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• 141. [Article] Developing a predator-prey model for the hake and blue whiting Spanish fisheries

  The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this ...

  Citation × Citation Citation Abstract Copy Title: Developing a predator-prey model for the hake and blue whiting Spanish fisheries Author: Perez-Perez, Marcos, Varela-Lafuente, Manuel, Garza-Gil, Dolores, Torralba-Cano, Julia The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this model, the Southern hake (Merluccius merluccius) represents the predator, and the blue whiting (Micromesistius poutassou) is the prey. Blue whiting is the hake’s main prey in the study area, and it represents about 40% of the Southern hake diet. Both the predator and prey population dynamics follow the Lotka-Volterra formulation, and population dynamics are assumed as logistic, with two interaction coefficients: α is the effect of a unit change in the prey on the percent growth rate of the predator and β is the attack rate or searching efficiency of the predator. The populations interact randomly in proportion to population density. Logistic predator-prey equations were applied to the Southern hake and blue whiting stocks, including biomass, intrinsic rates of growth, carrying capacity and capture for both species. The goal is to maximize the present value of profit, forming the current value Hamiltonian for the maximization problem. Capture costs and prices of hake and blue whiting and discount rate were introduced at this point. Landings and SSB (Spawning Stock Biomass) data from both stocks over the period 1988-2010 were used for an econometric estimation by means of the Ordinary Least Squares method, to determine the form taken by the predator-prey net growth functions. Title: Developing a predator-prey model for the hake and blue whiting Spanish fisheries Author: Perez-Perez, Marcos, Varela-Lafuente, Manuel, Garza-Gil, Dolores, Torralba-Cano, Julia The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this model, the Southern hake (Merluccius merluccius) represents the predator, and the blue whiting (Micromesistius poutassou) is the prey. Blue whiting is the hake’s main prey in the study area, and it represents about 40% of the Southern hake diet. Both the predator and prey population dynamics follow the Lotka-Volterra formulation, and population dynamics are assumed as logistic, with two interaction coefficients: α is the effect of a unit change in the prey on the percent growth rate of the predator and β is the attack rate or searching efficiency of the predator. The populations interact randomly in proportion to population density. Logistic predator-prey equations were applied to the Southern hake and blue whiting stocks, including biomass, intrinsic rates of growth, carrying capacity and capture for both species. The goal is to maximize the present value of profit, forming the current value Hamiltonian for the maximization problem. Capture costs and prices of hake and blue whiting and discount rate were introduced at this point. Landings and SSB (Spawning Stock Biomass) data from both stocks over the period 1988-2010 were used for an econometric estimation by means of the Ordinary Least Squares method, to determine the form taken by the predator-prey net growth functions. Close

• 142. [Article] Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration

  Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory ...

  Citation × Citation Citation Abstract Copy Title: Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration Author: Zamora-Arroyo, Jose Francisco Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to disappear as water was used for agricultural and urban uses in the United States and Mexico. The 1944 United States-Mexico water treaty, which allocates 1.8 million m³/year to Mexico, did not define a minimum flow to maintain the Delta's ecosystems. The resulting degraded Delta lead to the perception in the 1980s that the Delta was a dead ecosystem. This study investigates whether this "dead Delta" perception is valid. Its central hypothesis is that regenerated vegetation in riparian and flood plain zones is associated with surplus river flows during the 1990s. A vegetation analysis, using satellite imagery and field methods, shows that native trees have regenerated during the last 20 years, and now account for 23% of vegetation in a 100 km, non-perennial, stretch of river below the United States-Mexico border. A spatial trend analysis using multi-temporal data on percent vegetation cover indicates that there are 6,320 hectares that show a significant increasing trend (p-value<0.05) in vegetation cover, with the Delta's riparian zone having at least 18% of its area showing this trend. The study estimates that once in four years February to April flow of 300 million m³ (at 80-120 m³/s) is sufficient to germinate and establish new cohorts of native trees, and highlights the need for smaller but more periodic flows in order to maintain wetland areas. It is concluded that there is clear evidence of the resilience of the Delta's ecosystems and that the "dead Delta" perception is no longer valid. There exist critical habitat in the Delta that needs to be protected, while there also exist short and long term opportunities to ecologically enhance and expand current habitat. Hydrological and ecological studies are needed to estimate specific water requirements for these areas in order to efficiently target them for immediate and long term conservation actions. Title: Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration Author: Zamora-Arroyo, Jose Francisco Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to disappear as water was used for agricultural and urban uses in the United States and Mexico. The 1944 United States-Mexico water treaty, which allocates 1.8 million m³/year to Mexico, did not define a minimum flow to maintain the Delta's ecosystems. The resulting degraded Delta lead to the perception in the 1980s that the Delta was a dead ecosystem. This study investigates whether this "dead Delta" perception is valid. Its central hypothesis is that regenerated vegetation in riparian and flood plain zones is associated with surplus river flows during the 1990s. A vegetation analysis, using satellite imagery and field methods, shows that native trees have regenerated during the last 20 years, and now account for 23% of vegetation in a 100 km, non-perennial, stretch of river below the United States-Mexico border. A spatial trend analysis using multi-temporal data on percent vegetation cover indicates that there are 6,320 hectares that show a significant increasing trend (p-value<0.05) in vegetation cover, with the Delta's riparian zone having at least 18% of its area showing this trend. The study estimates that once in four years February to April flow of 300 million m³ (at 80-120 m³/s) is sufficient to germinate and establish new cohorts of native trees, and highlights the need for smaller but more periodic flows in order to maintain wetland areas. It is concluded that there is clear evidence of the resilience of the Delta's ecosystems and that the "dead Delta" perception is no longer valid. There exist critical habitat in the Delta that needs to be protected, while there also exist short and long term opportunities to ecologically enhance and expand current habitat. Hydrological and ecological studies are needed to estimate specific water requirements for these areas in order to efficiently target them for immediate and long term conservation actions. Close

• 143. [Article] Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon

  Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile ...

  Citation × Citation Citation Abstract Copy Title: Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon Author: Mackereth, Kailan F. Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations (e.g., installation of tide gates, construction of dikes, channelization) to increase the net area of land suitable for agriculture and development resulting in watershed fragmentation and reduction in the amount of habitats with high intrinsic potential to support populations of juvenile salmonids. Until recent years, sub-yearling coho salmon found in lowland riverine habitats and estuarine marshes were assumed to have been displaced from optimal upland reaches by competition and high water discharge. Recent studies have concluded that early estuarine migrant behavior is volitional and these fish return as 20-40% of the spawning population, but there are few studies that delve into the capacity of estuarine habitat to support early estuarine life history strategies in systems heavily altered by human practices. This study documented differences in diet and condition factor (K) between sub-yearling and yearling coho salmon foraging concurrently in brackish or freshwater lowland habitat of the upper estuarine intertidal zone. Fish stomach contents were sampled by means of gastric lavage in three coastal lowland creeks in Coos Bay on the southern Oregon coast. Prey found in the samples were sorted, counted, identified, and dried to obtain dry weight biomass. Condition factor (K) and total dry weight prey biomass of fishes were not different between brackish and freshwater habitat; however, non-metric multidimensional scaling indicated that prey composition was substantially different between habitat and age class. These findings suggest that early migrating sub-yearlings and yearling smolts diverge in their diets whether they occupy the same or different habitats in the stream to estuary transition zone. Insects were important prey within the diets of yearling and sub-yearling freshwater foragers and sub-yearling brackish water foragers while crustaceans were important in the diets of yearling brackish water foragers. Future research exploring prey abundance and availability in relation to prey selected by juvenile coho salmon would denote habitat foraging quality and habitat exploitation by early estuarine migrants. Expanding this research to contrast natural intertidal habitats with those regulated by tide gates would be beneficial towards understanding the impact different styles of tide gates have on biotic communities and hydrological attributes (e.g., flow, chemistry, temperature, tidal exchange). Identification of factors that influence habitat selection in the stream-estuary ecotone by alternative early life history strategies of juvenile coho salmon is essential towards enhancing genetic diversity thereby strengthening the resiliency of the population. Title: Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon Author: Mackereth, Kailan F. Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations (e.g., installation of tide gates, construction of dikes, channelization) to increase the net area of land suitable for agriculture and development resulting in watershed fragmentation and reduction in the amount of habitats with high intrinsic potential to support populations of juvenile salmonids. Until recent years, sub-yearling coho salmon found in lowland riverine habitats and estuarine marshes were assumed to have been displaced from optimal upland reaches by competition and high water discharge. Recent studies have concluded that early estuarine migrant behavior is volitional and these fish return as 20-40% of the spawning population, but there are few studies that delve into the capacity of estuarine habitat to support early estuarine life history strategies in systems heavily altered by human practices. This study documented differences in diet and condition factor (K) between sub-yearling and yearling coho salmon foraging concurrently in brackish or freshwater lowland habitat of the upper estuarine intertidal zone. Fish stomach contents were sampled by means of gastric lavage in three coastal lowland creeks in Coos Bay on the southern Oregon coast. Prey found in the samples were sorted, counted, identified, and dried to obtain dry weight biomass. Condition factor (K) and total dry weight prey biomass of fishes were not different between brackish and freshwater habitat; however, non-metric multidimensional scaling indicated that prey composition was substantially different between habitat and age class. These findings suggest that early migrating sub-yearlings and yearling smolts diverge in their diets whether they occupy the same or different habitats in the stream to estuary transition zone. Insects were important prey within the diets of yearling and sub-yearling freshwater foragers and sub-yearling brackish water foragers while crustaceans were important in the diets of yearling brackish water foragers. Future research exploring prey abundance and availability in relation to prey selected by juvenile coho salmon would denote habitat foraging quality and habitat exploitation by early estuarine migrants. Expanding this research to contrast natural intertidal habitats with those regulated by tide gates would be beneficial towards understanding the impact different styles of tide gates have on biotic communities and hydrological attributes (e.g., flow, chemistry, temperature, tidal exchange). Identification of factors that influence habitat selection in the stream-estuary ecotone by alternative early life history strategies of juvenile coho salmon is essential towards enhancing genetic diversity thereby strengthening the resiliency of the population. Close

• 144. [Article] Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries

  Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident ...

  Citation × Citation Citation Abstract Copy Title: Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident forms. The factors contributing to life history variation within populations are not well understood, but probably are not strictly genetic (e.g. Johnson et al, in review). Variation in migration tendency within cutthroat populations may result from phenotype plasticity, influenced by density, frequency, or condition dependent processes (Hendry et al. 2004). For example, an individual cutthroat’s choice to migrate at a given time or age may be a response to environmental conditions mediated by a genetically determined reaction norm (Hutchings 2004). This report summarizes a study undertaken to describe the expression of migratory behavior within coastal cutthroat trout populations, the relationship among migratory and non-migratory individuals, and the implications of life history diversity for management of cutthroat trout in tributaries of the lower Columbia River. The relationship between resident and migratory populations (or resident and migratory individuals within populations) is of central importance for management of coastal cutthroat trout. In the lower Columbia River and southwest Washington State a proposed rule to list anadromous cutthroat as threatened under the federal Endangered Species Act (ESA) was withdrawn after the US Fish and Wildlife Service (USFWS) decided during its review process to include resident and anadromous forms in the same Distinct Population Segment (DPS). Debate over proposed ESA listing highlighted a general lack of knowledge about coastal cutthroat trout life history, relationships between resident and migratory forms, and estuarine habitat use in the lower Columbia River. In 2009, the decision not to list the DPS as threatened was remanded to the USFWS on the grounds that the Service had not adequately considered whether marine and estuarine habitats formed a significant portion of the range of the DPS (USFWS 2009). We evaluated the distribution and abundance of coastal cutthroat trout in Big Creek and Bear Creek, two tributaries that join the Columbia River estuary from the south (Oregon) side roughly 30 kilometers from the ocean, and monitored the migratory behavior of cutthroat that emigrated from these streams and entered the Columbia River estuary. Big Creek is an interesting system because a fish weir and diversion dam at an ODFW hatchery, established in 1941 and refurbished in 1957, prevent cutthroat trout from passing upstream, isolating the cutthroat spawning population above the hatchery. Despite this barrier to upstream migration, offspring of resident cutthroat in the upper watershed continue to “smolt” and migrate downstream past the barrier. We were interested in the fate of these fish and their contribution to the adult population. Bear Creek, on the other hand, has always had full access for anadromous cutthroat through much of its drainage. These two systems permit a comparison of life history characteristics, migration, and survival of coastal cutthroat rearing in streams above and below migration barriers, and provide study sites in Oregon to compliment research by USFWS of coastal cutthroat migration behavior in tributaries entering the estuary from the north side of the Columbia River (USFWS 2008; and see Hudson et al. 2008; Johnson 2008; Zydlewski et al. 2008). A major objective of our work in Big Creek and Bear Creek was to increase understanding of coastal cutthroat trout biology and the relationship between resident and migratory cutthroat in lower Columbia tributaries. Additionally, we sought to document habitat use in the Columbia River estuary by migrant cutthroat. Our specific objectives were to: • Estimate abundance of coastal cutthroat trout in Big Creek (above hatchery barrier) and Bear Creek (above and below a large dam) • Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration • Describe habitats used by anadromous migrants and characterize migration behavior within the Columbia River estuary • Measure estuarine/marine survival of anadromous individuals and document return to natal streams Title: Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident forms. The factors contributing to life history variation within populations are not well understood, but probably are not strictly genetic (e.g. Johnson et al, in review). Variation in migration tendency within cutthroat populations may result from phenotype plasticity, influenced by density, frequency, or condition dependent processes (Hendry et al. 2004). For example, an individual cutthroat’s choice to migrate at a given time or age may be a response to environmental conditions mediated by a genetically determined reaction norm (Hutchings 2004). This report summarizes a study undertaken to describe the expression of migratory behavior within coastal cutthroat trout populations, the relationship among migratory and non-migratory individuals, and the implications of life history diversity for management of cutthroat trout in tributaries of the lower Columbia River. The relationship between resident and migratory populations (or resident and migratory individuals within populations) is of central importance for management of coastal cutthroat trout. In the lower Columbia River and southwest Washington State a proposed rule to list anadromous cutthroat as threatened under the federal Endangered Species Act (ESA) was withdrawn after the US Fish and Wildlife Service (USFWS) decided during its review process to include resident and anadromous forms in the same Distinct Population Segment (DPS). Debate over proposed ESA listing highlighted a general lack of knowledge about coastal cutthroat trout life history, relationships between resident and migratory forms, and estuarine habitat use in the lower Columbia River. In 2009, the decision not to list the DPS as threatened was remanded to the USFWS on the grounds that the Service had not adequately considered whether marine and estuarine habitats formed a significant portion of the range of the DPS (USFWS 2009). We evaluated the distribution and abundance of coastal cutthroat trout in Big Creek and Bear Creek, two tributaries that join the Columbia River estuary from the south (Oregon) side roughly 30 kilometers from the ocean, and monitored the migratory behavior of cutthroat that emigrated from these streams and entered the Columbia River estuary. Big Creek is an interesting system because a fish weir and diversion dam at an ODFW hatchery, established in 1941 and refurbished in 1957, prevent cutthroat trout from passing upstream, isolating the cutthroat spawning population above the hatchery. Despite this barrier to upstream migration, offspring of resident cutthroat in the upper watershed continue to “smolt” and migrate downstream past the barrier. We were interested in the fate of these fish and their contribution to the adult population. Bear Creek, on the other hand, has always had full access for anadromous cutthroat through much of its drainage. These two systems permit a comparison of life history characteristics, migration, and survival of coastal cutthroat rearing in streams above and below migration barriers, and provide study sites in Oregon to compliment research by USFWS of coastal cutthroat migration behavior in tributaries entering the estuary from the north side of the Columbia River (USFWS 2008; and see Hudson et al. 2008; Johnson 2008; Zydlewski et al. 2008). A major objective of our work in Big Creek and Bear Creek was to increase understanding of coastal cutthroat trout biology and the relationship between resident and migratory cutthroat in lower Columbia tributaries. Additionally, we sought to document habitat use in the Columbia River estuary by migrant cutthroat. Our specific objectives were to: • Estimate abundance of coastal cutthroat trout in Big Creek (above hatchery barrier) and Bear Creek (above and below a large dam) • Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration • Describe habitats used by anadromous migrants and characterize migration behavior within the Columbia River estuary • Measure estuarine/marine survival of anadromous individuals and document return to natal streams Close

• 145. [Image] Progress report for investigations on Blue Creek, fiscal year 1992, Blue Creek, California

  	PROGRESS REPORT FOR INVESTIGATIONS ON BLUE CREEK FT 1992 ABSTRACT The U.S. Fish and Wildlife Service, Coastal California Fishery Resource Office in Arcata, California, was funded to investigate chinook ...
  	Citation × Citation Citation Abstract Copy Title: Progress report for investigations on Blue Creek, fiscal year 1992, Blue Creek, California Author: Chan, Jeffrey R. ; Longenbaugh, Matthew H. Year: 1994, 2005 PROGRESS REPORT FOR INVESTIGATIONS ON BLUE CREEK FT 1992 ABSTRACT The U.S. Fish and Wildlife Service, Coastal California Fishery Resource Office in Arcata, California, was funded to investigate chinook salmon roncorhvnchus tshawvtschav spavming use, juvenile salmonid emigration, and characterize stream habitats in Blue Creek, a tributary to' the Klamath River; California. Investigations began in October 1988, with this reporting period covering October 1991 through September 1992. Adult chinook spawner escapement was addressed by surveys of redds, live fish and carcasses, and by radioteleiretry. Spawner numbers were v?ry low, with only 22 redds observed in fall 1991/winter 1992. The peak count of adult Chinook was 97 fish in early November. Radiotelemetry of migrating spawners (n?8) was used to locate remote spawning areas. Emigrating juvenile Chinook salmon, steelhead trout 10. mvkissV/ coho salmon (fi. kisutchl. and coastal cutthroat trout (g. clarltiV were trapped at river kilometer (rkm) 3.35 with a rotary screw trap (screw trap). The trapping period extended from April to July for a total of 75 trapping nights. Screw trap catches totaled 10,688 chinook, 1,388 steelhead, 99 coho and 10 cutthroat. Peak Chinook emigration occurred during the week of May 17, which is consistent with the past 3 years of monitoring. A juvenile weir was operated 58 nights, and caught a total of 9,166 chinook, 1,196 steelhead, 127 coho and 1 cutthroat. The index of abundance for emigrating chinook during the 1992 juvenile trapping period was 49,590. Sixty-five percent of the juvenile chinook caught during the trapping season were marked with coded wire tags (n-12,687) and released back into Blue Creek at rkm 3.3. Mean water temperatures varied from 6.3 to 18.6 XI and stream flows ranged from 43 to 2178 eft (1.3 to 61.7 m3/?) during the Fiscal Year (FY) 1992 study season. Title: Progress report for investigations on Blue Creek, fiscal year 1992, Blue Creek, California Author: Chan, Jeffrey R. ; Longenbaugh, Matthew H. Year: 1994, 2005 PROGRESS REPORT FOR INVESTIGATIONS ON BLUE CREEK FT 1992 ABSTRACT The U.S. Fish and Wildlife Service, Coastal California Fishery Resource Office in Arcata, California, was funded to investigate chinook salmon roncorhvnchus tshawvtschav spavming use, juvenile salmonid emigration, and characterize stream habitats in Blue Creek, a tributary to' the Klamath River; California. Investigations began in October 1988, with this reporting period covering October 1991 through September 1992. Adult chinook spawner escapement was addressed by surveys of redds, live fish and carcasses, and by radioteleiretry. Spawner numbers were v?ry low, with only 22 redds observed in fall 1991/winter 1992. The peak count of adult Chinook was 97 fish in early November. Radiotelemetry of migrating spawners (n?8) was used to locate remote spawning areas. Emigrating juvenile Chinook salmon, steelhead trout 10. mvkissV/ coho salmon (fi. kisutchl. and coastal cutthroat trout (g. clarltiV were trapped at river kilometer (rkm) 3.35 with a rotary screw trap (screw trap). The trapping period extended from April to July for a total of 75 trapping nights. Screw trap catches totaled 10,688 chinook, 1,388 steelhead, 99 coho and 10 cutthroat. Peak Chinook emigration occurred during the week of May 17, which is consistent with the past 3 years of monitoring. A juvenile weir was operated 58 nights, and caught a total of 9,166 chinook, 1,196 steelhead, 127 coho and 1 cutthroat. The index of abundance for emigrating chinook during the 1992 juvenile trapping period was 49,590. Sixty-five percent of the juvenile chinook caught during the trapping season were marked with coded wire tags (n-12,687) and released back into Blue Creek at rkm 3.3. Mean water temperatures varied from 6.3 to 18.6 XI and stream flows ranged from 43 to 2178 eft (1.3 to 61.7 m3/?) during the Fiscal Year (FY) 1992 study season. Close

• 146. [Image] Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp

  	"April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66)
  	Citation × Citation Citation Abstract Copy Title: Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp Author: U.S. Fish and Wildlife Service. Oregon State Office Year: 1998, 2004 "April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66) Title: Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp Author: U.S. Fish and Wildlife Service. Oregon State Office Year: 1998, 2004 "April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66) Close

• 147. [Article] Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta

  The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late ...

  Citation × Citation Citation Abstract Copy Title: Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta Author: Maggiulli, Nicole Marie The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late 1970s. In an effort to alleviate mammalian predation, increase nest success, and avoid a listing under the U.S. Endangered Species Act, an artificial nest island (island) program was implemented on the western CRD in 1983. The installation of new islands on the CRD is the sole management action of the Pacific Flyway Council on the breeding grounds, but no comprehensive evaluation of the program has been published. I examined general trends in island use and nest success over time for three island types (donut islands, fiberglass floater islands, and sandbag islands) from 1984-2005. I used data from the island program to identify factors associated with dusky Canada goose nesting (hereafter, use) and nest success on islands from 1996-2005. I generated a series of candidate models and used logistic regression with model selection techniques to determine how variables representing pond characteristics, vegetative characteristics, interactions with conspecifics and larid species, the previous year’s island status, and the distance to predator corridors were associated with island use and nest success for each year. Use of islands by dusky geese nesting on the western CRD increased between 1987 and 2005 from a low of 10% in 1987 to 44% in 2005. There was annual variability in factors associated with island use; however, use of islands was most consistently and strongly associated with the previous year’s island status. The odds of a nest being placed on an island that contained a successful nest the previous year were 2.91 to 6.62 times greater than for islands not used the previous year. There was also evidence for an increased likelihood of island use further from shore and for islands with up to 55% aerial shrub cover and shrubs up to 1 m tall. Nest success was consistently high, indicating islands have long term potential for increasing dusky goose nest success on the Copper River Delta. Compared to island use, my analysis of nest success and habitat features resulted in many more competitive models (average 10 v. 2 per year) with fewer strong (95% confidence intervals for parameter estimates excluded zero) associations between explanatory variables and nest success. Explanatory variables representing vegetative characteristics, interactions with conspecifics and larid species, and the distance to predator corridors had a relatively low capacity to explain nest success on artificial islands. However, there was some evidence for an increased likelihood of nest success on islands further from shore with shorter shrubs. Lower variability in factors associated with island use is likely because factors associated with nest site selection are controlled by decisions of the nesting goose. The importance of previous year’s island status on island use likely reflects high site fidelity by breeding adult geese, with fidelity being higher for birds that have successful nests. Alternately, dusky geese use cues from the previous year’s nesting activity when prospecting for island nest sites. In contrast, nest success is dependent on a more complex combination of factors that vary within and among years outside the control of a nesting goose. Inter-annual variation in the timing and magnitude of eulachon (Thaleichthys pacificus) spawning runs on large sloughs of the CRD and prey-switching by important dusky goose nest predators may have considerable influence on dusky goose nest success on islands, similar to mainland- nesting dusky geese. The inability to control for eulachon presence and abundance may have confounded my analysis of habitat features important to nest success. Therefore, factors such as presence of alternate prey (and predator abundance) may be more important to dusky goose nest success on islands than habitat features. Current use of available nest islands is at a program high of 44% and nest success also remains high (63%); suggesting the artificial nest island program is valuable for dusky geese. However, the contribution of island-nesting dusky geese to the dusky goose population on the Copper River Delta is unclear. There is a need for a population model that incorporates all recent information on dusky goose reproductive ecology to determine if artificial nest islands can increase dusky goose population size, and if so, how many islands are needed. Title: Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta Author: Maggiulli, Nicole Marie The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late 1970s. In an effort to alleviate mammalian predation, increase nest success, and avoid a listing under the U.S. Endangered Species Act, an artificial nest island (island) program was implemented on the western CRD in 1983. The installation of new islands on the CRD is the sole management action of the Pacific Flyway Council on the breeding grounds, but no comprehensive evaluation of the program has been published. I examined general trends in island use and nest success over time for three island types (donut islands, fiberglass floater islands, and sandbag islands) from 1984-2005. I used data from the island program to identify factors associated with dusky Canada goose nesting (hereafter, use) and nest success on islands from 1996-2005. I generated a series of candidate models and used logistic regression with model selection techniques to determine how variables representing pond characteristics, vegetative characteristics, interactions with conspecifics and larid species, the previous year’s island status, and the distance to predator corridors were associated with island use and nest success for each year. Use of islands by dusky geese nesting on the western CRD increased between 1987 and 2005 from a low of 10% in 1987 to 44% in 2005. There was annual variability in factors associated with island use; however, use of islands was most consistently and strongly associated with the previous year’s island status. The odds of a nest being placed on an island that contained a successful nest the previous year were 2.91 to 6.62 times greater than for islands not used the previous year. There was also evidence for an increased likelihood of island use further from shore and for islands with up to 55% aerial shrub cover and shrubs up to 1 m tall. Nest success was consistently high, indicating islands have long term potential for increasing dusky goose nest success on the Copper River Delta. Compared to island use, my analysis of nest success and habitat features resulted in many more competitive models (average 10 v. 2 per year) with fewer strong (95% confidence intervals for parameter estimates excluded zero) associations between explanatory variables and nest success. Explanatory variables representing vegetative characteristics, interactions with conspecifics and larid species, and the distance to predator corridors had a relatively low capacity to explain nest success on artificial islands. However, there was some evidence for an increased likelihood of nest success on islands further from shore with shorter shrubs. Lower variability in factors associated with island use is likely because factors associated with nest site selection are controlled by decisions of the nesting goose. The importance of previous year’s island status on island use likely reflects high site fidelity by breeding adult geese, with fidelity being higher for birds that have successful nests. Alternately, dusky geese use cues from the previous year’s nesting activity when prospecting for island nest sites. In contrast, nest success is dependent on a more complex combination of factors that vary within and among years outside the control of a nesting goose. Inter-annual variation in the timing and magnitude of eulachon (Thaleichthys pacificus) spawning runs on large sloughs of the CRD and prey-switching by important dusky goose nest predators may have considerable influence on dusky goose nest success on islands, similar to mainland- nesting dusky geese. The inability to control for eulachon presence and abundance may have confounded my analysis of habitat features important to nest success. Therefore, factors such as presence of alternate prey (and predator abundance) may be more important to dusky goose nest success on islands than habitat features. Current use of available nest islands is at a program high of 44% and nest success also remains high (63%); suggesting the artificial nest island program is valuable for dusky geese. However, the contribution of island-nesting dusky geese to the dusky goose population on the Copper River Delta is unclear. There is a need for a population model that incorporates all recent information on dusky goose reproductive ecology to determine if artificial nest islands can increase dusky goose population size, and if so, how many islands are needed. Close

• 148. [Image] Trinity River Flow Evaluation: final report: a report to the Secretary , U.S. Department of the Interior

  	TRINITY RIVER FLOW EVALUATION - FINAL REPORT EXECUTIVE SUMMARY When Congress authorized construction of the Trinity River Division (TRD) of the Central Valley Project (CVP) in 1955, the expectation was ...
  	Citation × Citation Citation Abstract Copy Title: Trinity River Flow Evaluation: final report: a report to the Secretary , U.S. Department of the Interior Author: U.S. Fish and Wildlife Service; Arcata Fish and Wildlife Office; Hoopa Valley Tribe Year: 1999, 2006, 2005 TRINITY RIVER FLOW EVALUATION - FINAL REPORT EXECUTIVE SUMMARY When Congress authorized construction of the Trinity River Division (TRD) of the Central Valley Project (CVP) in 1955, the expectation was that surplus water could be exported to the Central Valley without harm to the fish and wildlife resources of the Trinity River. The TRD began operations in 1963, diverting up to 90 percent of the Trinity River's average annual yield at Lewiston, California. Access to 109 river miles of fish habitat and replenishment of coarse sediment from upstream river segments were permanently eliminated by Lewiston and Trinity Dams. Within a decade of completing the TRD, the adverse biological and geomorphic responses to TRD operations were obvious. Riverine habitats below Lewiston Dam degraded and salmon and steelhead populations noticeably declined. In 1981, the Secretary of the Interior (Secretary) directed that a Trinity River Flow Evaluation (TRFE) study be conducted to determine how to rest Title: Trinity River Flow Evaluation: final report: a report to the Secretary , U.S. Department of the Interior Author: U.S. Fish and Wildlife Service; Arcata Fish and Wildlife Office; Hoopa Valley Tribe Year: 1999, 2006, 2005 TRINITY RIVER FLOW EVALUATION - FINAL REPORT EXECUTIVE SUMMARY When Congress authorized construction of the Trinity River Division (TRD) of the Central Valley Project (CVP) in 1955, the expectation was that surplus water could be exported to the Central Valley without harm to the fish and wildlife resources of the Trinity River. The TRD began operations in 1963, diverting up to 90 percent of the Trinity River's average annual yield at Lewiston, California. Access to 109 river miles of fish habitat and replenishment of coarse sediment from upstream river segments were permanently eliminated by Lewiston and Trinity Dams. Within a decade of completing the TRD, the adverse biological and geomorphic responses to TRD operations were obvious. Riverine habitats below Lewiston Dam degraded and salmon and steelhead populations noticeably declined. In 1981, the Secretary of the Interior (Secretary) directed that a Trinity River Flow Evaluation (TRFE) study be conducted to determine how to rest Close

• 149. [Image] Summary of ongoing and planned work of the Department of the Interior related to the Klamath River Basin, March 2003

  	The Department of the Interior, Klamath River Basin, Work Plans and Reports
  	Citation × Citation Citation Abstract Copy Title: Summary of ongoing and planned work of the Department of the Interior related to the Klamath River Basin, March 2003 Author: United States. Dept. of the Interior Year: 2003, 2005 The Department of the Interior, Klamath River Basin, Work Plans and Reports Title: Summary of ongoing and planned work of the Department of the Interior related to the Klamath River Basin, March 2003 Author: United States. Dept. of the Interior Year: 2003, 2005 The Department of the Interior, Klamath River Basin, Work Plans and Reports Close

• 150. [Image] Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker

  	BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath ...
  	Citation × Citation Citation Abstract Copy Title: Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker Author: United States. Bureau of Reclamation Year: 2001, 2005 BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath Falls, Oregon February 13,2001 TABLE OF CONTENTS 1.0 INTRODUCTION 2 2.0 DESCRIPTION OF THE ACTION 3 3.0 DESCRIPTION OF HISTORIC OPERATIONS 6 4.0 ENDANGERED SPECIES POTENTIALLY AFFECTED BY THE KLAMATH PROJECT 16 5.0 ENVIRONMENTAL BASELINE 60 6.0 EFFECTS OF KLAMATH PROJECT ON BALD EAGLES 60 7.0 EFFECTS OF KLAMATH PROJECT ENDANGERED SUCKERS 63 8.0 PROPOSED CRITICAL HABITAT FOR ENDANGERED SUCKERS 82 9.0 CUMULATIVE EFFECTS 84 10.0 DETERMINATION OF EFFECTS 89 11.0 LITERATURE CITED 90 12.0 PERSONAL COMMUNICATIONS 100 13.0 APPENDIX 1 - ESA CONSULTATION REVIEW 101 Title: Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker Author: United States. Bureau of Reclamation Year: 2001, 2005 BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath Falls, Oregon February 13,2001 TABLE OF CONTENTS 1.0 INTRODUCTION 2 2.0 DESCRIPTION OF THE ACTION 3 3.0 DESCRIPTION OF HISTORIC OPERATIONS 6 4.0 ENDANGERED SPECIES POTENTIALLY AFFECTED BY THE KLAMATH PROJECT 16 5.0 ENVIRONMENTAL BASELINE 60 6.0 EFFECTS OF KLAMATH PROJECT ON BALD EAGLES 60 7.0 EFFECTS OF KLAMATH PROJECT ENDANGERED SUCKERS 63 8.0 PROPOSED CRITICAL HABITAT FOR ENDANGERED SUCKERS 82 9.0 CUMULATIVE EFFECTS 84 10.0 DETERMINATION OF EFFECTS 89 11.0 LITERATURE CITED 90 12.0 PERSONAL COMMUNICATIONS 100 13.0 APPENDIX 1 - ESA CONSULTATION REVIEW 101 Close