Land Management, began reviewing their policies and practices well before the Forest Summit, and have made significant changes as a result. At the state level, the Watershed Health Initiative directed $10 million to two regions of the state during the 1993-95 biennium, in an unprecedented effort to restore salmon habitat and improve water quality. The impetus for change comes from the visible results of past natural resource management practices: the collapse of many native salmon runs and the decline in many other species leading to a great expansion of activity under the federal Endangered Species Act. The federal court logging injunction to protect the Northern Spotted Owl triggered much activity at the state and local levels in an effort to avoid further listings and the potential economic dislocations associated with them. Close

• 38. [Article] Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon

  In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking ...

  Citation × Citation Citation Abstract Copy Title: Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon Author: Courter, Ian I. In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking from hatcheries over the past hundred years is often suggested to be a major cause. The listing of over two dozen runs of salmon under the Endangered Species Act has catalyzed a re-assessment of hatchery effects on naturally spawning salmon. Recent policies have placed a much greater emphasis on restoring runs of wild salmon rather than maintaining runs through stocking from hatchery production. Except at the most superficial level, there is no consensus about how to define "wild." Rather, there is a continuum of definitions for "wild" and each definition supports an implicit policy goal. The precise way in which "wild salmon" is defined potentially has profound policy implications. Ultimately, the choice of definition is a policy decision that incorporates science as one of several factors influencing the decision. A suite of options, often poorly articulated, for defining "wild" are available to policy makers who are selecting recovery goals. To test a subset of the available definitions of wild, I quantified the number of hatchery and naturally spawning salmon for 19 populations of Oregon coastal coho. "Wild" was defined by types 1 through 5 based on the number of hatchery fish released annually and the number of naturally spawning hatchery adults. As currently managed by the Oregon Department of Fish and Wildlife, the Oregon coast has a range of "types" of coho salmon. By clearly and explicitly defining "wild" as steps along a continuum, policy makers and managers can more effectively monitor and achieve specific salmon recovery goals. Title: Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon Author: Courter, Ian I. In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking from hatcheries over the past hundred years is often suggested to be a major cause. The listing of over two dozen runs of salmon under the Endangered Species Act has catalyzed a re-assessment of hatchery effects on naturally spawning salmon. Recent policies have placed a much greater emphasis on restoring runs of wild salmon rather than maintaining runs through stocking from hatchery production. Except at the most superficial level, there is no consensus about how to define "wild." Rather, there is a continuum of definitions for "wild" and each definition supports an implicit policy goal. The precise way in which "wild salmon" is defined potentially has profound policy implications. Ultimately, the choice of definition is a policy decision that incorporates science as one of several factors influencing the decision. A suite of options, often poorly articulated, for defining "wild" are available to policy makers who are selecting recovery goals. To test a subset of the available definitions of wild, I quantified the number of hatchery and naturally spawning salmon for 19 populations of Oregon coastal coho. "Wild" was defined by types 1 through 5 based on the number of hatchery fish released annually and the number of naturally spawning hatchery adults. As currently managed by the Oregon Department of Fish and Wildlife, the Oregon coast has a range of "types" of coho salmon. By clearly and explicitly defining "wild" as steps along a continuum, policy makers and managers can more effectively monitor and achieve specific salmon recovery goals. Close

• 39. [Article] Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression

  Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been ...

  Citation × Citation Citation Abstract Copy Title: Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression Author: Banks, Michael A., McArthur, Andrew G., Birkeland, Shanda R., Bernier, Jeremiah C., Cipriano, Michael J. Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been well described. Current methods, such as long serial analysis of gene expression (LongSAGE) and microarrays, allow gene expression to be analyzed for thousands of genes simultaneously. To investigate whether differential gene expression is observed between fall- and spring-run Chinook salmon from California's Central Valley, LongSAGE libraries were constructed. Three libraries containing between 25,512 and 29,372 sequenced tags (21 base pairs/tag) were generated using messenger RNA from the brains of adult Chinook salmon returning in fall and spring and from one ocean-caught Chinook salmon. Tags were annotated to genes using complementary DNA libraries from Atlantic salmon Salmo salar and rainbow trout O. mykiss. Differentially expressed genes, as estimated by differences in the number of sequence tags, were found in all pairwise comparisons of libraries (freshwater versus saltwater = 40 genes; fall versus spring = 11 genes; and spawning versus nonspawning = 51 genes). The gene for ependymin, an extracellular glycoprotein involved in behavioral plasticity in fish, exhibited the most differential expression among the three groupings. Reverse transcription polymerase chain reaction analysis verified the differential expression of ependymin between the fall- and spring-run samples. These LongSAGE libraries, the first reported for Chinook salmon, provide a window of the transcriptional changes during Chinook salmon return migration to freshwater and spawning and increase the amount of expressed sequence data. Title: Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression Author: Banks, Michael A., McArthur, Andrew G., Birkeland, Shanda R., Bernier, Jeremiah C., Cipriano, Michael J. Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been well described. Current methods, such as long serial analysis of gene expression (LongSAGE) and microarrays, allow gene expression to be analyzed for thousands of genes simultaneously. To investigate whether differential gene expression is observed between fall- and spring-run Chinook salmon from California's Central Valley, LongSAGE libraries were constructed. Three libraries containing between 25,512 and 29,372 sequenced tags (21 base pairs/tag) were generated using messenger RNA from the brains of adult Chinook salmon returning in fall and spring and from one ocean-caught Chinook salmon. Tags were annotated to genes using complementary DNA libraries from Atlantic salmon Salmo salar and rainbow trout O. mykiss. Differentially expressed genes, as estimated by differences in the number of sequence tags, were found in all pairwise comparisons of libraries (freshwater versus saltwater = 40 genes; fall versus spring = 11 genes; and spawning versus nonspawning = 51 genes). The gene for ependymin, an extracellular glycoprotein involved in behavioral plasticity in fish, exhibited the most differential expression among the three groupings. Reverse transcription polymerase chain reaction analysis verified the differential expression of ependymin between the fall- and spring-run samples. These LongSAGE libraries, the first reported for Chinook salmon, provide a window of the transcriptional changes during Chinook salmon return migration to freshwater and spawning and increase the amount of expressed sequence data. Close

• 40. [Article] Microsatellites Reveal Population Identity of Individual Pink Salmon to Allow Supportive Breeding of a Population at Risk of Extinction

  Efforts to restore depressed populations of Pacific salmon Oncorhynchus spp. are often hampered by the inability to assign population identity to individuals in an admixture. This knowledge is of particular ...

  Citation × Citation Citation Abstract Copy Title: Microsatellites Reveal Population Identity of Individual Pink Salmon to Allow Supportive Breeding of a Population at Risk of Extinction Author: Shaklee, James B., Bentzen, Paul, Olsen, Jeffrey B., Young, Sewall, Banks, Michael A. Efforts to restore depressed populations of Pacific salmon Oncorhynchus spp. are often hampered by the inability to assign population identity to individuals in an admixture. This knowledge is of particular concern in supportive breeding programs, in which misidentification of individuals to population may result in progeny of mixed heritage, which, in turn, results in the erosion of the genetic population structure and of the existing genetic diversity and local adaptations of the target population. We evaluated two classes of genetic markers, allozymes and microsatellites, for estimating population identity of pink salmon Oncorhynchus gorbuscha in a supportive breeding program on the Dungeness River in Washington State. Fall-run pink salmon of the Dungeness River are the target of restoration, but they presumably overlap, in terms of timing, with an earlier summer run. Both marker types revealed similarly low estimates of relative genetic differentiation ( <(theta)over cap> = 0.02), which suggests that there is little variation in allele frequency among populations. However, microsatellites provided a more accurate estimate of population identity. When applying a log-likelihood ratio criterion of greater than 1.3, 74.8% of individuals were correctly assigned to population using microsatellites (versus 3.1% of individuals using allozymes). The difference in assignment accuracy was best predicted by the statistic <(delta)over cap>, which estimates cumulative allele frequency differences among populations. Our results suggest that genetic markers with many alleles are preferred when populations exhibit little genetic differentiation (as is the case in pink salmon), because <(delta)over cap> is more likely to be large, presumably as a result of genetic drift at each allele. The use of microsatellites to select fall-run pink salmon for supportive breeding confirmed the run-timing overlap and prevented unintentional crosses between the two populations. Title: Microsatellites Reveal Population Identity of Individual Pink Salmon to Allow Supportive Breeding of a Population at Risk of Extinction Author: Shaklee, James B., Bentzen, Paul, Olsen, Jeffrey B., Young, Sewall, Banks, Michael A. Efforts to restore depressed populations of Pacific salmon Oncorhynchus spp. are often hampered by the inability to assign population identity to individuals in an admixture. This knowledge is of particular concern in supportive breeding programs, in which misidentification of individuals to population may result in progeny of mixed heritage, which, in turn, results in the erosion of the genetic population structure and of the existing genetic diversity and local adaptations of the target population. We evaluated two classes of genetic markers, allozymes and microsatellites, for estimating population identity of pink salmon Oncorhynchus gorbuscha in a supportive breeding program on the Dungeness River in Washington State. Fall-run pink salmon of the Dungeness River are the target of restoration, but they presumably overlap, in terms of timing, with an earlier summer run. Both marker types revealed similarly low estimates of relative genetic differentiation ( <(theta)over cap> = 0.02), which suggests that there is little variation in allele frequency among populations. However, microsatellites provided a more accurate estimate of population identity. When applying a log-likelihood ratio criterion of greater than 1.3, 74.8% of individuals were correctly assigned to population using microsatellites (versus 3.1% of individuals using allozymes). The difference in assignment accuracy was best predicted by the statistic <(delta)over cap>, which estimates cumulative allele frequency differences among populations. Our results suggest that genetic markers with many alleles are preferred when populations exhibit little genetic differentiation (as is the case in pink salmon), because <(delta)over cap> is more likely to be large, presumably as a result of genetic drift at each allele. The use of microsatellites to select fall-run pink salmon for supportive breeding confirmed the run-timing overlap and prevented unintentional crosses between the two populations. Close