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• 1. [Article] Nesting ecology of mallards in the Willamette Valley of Oregon

  Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I ...

  Citation × Citation Citation Abstract Copy Title: Nesting ecology of mallards in the Willamette Valley of Oregon Author: Rickerson, Eric V. Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting and nesting phases, nesting cover selection, nesting and female success rates, nesting chronology, and survival of females during the pre-nesting and nesting periods. Wetland habitat selection was higher for seasonal riverine and permanent lacustrine habitats during the pre-nesting and nesting periods. Uncultivated upland and wetland habitat nesting sites with a strong cover component had a higher selection ranking compared to agricultural cropland and ash-cottonwood riparian. The reproductive period was 107 days beginning in early-March and concluding in late-June with the peak of nest attempts occurring around May 9. Nesting effort was low with 38.4% of females failing to attempts at least one nest. Nest survival probabilities ranged from 0.106 in 1995 to 0.216 in 1996 with a pooled estimate of 0.186 (95% C.I.=0.122-0.298). Mammalian predation accounted for 84% of nest failures. Overall female success was 40.5% and differed between first year (SY) and second year and older females (ASY). Female survival probabilities ranged from 0.5 11 in 1995 to 0.733 in 1996, with a pooled estimate of 0.668 (95% C.I.=0.5370.842). Title: Nesting ecology of mallards in the Willamette Valley of Oregon Author: Rickerson, Eric V. Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting and nesting phases, nesting cover selection, nesting and female success rates, nesting chronology, and survival of females during the pre-nesting and nesting periods. Wetland habitat selection was higher for seasonal riverine and permanent lacustrine habitats during the pre-nesting and nesting periods. Uncultivated upland and wetland habitat nesting sites with a strong cover component had a higher selection ranking compared to agricultural cropland and ash-cottonwood riparian. The reproductive period was 107 days beginning in early-March and concluding in late-June with the peak of nest attempts occurring around May 9. Nesting effort was low with 38.4% of females failing to attempts at least one nest. Nest survival probabilities ranged from 0.106 in 1995 to 0.216 in 1996 with a pooled estimate of 0.186 (95% C.I.=0.122-0.298). Mammalian predation accounted for 84% of nest failures. Overall female success was 40.5% and differed between first year (SY) and second year and older females (ASY). Female survival probabilities ranged from 0.5 11 in 1995 to 0.733 in 1996, with a pooled estimate of 0.668 (95% C.I.=0.5370.842). Close

• 2. [Article] Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement

  Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. ...

  Citation × Citation Citation Abstract Copy Title: Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement Author: Henning, Julie A. Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. As a result, restoration and enhancement projects to remediate for the loss of such wetland habitat are being implemented for waterfowl and other wildlife with little consideration for fishes such as juvenile salmon (Oncorhynchus spp.). The objectives of this study were to examine the degree to which fish utilize emergent wetlands and to determine the influence of wetland enhancement on fish communities in the Chehalis River floodplain. Furthermore, I quantified the influence of enhanced wetlands on juvenile coho salmon. A minimum of 18 fish species utilized floodplain wetlands, and the most abundant were three-spine stickleback (Gasterosteus aculeatus) and Olympic mudminnow (Novumbra hubbsi). Both enhanced and unenhanced emergent wetlands had higher abundances of nongame native fishes than oxbow habitats. Coho salmon (Oncorhynchus kisutch) was the dominant salmonid at all sites and enhanced wetlands had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and were near lethal limits for juvenile salmon by June each year. Survival of fishes utilizing emergent wetlands was dependent on movement to the river before water quality decreased and/or the wetland became isolated and stranding occurred. Emigration patterns suggested that coho salmon yearling and young-of-the-year emigrated as habitat conditions declined. This was further supported by the results of the experimental release of yearling coho salmon. Yearling coho salmon benefited from rearing in enhanced wetland habitats where their growth and survival were comparable to studies of juvenile coho off-channel habitats. Title: Floodplain emergent wetlands as rearing habitat for fishes and the implications for wetland enhancement Author: Henning, Julie A. Seasonal emergent wetlands in the Pacific Northwest have not been regarded traditionally as fish rearing habitat, despite access to such habitat when river flows overtop riverbanks and connect to the floodplain. As a result, restoration and enhancement projects to remediate for the loss of such wetland habitat are being implemented for waterfowl and other wildlife with little consideration for fishes such as juvenile salmon (Oncorhynchus spp.). The objectives of this study were to examine the degree to which fish utilize emergent wetlands and to determine the influence of wetland enhancement on fish communities in the Chehalis River floodplain. Furthermore, I quantified the influence of enhanced wetlands on juvenile coho salmon. A minimum of 18 fish species utilized floodplain wetlands, and the most abundant were three-spine stickleback (Gasterosteus aculeatus) and Olympic mudminnow (Novumbra hubbsi). Both enhanced and unenhanced emergent wetlands had higher abundances of nongame native fishes than oxbow habitats. Coho salmon (Oncorhynchus kisutch) was the dominant salmonid at all sites and enhanced wetlands had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and were near lethal limits for juvenile salmon by June each year. Survival of fishes utilizing emergent wetlands was dependent on movement to the river before water quality decreased and/or the wetland became isolated and stranding occurred. Emigration patterns suggested that coho salmon yearling and young-of-the-year emigrated as habitat conditions declined. This was further supported by the results of the experimental release of yearling coho salmon. Yearling coho salmon benefited from rearing in enhanced wetland habitats where their growth and survival were comparable to studies of juvenile coho off-channel habitats. Close

• 3. [Article] Lower Middle Fork Willamette River Watershed Assessment

  Abstract -- This watershed assessment includes the following topics: land forms and geology, land ownership and uses, hydrology, riparian habitat conditions, aquatic habitat and fish populations, wetland ...

  Citation × Citation Citation Abstract Copy Title: Lower Middle Fork Willamette River Watershed Assessment Abstract -- This watershed assessment includes the following topics: land forms and geology, land ownership and uses, hydrology, riparian habitat conditions, aquatic habitat and fish populations, wetland habitat conditions, water quality, and sediment sources. Title: Lower Middle Fork Willamette River Watershed Assessment Abstract -- This watershed assessment includes the following topics: land forms and geology, land ownership and uses, hydrology, riparian habitat conditions, aquatic habitat and fish populations, wetland habitat conditions, water quality, and sediment sources. Close

• 4. [Article] Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands

  Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. ...

  Citation × Citation Citation Abstract Copy Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Close

• 5. [Article] Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991

  The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study ...

  Citation × Citation Citation Abstract Copy Title: Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991 Author: Allen, Tracy Hunter The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study quantifies the areal extent and degree of wetlands change and associated causes along the LCR over the past 44 years. This research examines the distribution of wetland types and their patterns of change, developing regional models which rank areas most conducive to potential wetland recovery or restoration efforts. The length of the study area totals 234 river kilometers, from the mouth of the Columbia River to Bonneville Dam. The width includes the active channel and an approximately three-kilometer swath on either side of the river. Aerial photography was the primary means for interpreting historical extent of wetlands, using five photo dates (1948, 1961, 1973, 1983, and 1991), based upon their time interval, coverage, and photo quality. For each photo throughout the entire study site, land uses and wetland habitats greater than one hectare were identified and classified. Each classified polygon was digitized and spatially analyzed using a Geographic Information System. This study indicates that wetland habitats which were once contiguously draped upon the linear features of the river are decreasing in size and becoming fragmented. There have been both increases and decreases in specific wetland habitat areas which vary by river reach, even though wetlands have diminished overall. The estuarine section of the LCR experienced a 25% net decrease in wetland area between 1948 and 1991, while the riverine tidal section fostered a 1% increase. The riverine lower perennial section sustained the greatest loss of wetlands, which decreased by 37%. Causes for wetland losses in the estuarine section were largely related to in-water activities, such as channelization, while the causes for declines in the riverine lower perennial section were correlated with rapid urbanization. Wetland increases in the riverine tidal section were generally influenced by significant growth in palustrine and forested wetlands associated with the establishment of wildlife refuges and the incremental increase of upstream flood storage capacity. This research provides a template for identifying degraded or displaced wetlands. Through the use of a GIS, each historical wetland was ranked in either low, moderate, or high categories for restoration potential. GIS technology permits focused, sequentially-refined queries to identify potential restoration or recovery sites. In the estuarine section, 74 historical wetland sites were ranked high for restoration potential, while in the riverine tidal and riverine lower perennial sections, there were 178 and 105, respectively. Overall, these sites represent only 25% of the area occupied by wetlands in 1948. While this study advocates restoration potential, restoration is not a surrogate for responsible ecosystem-wide stewardship of the riparian zone. Restoration will not succeed unless degrading factors are mitigated or eliminated. Title: Areal distribution, change, and restoration potential of wetlands within the lower Columbia River riparian zone, 1948-1991 Author: Allen, Tracy Hunter The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study quantifies the areal extent and degree of wetlands change and associated causes along the LCR over the past 44 years. This research examines the distribution of wetland types and their patterns of change, developing regional models which rank areas most conducive to potential wetland recovery or restoration efforts. The length of the study area totals 234 river kilometers, from the mouth of the Columbia River to Bonneville Dam. The width includes the active channel and an approximately three-kilometer swath on either side of the river. Aerial photography was the primary means for interpreting historical extent of wetlands, using five photo dates (1948, 1961, 1973, 1983, and 1991), based upon their time interval, coverage, and photo quality. For each photo throughout the entire study site, land uses and wetland habitats greater than one hectare were identified and classified. Each classified polygon was digitized and spatially analyzed using a Geographic Information System. This study indicates that wetland habitats which were once contiguously draped upon the linear features of the river are decreasing in size and becoming fragmented. There have been both increases and decreases in specific wetland habitat areas which vary by river reach, even though wetlands have diminished overall. The estuarine section of the LCR experienced a 25% net decrease in wetland area between 1948 and 1991, while the riverine tidal section fostered a 1% increase. The riverine lower perennial section sustained the greatest loss of wetlands, which decreased by 37%. Causes for wetland losses in the estuarine section were largely related to in-water activities, such as channelization, while the causes for declines in the riverine lower perennial section were correlated with rapid urbanization. Wetland increases in the riverine tidal section were generally influenced by significant growth in palustrine and forested wetlands associated with the establishment of wildlife refuges and the incremental increase of upstream flood storage capacity. This research provides a template for identifying degraded or displaced wetlands. Through the use of a GIS, each historical wetland was ranked in either low, moderate, or high categories for restoration potential. GIS technology permits focused, sequentially-refined queries to identify potential restoration or recovery sites. In the estuarine section, 74 historical wetland sites were ranked high for restoration potential, while in the riverine tidal and riverine lower perennial sections, there were 178 and 105, respectively. Overall, these sites represent only 25% of the area occupied by wetlands in 1948. While this study advocates restoration potential, restoration is not a surrogate for responsible ecosystem-wide stewardship of the riparian zone. Restoration will not succeed unless degrading factors are mitigated or eliminated. Close

• 6. [Article] Influence of Wetland Landscape Structure on Duck Nest Success at Malheur National Wildlife Refuge, Oregon

  The decline of waterfowl populations and their requisite wetland habitats remains a concern. Because migratory bird refuges are often artificial landscapes of actively managed wetlands, and wildlife populations ...

  Citation × Citation Citation Abstract Copy Title: Influence of Wetland Landscape Structure on Duck Nest Success at Malheur National Wildlife Refuge, Oregon Author: Craver, Daniel Robert Year: 2010 The decline of waterfowl populations and their requisite wetland habitats remains a concern. Because migratory bird refuges are often artificial landscapes of actively managed wetlands, and wildlife populations experience their greatest change during the breeding season, refuges should be designed to maximize breeding habitat. While past nest success studies have focused on at-nest variables, new approaches are needed to evaluate the effect of composition and configuration of plant communities at the landscape scale. This study aims to quantify landscape patterns within individual refuge management units to determine influence upon historical nesting success averages of ducks at Malheur National Wildlife Refuge in southeastern Oregon. The Mayfield estimate of nest success for 8 duck species yields a survival rate of 25% for the years 1987-1998 with a range of 0-74% across 48 management units. FRAGSTATS was used to calculate a suite of 9 landscape pattern metrics per unit at the class-level for each of 3 wetland habitat classes, and at the landscape-level using all habitat types. These 36 variables were tested for association with survival rate using Pearson R correlation. Results suggest fragmentation of dry meadow habitat; patch size, complexity, and extensiveness of wet meadow habitat; and diversity of habitats across the landscape positively influence duck nest success at the scale of the individual management unit. Title: Influence of Wetland Landscape Structure on Duck Nest Success at Malheur National Wildlife Refuge, Oregon Author: Craver, Daniel Robert Year: 2010 The decline of waterfowl populations and their requisite wetland habitats remains a concern. Because migratory bird refuges are often artificial landscapes of actively managed wetlands, and wildlife populations experience their greatest change during the breeding season, refuges should be designed to maximize breeding habitat. While past nest success studies have focused on at-nest variables, new approaches are needed to evaluate the effect of composition and configuration of plant communities at the landscape scale. This study aims to quantify landscape patterns within individual refuge management units to determine influence upon historical nesting success averages of ducks at Malheur National Wildlife Refuge in southeastern Oregon. The Mayfield estimate of nest success for 8 duck species yields a survival rate of 25% for the years 1987-1998 with a range of 0-74% across 48 management units. FRAGSTATS was used to calculate a suite of 9 landscape pattern metrics per unit at the class-level for each of 3 wetland habitat classes, and at the landscape-level using all habitat types. These 36 variables were tested for association with survival rate using Pearson R correlation. Results suggest fragmentation of dry meadow habitat; patch size, complexity, and extensiveness of wet meadow habitat; and diversity of habitats across the landscape positively influence duck nest success at the scale of the individual management unit. Close

• 7. [Article] Spruce Reach culvert project environmental assessment and finding of no significant impact

  26 pp. Map, references, illus. T21S., R11W., Sec 33. Date of FONSI is January 9, 2009. Captured January 14, 2009.

  Citation × Citation Citation Abstract Copy Title: Spruce Reach culvert project environmental assessment and finding of no significant impact Author: United States. Bureau of Land Management. Coos Bay District Year: 2009, 2008 26 pp. Map, references, illus. T21S., R11W., Sec 33. Date of FONSI is January 9, 2009. Captured January 14, 2009. Title: Spruce Reach culvert project environmental assessment and finding of no significant impact Author: United States. Bureau of Land Management. Coos Bay District Year: 2009, 2008 26 pp. Map, references, illus. T21S., R11W., Sec 33. Date of FONSI is January 9, 2009. Captured January 14, 2009. Close

• 8. [Article] Siletz Bay National Fish and Wildlife Refuge : environmental assessment

  "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively ...

  Citation × Citation Citation Abstract Copy Title: Siletz Bay National Fish and Wildlife Refuge : environmental assessment Author: U.S. Fish and Wildlife Service. Region 1, Harrison, Ben "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively managing 1,060 acres of tidelands with the State of Oregon... The primary need for the Service acquisition is to preserve diverse coastal wetland habitats and upland buffers for a variety of waterfowl, shorebirds, marine mammals, endangered species, raptors, songbirds, anadromous and resident fish, and other wildlife." (p.2) The report describes the area and discusses potential issues. It includes maps, an aerial photograph, and a species list. Title: Siletz Bay National Fish and Wildlife Refuge : environmental assessment Author: U.S. Fish and Wildlife Service. Region 1, Harrison, Ben "The Service is proposing to establish the Siletz Bay National Fish and Wildlife Refuge by initially accepting a donation of 46 acres of salt marsh, acquiring up to 793 acres of land, and cooperatively managing 1,060 acres of tidelands with the State of Oregon... The primary need for the Service acquisition is to preserve diverse coastal wetland habitats and upland buffers for a variety of waterfowl, shorebirds, marine mammals, endangered species, raptors, songbirds, anadromous and resident fish, and other wildlife." (p.2) The report describes the area and discusses potential issues. It includes maps, an aerial photograph, and a species list. Close

• 9. [Article] Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon

  Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated ...

  Citation × Citation Citation Abstract Copy Title: Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon Author: Adamus, Paul R. Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during winter, and with what intraseasonal regularity? (2) To what extent are these species associated - individually and collectively - with landscape and site-scale habitat variables? (3) To what extent are these species associated - individually and collectively - with particular landscape vs. site-scale variables? (4) How are the apparent associations affected by survey procedures and data analysis methods? Two survey procedures (area counts and point counts) in 1995 and 1996 found 104 species during 10 visits to 142 riparian and wetland sites. Area counts mainly surveyed waterbirds and raptors; point counts surveyed passerines. From area counts, mean richness ranged 0 toll species among sites and 1 to 5 species among weeks at an average site; mean number of individuals ranged 0 to 1016 among sites and from 6 to 199 among weeks at an average site. From point counts, richness ranged 1 to 6 species both among sites and among weeks at an average site. Mean number of individuals ranged 0 to 1016 per site and 6 to 199 among weeks at an average site. I individually examined 64 species to identify relative degree of association with site-scale and landscape variables. Winter Wren, Bewick's Wren, Hutton's Vireo, and Varied Thrush were significantly associated with woody cover at one or more spatial scales. Passerine abundance was greatest at sites with slowflowing water. Richness was associated with soil inundation category, peaking at intermediate frequencies and interacting with canopy cover and wooded patch extent. Richness of non-passerines was greater where standing water occupied >6% of the landscape nearest the site. Conclusions for many species and community metrics were sensitive to choice of survey methods, variables, measurement procedures, and statistical analysis tests. Ratings generated by OFWAM, a general tool for categorizing overall wetland habitat quality, did not significantly parallel measured richness and abundance of wintering birds. Title: Multiscale relationships of wintering birds with riparian and wetland habitat in the Willamette Valley, Oregon Author: Adamus, Paul R. Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during winter, and with what intraseasonal regularity? (2) To what extent are these species associated - individually and collectively - with landscape and site-scale habitat variables? (3) To what extent are these species associated - individually and collectively - with particular landscape vs. site-scale variables? (4) How are the apparent associations affected by survey procedures and data analysis methods? Two survey procedures (area counts and point counts) in 1995 and 1996 found 104 species during 10 visits to 142 riparian and wetland sites. Area counts mainly surveyed waterbirds and raptors; point counts surveyed passerines. From area counts, mean richness ranged 0 toll species among sites and 1 to 5 species among weeks at an average site; mean number of individuals ranged 0 to 1016 among sites and from 6 to 199 among weeks at an average site. From point counts, richness ranged 1 to 6 species both among sites and among weeks at an average site. Mean number of individuals ranged 0 to 1016 per site and 6 to 199 among weeks at an average site. I individually examined 64 species to identify relative degree of association with site-scale and landscape variables. Winter Wren, Bewick's Wren, Hutton's Vireo, and Varied Thrush were significantly associated with woody cover at one or more spatial scales. Passerine abundance was greatest at sites with slowflowing water. Richness was associated with soil inundation category, peaking at intermediate frequencies and interacting with canopy cover and wooded patch extent. Richness of non-passerines was greater where standing water occupied >6% of the landscape nearest the site. Conclusions for many species and community metrics were sensitive to choice of survey methods, variables, measurement procedures, and statistical analysis tests. Ratings generated by OFWAM, a general tool for categorizing overall wetland habitat quality, did not significantly parallel measured richness and abundance of wintering birds. Close

• 10. [Article] The Effects of Tide Gates on Estuarine Habitats and Migratory Fish

  Citation × Citation Citation Abstract Copy Title: The Effects of Tide Gates on Estuarine Habitats and Migratory Fish Author: Souder, Jon A., Giannico, Guillermo R. Title: The Effects of Tide Gates on Estuarine Habitats and Migratory Fish Author: Souder, Jon A., Giannico, Guillermo R. Close