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• 391. [Article] The effects of harvesting Pacific hake (Merluccius productus) on the offshore community : the results of a multi-species model

  The effects of harvesting Pacific hake (Merluccius productus) were examined with a multi-species numerical model composed of seven logistic growth equations coupled by a food web. The food web was composed ...

  Citation × Citation Citation Abstract Copy Title: The effects of harvesting Pacific hake (Merluccius productus) on the offshore community : the results of a multi-species model Author: Gartz, Russell G. The effects of harvesting Pacific hake (Merluccius productus) were examined with a multi-species numerical model composed of seven logistic growth equations coupled by a food web. The food web was composed of: California sea lions (Zalophus californianus), hake, sablefish (Anaplopoma fimbria), spiny dogfish (Squalus acanthias), a generic rockfish species (Sebastes spp.), Northern anchovy (Engraulis mordax), and a generic euphausiid species (as an example, Pacific krill, Euphausia pacifica). The model was tuned to mimic stock assessment biomass estimates for the years 1980 to 1991, after which a short term experiment and a sensitivity analysis were conducted. The short term experiment used a factorial design, with hake fishing and fishing for rockfish, sablefish, and anchovy as treatments. It was analyzed with scale analysis techniques. The results indicate that hake (from a management viewpoint) is potentially most important in the offshore community as a prey item for sea lions and as a predator on anchovies, but hake fishing mortality had a small effect on either population during the time span of the experiment. Results also suggest that hake has little or no competitive interaction with other species that are trophically similar. Increased harvesting of hake would probably do little to increase the biomass of rockfish or sablefish. The general conclusion of both the sensitivity analysis and the experiment is that species below their carrying capacity are mostly affected by changes in growth and removal processes while species close to their carrying capacity are mostly affected by processes controlling prey availability. A forty year projection from 1991 to 2031 was conducted to examine the effects of hake fishing on sea lion and anchovy biomass. Results indicate that sea lion biomass will vary inversely with hake fishing effort, while anchovy biomass is directly proportional to hake fishing effort. Results also indicate that hake experience environmental conditions not favorable to recruitment. During favorable conditions the hake population builds up a "surplus" that carries it through periods of unfavorable conditions. Increased hake fishing effort reduces the response of the population to favorable conditions. The results of this research constitute a step from the theory toward the practice of proactive multi-species and ecosystem management. Title: The effects of harvesting Pacific hake (Merluccius productus) on the offshore community : the results of a multi-species model Author: Gartz, Russell G. The effects of harvesting Pacific hake (Merluccius productus) were examined with a multi-species numerical model composed of seven logistic growth equations coupled by a food web. The food web was composed of: California sea lions (Zalophus californianus), hake, sablefish (Anaplopoma fimbria), spiny dogfish (Squalus acanthias), a generic rockfish species (Sebastes spp.), Northern anchovy (Engraulis mordax), and a generic euphausiid species (as an example, Pacific krill, Euphausia pacifica). The model was tuned to mimic stock assessment biomass estimates for the years 1980 to 1991, after which a short term experiment and a sensitivity analysis were conducted. The short term experiment used a factorial design, with hake fishing and fishing for rockfish, sablefish, and anchovy as treatments. It was analyzed with scale analysis techniques. The results indicate that hake (from a management viewpoint) is potentially most important in the offshore community as a prey item for sea lions and as a predator on anchovies, but hake fishing mortality had a small effect on either population during the time span of the experiment. Results also suggest that hake has little or no competitive interaction with other species that are trophically similar. Increased harvesting of hake would probably do little to increase the biomass of rockfish or sablefish. The general conclusion of both the sensitivity analysis and the experiment is that species below their carrying capacity are mostly affected by changes in growth and removal processes while species close to their carrying capacity are mostly affected by processes controlling prey availability. A forty year projection from 1991 to 2031 was conducted to examine the effects of hake fishing on sea lion and anchovy biomass. Results indicate that sea lion biomass will vary inversely with hake fishing effort, while anchovy biomass is directly proportional to hake fishing effort. Results also indicate that hake experience environmental conditions not favorable to recruitment. During favorable conditions the hake population builds up a "surplus" that carries it through periods of unfavorable conditions. Increased hake fishing effort reduces the response of the population to favorable conditions. The results of this research constitute a step from the theory toward the practice of proactive multi-species and ecosystem management. Close

• 392. [Article] Plants, plant communities, net production and tide levels; the ecological biogeography of the Nehalem salt marshes, Tillamook County, Oregon

  Nehalem Bay is located on the northern coast of Oregon in Tillamook County and contains approximately 243 ha of salt marsh. The Nehalem marshes occur as islands and land-tied units. West Island is the ...

  Citation × Citation Citation Abstract Copy Title: Plants, plant communities, net production and tide levels; the ecological biogeography of the Nehalem salt marshes, Tillamook County, Oregon Author: Eilers, H. Peter Nehalem Bay is located on the northern coast of Oregon in Tillamook County and contains approximately 243 ha of salt marsh. The Nehalem marshes occur as islands and land-tied units. West Island is the largest marsh island with an area of 82.9 ha and a maximum elevation of 3.079 m above mean lower low water. Three divisions on West Island based on inundation period have been identified: intertidal marsh, below mean high water; transitional marsh, from MHW to 2.76 m above MLLW; and extratidal marsh, above 2.76 m. West Island may be further subdivided into four topographic units based on the steepness of the elevation gradient: edge marsh, from.the lower margin to 2.00 m; low marsh, 2.00 to 2.36 m; transitional marsh, 2.36 to 2.76 m; and high marsh, 2.76 m and above. Creek density is low for the lower intertidal marsh, for the edge marsh, and.for the higher extratidal marsh; and is high for the upper intertidal and transitional marsh. Salt marsh vegetation-on West Island was sampled by harvesting aboveground biomass along seven transects at two-month intervals from May of 1972 to September of 1972. Plant species diversity increases with elevation and each species displays a particular elevation range. Analysis of dry-weight data by an ordination routine suggests the presence of 11 plant communities along the elevation gradient on West Island. Plant communities named by dominant species are Triglochin, Scirpus, Carex (tall and short phases), Carex-Deschampsia-Triglochin, Triglochin-Deschampsia, Carex-Deschampsia-Triglochin-Agrostis, Juncus- Agrostis, Juncus-Agrostis-Festuca, Aster-Potentilla-Oenanthe, Carex- Aster-Oenanthe, and Picea-Salix. Plant communities are readily identified by signatures on aerial photographs. Net aerial production on West Island increases with elevation and varies from a minimum of 518 g/m2/yr for the Triglochin community to a maximum of 1936 g/m2/yr for the Aster-Potentilla-Oenanthe community. The community mean net aerial productivity is 1388 g/m2/yr. More than 90 percent of the intertidal marsh net aerial production is removed to the estuary as organic detritus, and net aerial production in the high marsh is rapidly incorporated into marsh soil. It is estimated that approximately 56 percent of all net aerial production on West Island is transported to the estuary by the tides. It is recommended that salt marshes be preserved in their natural state and new salt marshes be created to ensure the continued high productivity of estuarine ecosystems in Oregon. Title: Plants, plant communities, net production and tide levels; the ecological biogeography of the Nehalem salt marshes, Tillamook County, Oregon Author: Eilers, H. Peter Nehalem Bay is located on the northern coast of Oregon in Tillamook County and contains approximately 243 ha of salt marsh. The Nehalem marshes occur as islands and land-tied units. West Island is the largest marsh island with an area of 82.9 ha and a maximum elevation of 3.079 m above mean lower low water. Three divisions on West Island based on inundation period have been identified: intertidal marsh, below mean high water; transitional marsh, from MHW to 2.76 m above MLLW; and extratidal marsh, above 2.76 m. West Island may be further subdivided into four topographic units based on the steepness of the elevation gradient: edge marsh, from.the lower margin to 2.00 m; low marsh, 2.00 to 2.36 m; transitional marsh, 2.36 to 2.76 m; and high marsh, 2.76 m and above. Creek density is low for the lower intertidal marsh, for the edge marsh, and.for the higher extratidal marsh; and is high for the upper intertidal and transitional marsh. Salt marsh vegetation-on West Island was sampled by harvesting aboveground biomass along seven transects at two-month intervals from May of 1972 to September of 1972. Plant species diversity increases with elevation and each species displays a particular elevation range. Analysis of dry-weight data by an ordination routine suggests the presence of 11 plant communities along the elevation gradient on West Island. Plant communities named by dominant species are Triglochin, Scirpus, Carex (tall and short phases), Carex-Deschampsia-Triglochin, Triglochin-Deschampsia, Carex-Deschampsia-Triglochin-Agrostis, Juncus- Agrostis, Juncus-Agrostis-Festuca, Aster-Potentilla-Oenanthe, Carex- Aster-Oenanthe, and Picea-Salix. Plant communities are readily identified by signatures on aerial photographs. Net aerial production on West Island increases with elevation and varies from a minimum of 518 g/m2/yr for the Triglochin community to a maximum of 1936 g/m2/yr for the Aster-Potentilla-Oenanthe community. The community mean net aerial productivity is 1388 g/m2/yr. More than 90 percent of the intertidal marsh net aerial production is removed to the estuary as organic detritus, and net aerial production in the high marsh is rapidly incorporated into marsh soil. It is estimated that approximately 56 percent of all net aerial production on West Island is transported to the estuary by the tides. It is recommended that salt marshes be preserved in their natural state and new salt marshes be created to ensure the continued high productivity of estuarine ecosystems in Oregon. Close

• 393. [Article] Blue-Green Consumption: Determinants for Eco-Labelled Seafood Purchasing in Sweden

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: Blue-Green Consumption: Determinants for Eco-Labelled Seafood Purchasing in Sweden Author: Rönnbäck, Patrik, Jonell, Malin, Troell, Max, Crona, Beatrice Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: Blue-Green Consumption: Determinants for Eco-Labelled Seafood Purchasing in Sweden Author: Rönnbäck, Patrik, Jonell, Malin, Troell, Max, Crona, Beatrice Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 394. [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

• 395. [Article] Effects of Construction of an Infiltration Gallery Water Intake (Permit ID No. 00-32) on Cow Creek on Umpqua River Cutthroat Trout and Oregon Coast Coho Salmon : Biological Opinion

  In a January 26, 2000 letter, the Portland District Army Corps of Engineers (COE) requested Endangered Species Act (ESA) Section 7 informal consultation with the National Marine Fisheries Service (NMFS) ...

  Citation × Citation Citation Abstract Copy Title: Effects of Construction of an Infiltration Gallery Water Intake (Permit ID No. 00-32) on Cow Creek on Umpqua River Cutthroat Trout and Oregon Coast Coho Salmon : Biological Opinion In a January 26, 2000 letter, the Portland District Army Corps of Engineers (COE) requested Endangered Species Act (ESA) Section 7 informal consultation with the National Marine Fisheries Service (NMFS) on the proposed issuance of a Clean Water Act Section 404 permit (Permit ID No. 00-32) to allow an instream construction project. The applicant for this permit, the City of Glendale (City) proposes to construct an infiltration gallery-type municipal water intake in Cow Creek, a tributary of the South Umpqua River in Douglas County, Oregon. The new water intake, which would be buried beneath the bed of the creek, would replace an existing screened intake in the creek which has deteriorated and which is thought to have insufficient capacity. The COE has proposed conditions on the permit that would lessen the adverse effects of the proposed actions on aquatic organisms. In the January 26 letter, the COE determined that the Umpqua River (UR) cutthroat trout (Oncorhynchus clarki), listed as endangered under the ESA, and Oregon Coast (OC) coho salmon (O. kisutch), listed as threatened under the ESA, may occur within the project area, which has been proposed as critical habitat for these species. The COE also determined that these species may be affected by the proposed projects, but that individuals of the species would not be adversely affected. After review of the information provided by the COE and additional investigation, however, the NMFS concluded that more than a negligible likelihood of adverse effect to individuals of the listed species is likely because substantial in-water work is proposed during a period in which individuals of one or both species is likely to occur at and near the site. Based on this information, the COE agreed to modify its effect determination to likely to adversely affect. Title: Effects of Construction of an Infiltration Gallery Water Intake (Permit ID No. 00-32) on Cow Creek on Umpqua River Cutthroat Trout and Oregon Coast Coho Salmon : Biological Opinion In a January 26, 2000 letter, the Portland District Army Corps of Engineers (COE) requested Endangered Species Act (ESA) Section 7 informal consultation with the National Marine Fisheries Service (NMFS) on the proposed issuance of a Clean Water Act Section 404 permit (Permit ID No. 00-32) to allow an instream construction project. The applicant for this permit, the City of Glendale (City) proposes to construct an infiltration gallery-type municipal water intake in Cow Creek, a tributary of the South Umpqua River in Douglas County, Oregon. The new water intake, which would be buried beneath the bed of the creek, would replace an existing screened intake in the creek which has deteriorated and which is thought to have insufficient capacity. The COE has proposed conditions on the permit that would lessen the adverse effects of the proposed actions on aquatic organisms. In the January 26 letter, the COE determined that the Umpqua River (UR) cutthroat trout (Oncorhynchus clarki), listed as endangered under the ESA, and Oregon Coast (OC) coho salmon (O. kisutch), listed as threatened under the ESA, may occur within the project area, which has been proposed as critical habitat for these species. The COE also determined that these species may be affected by the proposed projects, but that individuals of the species would not be adversely affected. After review of the information provided by the COE and additional investigation, however, the NMFS concluded that more than a negligible likelihood of adverse effect to individuals of the listed species is likely because substantial in-water work is proposed during a period in which individuals of one or both species is likely to occur at and near the site. Based on this information, the COE agreed to modify its effect determination to likely to adversely affect. Close

• 396. [Article] Ultraviolet radiation as an environmental stressor of amphibians

  My thesis explored the effects of and potential mediating mechanisms for an important environmental stressor, ultraviolet-B (UVB) radiation. UVB radiation has negative effects on organisms in both terrestrial ...

  Citation × Citation Citation Abstract Copy Title: Ultraviolet radiation as an environmental stressor of amphibians Author: Bancroft, Betsy A. My thesis explored the effects of and potential mediating mechanisms for an important environmental stressor, ultraviolet-B (UVB) radiation. UVB radiation has negative effects on organisms in both terrestrial and aquatic systems. I used meta-analysis to quantify the effects of UVB radiation on a diversity of aquatic organisms (Chapter 2). UVB negatively affects aquatic organisms by reducing both survival and growth. In particular, UVB reduces growth of embryos more than any other life history stage. Some taxonomic groups may be more affected by UVB radiation than others. In our analysis, the growth of members of the kingdom Protozoa was suppressed by UVB radiation to a greater degree than any other kingdom. These analyses suggest that UVB is an important stressor in both freshwater and marine systems. Amphibians are a common component of freshwater systems and are experiencing world-wide population declines. These declines may be due to a number of causes including habitat loss, introduced species, global climate change, disease, toxic chemicals and UVB radiation. I used meta-analytic techniques to quantify the effects of UVB radiation on amphibians. By synthesizing the results of 41 articles on the effects of UVB radiation on amphibians (Chapter 3), I found a nearly 2-fold reduction in survival of amphibians exposed to UVB radiation. Salamanders (caudates) appear to be more susceptible to damage from UVB than frogs or toads (anurans). Moreover, survival of larvae was much lower than survival of embryos or metamorphic individuals under UVB radiation. In addition, I used factorial meta-analytic techniques to explore the interaction between UVB radiation and other stressors in amphibian habitats. UVB radiation acted synergistically with other stressors to reduce survival of amphibians. Behavioral avoidance of UVB radiation may help mediate the negative effects of UVB radiation on amphibians. In aquatic systems, behavioral avoidance usually requires movement out of shallow water, where UVB levels can be high, into deeper waters with lower UVB transmittance. However, these two microhabitats have very different thermal profiles, creating a trade-off between exploiting warm waters with high UVB levels and avoiding UVB by seeking cooler, deeper regions of ponds. I explored the microhabitat use of larvae of four species through a series of laboratory experiments, field experiments, and observational field transects at three different amphibian habitats (Chapter 4). Larvae did not avoid UVB radiation in either the laboratory or field experiments. Larvae in thermal gradients selected relatively high temperatures regardless of the UVB exposure at these temperatures. In field transects, salamander larvae were most common in deeper, cooler waters where UVB levels were lower. In contrast, anuran larvae were frequently observed in the warmer and shallower regions of each habitat. These regions also had the highest UVB levels, suggesting that anuran larvae are exposed to high levels of UVB due to thermoregulatory behavior. Behavioral avoidance of UVB radiation is not the only mechanism amphibians may use to prevent damage from UVB. Pigments such as melanin may allow larvae to exploit warm shallow waters by absorbing harmful UVB radiation before it causes cellular damage. I tested the efficacy of melanin as a photoprotective pigment in the larvae of two species, Rana cascadae and Pseudacris regilla (Chapter 5). I found no evidence of a photoprotective function for melanin in these larvae. In contrast, lighter colored tadpoles grew more under UVB radiation compared to darker colored tadpoles. Overall, exposure to UVB reduced survival of P. regilla larvae and reduced growth of R. cascadae larvae. Larvae of both of these species were frequently observed in very shallow water with intense solar radiation. This thesis emphasizes the importance of UVB radiation as an environmental stressor in aquatic habitats. Many aquatic organisms are negatively affected by UVB exposure. My thesis work quantitatively demonstrated that UVB radiation is one factor that reduces survival of amphibians and suggests that some species are exposed to high levels of UVB radiation in natural habitats. While UVB radiation is not the sole cause of amphibian population declines, my work suggests that UVB radiation is an important stressor for amphibians that should not be overlooked. In addition, UVB radiation is clearly an important stressor for many other aquatic organisms. Future work should consider the effects of UVB in aquatic systems, particularly the effects of UVB radiation on community structure and ecosystem function. Title: Ultraviolet radiation as an environmental stressor of amphibians Author: Bancroft, Betsy A. My thesis explored the effects of and potential mediating mechanisms for an important environmental stressor, ultraviolet-B (UVB) radiation. UVB radiation has negative effects on organisms in both terrestrial and aquatic systems. I used meta-analysis to quantify the effects of UVB radiation on a diversity of aquatic organisms (Chapter 2). UVB negatively affects aquatic organisms by reducing both survival and growth. In particular, UVB reduces growth of embryos more than any other life history stage. Some taxonomic groups may be more affected by UVB radiation than others. In our analysis, the growth of members of the kingdom Protozoa was suppressed by UVB radiation to a greater degree than any other kingdom. These analyses suggest that UVB is an important stressor in both freshwater and marine systems. Amphibians are a common component of freshwater systems and are experiencing world-wide population declines. These declines may be due to a number of causes including habitat loss, introduced species, global climate change, disease, toxic chemicals and UVB radiation. I used meta-analytic techniques to quantify the effects of UVB radiation on amphibians. By synthesizing the results of 41 articles on the effects of UVB radiation on amphibians (Chapter 3), I found a nearly 2-fold reduction in survival of amphibians exposed to UVB radiation. Salamanders (caudates) appear to be more susceptible to damage from UVB than frogs or toads (anurans). Moreover, survival of larvae was much lower than survival of embryos or metamorphic individuals under UVB radiation. In addition, I used factorial meta-analytic techniques to explore the interaction between UVB radiation and other stressors in amphibian habitats. UVB radiation acted synergistically with other stressors to reduce survival of amphibians. Behavioral avoidance of UVB radiation may help mediate the negative effects of UVB radiation on amphibians. In aquatic systems, behavioral avoidance usually requires movement out of shallow water, where UVB levels can be high, into deeper waters with lower UVB transmittance. However, these two microhabitats have very different thermal profiles, creating a trade-off between exploiting warm waters with high UVB levels and avoiding UVB by seeking cooler, deeper regions of ponds. I explored the microhabitat use of larvae of four species through a series of laboratory experiments, field experiments, and observational field transects at three different amphibian habitats (Chapter 4). Larvae did not avoid UVB radiation in either the laboratory or field experiments. Larvae in thermal gradients selected relatively high temperatures regardless of the UVB exposure at these temperatures. In field transects, salamander larvae were most common in deeper, cooler waters where UVB levels were lower. In contrast, anuran larvae were frequently observed in the warmer and shallower regions of each habitat. These regions also had the highest UVB levels, suggesting that anuran larvae are exposed to high levels of UVB due to thermoregulatory behavior. Behavioral avoidance of UVB radiation is not the only mechanism amphibians may use to prevent damage from UVB. Pigments such as melanin may allow larvae to exploit warm shallow waters by absorbing harmful UVB radiation before it causes cellular damage. I tested the efficacy of melanin as a photoprotective pigment in the larvae of two species, Rana cascadae and Pseudacris regilla (Chapter 5). I found no evidence of a photoprotective function for melanin in these larvae. In contrast, lighter colored tadpoles grew more under UVB radiation compared to darker colored tadpoles. Overall, exposure to UVB reduced survival of P. regilla larvae and reduced growth of R. cascadae larvae. Larvae of both of these species were frequently observed in very shallow water with intense solar radiation. This thesis emphasizes the importance of UVB radiation as an environmental stressor in aquatic habitats. Many aquatic organisms are negatively affected by UVB exposure. My thesis work quantitatively demonstrated that UVB radiation is one factor that reduces survival of amphibians and suggests that some species are exposed to high levels of UVB radiation in natural habitats. While UVB radiation is not the sole cause of amphibian population declines, my work suggests that UVB radiation is an important stressor for amphibians that should not be overlooked. In addition, UVB radiation is clearly an important stressor for many other aquatic organisms. Future work should consider the effects of UVB in aquatic systems, particularly the effects of UVB radiation on community structure and ecosystem function. Close

• 397. [Article] Pacific lamprey research and restoration project : annual report 1998

  This document is the 1998 annual progress report for studies of Pacific lampreys (Lampetra tridentata) conducted by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Columbia River Inter-Tribal ...

  Citation × Citation Citation Abstract Copy Title: Pacific lamprey research and restoration project : annual report 1998 Author: Close, David A. This document is the 1998 annual progress report for studies of Pacific lampreys (Lampetra tridentata) conducted by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Columbia River Inter-Tribal Fish Commission, and University of Minnesota (U of M). Bonneville Power Administration (BPA) funded activities through Project 94-026. The Pacific Lamprey Research and Restoration Project began after completion of a status report of Pacific lamprey in the Columbia River in 1995. The project started as a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Columbia River Inter-Tribal Fish Commission (CRITFC), and Oregon State University (OSU). Lamprey are a valuable subsistence food and cultural resource for Native Americans of the Pacific Northwest. The once abundant Pacific lampreys above Bonneville Dam are currently depressed (Close et al. 1995). Declines in Pacific lampreys have impacted treaty secured fishing opportunities by limiting tribal members catch and access to Pacific lampreys in the interior Columbia basin. Tribal members now harvest lampreys in lower Columbia River locations such as Willamette Falls near Oregon City, Oregon. Pacific lampreys are also an important part of the food web of North Pacific ecosystems, both as predator (Beamish 1980; Pike 1951; Roos and Gillohousin 1973), and prey (Semekula and Larkin 1968; Galbreath 1979; Roffe and Mate 1984; Merrell 1959; Wolf and Jones 1989) and as a vehicle for recruitment of marine nutrients. The decline of Pacific lampreys in the interior Columbia River basin has become a major concern. Effective recovery measures for Pacific lampreys can only be developed after we increase our knowledge of the biology and factors that are limiting the various life history stages. Prior to developing a restoration plan, we have carried out studies to review status, distribution, abundance, homing ability, and stock structure. These studies will culminate in the development and implementation of a restoration plan for the Umatilla River. Multiple pass electrofishing surveys to assess densities and distribution of lamprey larvae in the Umatilla River were conducted in 1998. Electrofishing surveys in the Umatilla River are useful for baseline comparison. Forty-two index sites were sampled from the mouth to river kilometer (RK) 124. Lamprey larvae were found in 4 of the 42 index plots. All sites with larvae were found at and below RK 9.3. Nine larvae were captured during the surveys. However, no larvae were caught on the second pass in each plot. Pacific lamprey larvae and adult lampreys were studied to determine their ability to produce and detect pheromones. Larval gall bladders were removed and gall bladder fluid was extracted and analyzed by high performance liquid chromatography (HPLC). Adult lampreys ability to detect pheromones were tested using electro-olfactogram (EOG) methods. Fifteen compounds including Petromyzonol sulfate (PS), a migratory pheromone found in sea lamprey larvae (Petromyzon marinus) (Li et al. 1995) were tested. Larval lampreys produced large amounts of (PS). Adult Pacific lamprey can detect PS and have an olfactory sensitivity to pheromones that is similar to sea lampreys. iv Pacific lamprey abundance, as indexed by fish ladder counts in 1998, was; Bonneville 37,478; The Dalles 7,665; John Day 12,579; McNary 3,393; Ice Harbor 763; Lower Monumental 69; Little Goose 90; Lower Granite 110; Rock Island 1,410; and Rock Reach 819 dams, respectively. Enumerating Pacific lamprey at counting stations remained extremely problematic, since excessive up- and downstream movement at the counting windows reduces the confidence in fish ladder passage estimates. This may be an indication of passage problems encountered by Pacific lampreys. In-season homing of Pacific lamprey was studied using radio telemetry. Pacific lampery were captured at Willamette Falls and Bonneville Dam, outfitted with radio transmitters and released approximately 26 km downstream of the Willamette River confluence. A total of 50 fish were instrumented. Results will be presented in next year’s report. Natal homing was also investigated using mtDNA analysis of fish captured at Bonneville Dam and from Willamette Falls. These results will also be presented next year. We collected lamprey tissues, from fish captured in several locations throughout the Columbia River Basin, to develop a genetic database for use in determining population structure. Additional samples for populations outside the Columbia River Basin were used to scale the results. Results from this investigation will be presented in next year’s annual report. Since the initiation of the CTUIR lamprey research and restoration project, additional lamprey studies have been proposed that have created uncertainties regarding the prioritization of projects and needs of lampreys. At the request of the Northwest Power Planning Council, a multi-agency Pacific lamprey technical workgroup (TWG) was established in 1996. Annual meetings are held to coordinate projects and prioritize research needs. The TWG identified critical uncertainties and needs to help in determining priorities of ongoing and proposed projects (Appendix A). Finally, an annotated bibliography of relevant lamprey literature was compiled (Appendix B). Title: Pacific lamprey research and restoration project : annual report 1998 Author: Close, David A. This document is the 1998 annual progress report for studies of Pacific lampreys (Lampetra tridentata) conducted by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Columbia River Inter-Tribal Fish Commission, and University of Minnesota (U of M). Bonneville Power Administration (BPA) funded activities through Project 94-026. The Pacific Lamprey Research and Restoration Project began after completion of a status report of Pacific lamprey in the Columbia River in 1995. The project started as a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), Columbia River Inter-Tribal Fish Commission (CRITFC), and Oregon State University (OSU). Lamprey are a valuable subsistence food and cultural resource for Native Americans of the Pacific Northwest. The once abundant Pacific lampreys above Bonneville Dam are currently depressed (Close et al. 1995). Declines in Pacific lampreys have impacted treaty secured fishing opportunities by limiting tribal members catch and access to Pacific lampreys in the interior Columbia basin. Tribal members now harvest lampreys in lower Columbia River locations such as Willamette Falls near Oregon City, Oregon. Pacific lampreys are also an important part of the food web of North Pacific ecosystems, both as predator (Beamish 1980; Pike 1951; Roos and Gillohousin 1973), and prey (Semekula and Larkin 1968; Galbreath 1979; Roffe and Mate 1984; Merrell 1959; Wolf and Jones 1989) and as a vehicle for recruitment of marine nutrients. The decline of Pacific lampreys in the interior Columbia River basin has become a major concern. Effective recovery measures for Pacific lampreys can only be developed after we increase our knowledge of the biology and factors that are limiting the various life history stages. Prior to developing a restoration plan, we have carried out studies to review status, distribution, abundance, homing ability, and stock structure. These studies will culminate in the development and implementation of a restoration plan for the Umatilla River. Multiple pass electrofishing surveys to assess densities and distribution of lamprey larvae in the Umatilla River were conducted in 1998. Electrofishing surveys in the Umatilla River are useful for baseline comparison. Forty-two index sites were sampled from the mouth to river kilometer (RK) 124. Lamprey larvae were found in 4 of the 42 index plots. All sites with larvae were found at and below RK 9.3. Nine larvae were captured during the surveys. However, no larvae were caught on the second pass in each plot. Pacific lamprey larvae and adult lampreys were studied to determine their ability to produce and detect pheromones. Larval gall bladders were removed and gall bladder fluid was extracted and analyzed by high performance liquid chromatography (HPLC). Adult lampreys ability to detect pheromones were tested using electro-olfactogram (EOG) methods. Fifteen compounds including Petromyzonol sulfate (PS), a migratory pheromone found in sea lamprey larvae (Petromyzon marinus) (Li et al. 1995) were tested. Larval lampreys produced large amounts of (PS). Adult Pacific lamprey can detect PS and have an olfactory sensitivity to pheromones that is similar to sea lampreys. iv Pacific lamprey abundance, as indexed by fish ladder counts in 1998, was; Bonneville 37,478; The Dalles 7,665; John Day 12,579; McNary 3,393; Ice Harbor 763; Lower Monumental 69; Little Goose 90; Lower Granite 110; Rock Island 1,410; and Rock Reach 819 dams, respectively. Enumerating Pacific lamprey at counting stations remained extremely problematic, since excessive up- and downstream movement at the counting windows reduces the confidence in fish ladder passage estimates. This may be an indication of passage problems encountered by Pacific lampreys. In-season homing of Pacific lamprey was studied using radio telemetry. Pacific lampery were captured at Willamette Falls and Bonneville Dam, outfitted with radio transmitters and released approximately 26 km downstream of the Willamette River confluence. A total of 50 fish were instrumented. Results will be presented in next year’s report. Natal homing was also investigated using mtDNA analysis of fish captured at Bonneville Dam and from Willamette Falls. These results will also be presented next year. We collected lamprey tissues, from fish captured in several locations throughout the Columbia River Basin, to develop a genetic database for use in determining population structure. Additional samples for populations outside the Columbia River Basin were used to scale the results. Results from this investigation will be presented in next year’s annual report. Since the initiation of the CTUIR lamprey research and restoration project, additional lamprey studies have been proposed that have created uncertainties regarding the prioritization of projects and needs of lampreys. At the request of the Northwest Power Planning Council, a multi-agency Pacific lamprey technical workgroup (TWG) was established in 1996. Annual meetings are held to coordinate projects and prioritize research needs. The TWG identified critical uncertainties and needs to help in determining priorities of ongoing and proposed projects (Appendix A). Finally, an annotated bibliography of relevant lamprey literature was compiled (Appendix B). Close