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• 1. [Article] Wildlife habitats in managed rangelands : the Great Basin of southeastern Oregon

  Citation × Citation Citation Abstract Copy Title: Wildlife habitats in managed rangelands : the Great Basin of southeastern Oregon Author: Hall, Frederick C. Title: Wildlife habitats in managed rangelands : the Great Basin of southeastern Oregon Author: Hall, Frederick C. Close

• 2. [Article] Habitat selection by nesting Swainson's hawks : a hierarchical approach

  The habitat relationships of Swainson's hawks in northern California were studied at several levels of resolution: 1) distribution of hawk populations among three adjacent geographic areas, 2) density ...

  Citation × Citation Citation Abstract Copy Title: Habitat selection by nesting Swainson's hawks : a hierarchical approach Author: Woodbridge, Brian The habitat relationships of Swainson's hawks in northern California were studied at several levels of resolution: 1) distribution of hawk populations among three adjacent geographic areas, 2) density of hawk territories among landscapes within a single geographic area, 3) habitats associated with individual nesting territories, and 4) selection of foraging habitats and prey resources by individual hawks. Patterns of habitat selection observed at each level were compared to results obtained at other levels, and to temporal variations in habitat quality. Individual Swainson's hawks exhibited strong selection for specific habitats wherein prey availability was highest, however these habitats were not found in increased proportions in Swainson's hawk territories. Similarly, densities of Swainson's hawk territories among different landscapes did not reflect the availability of high-quality habitat; many pairs nested in marginal habitats and exhibited low reproductive success and large areas of apparently suitable habitat were unoccupied. At a larger scale, the distribution of Swainson's hawk populations was markedly dissimilar among three adjacent geographic areas with similar habitat composition. Lack of concordance among levels of habitat selection by Swainson's hawks was explained by behavioral and environmental factors that constrain optimal habitat selection. I suggest that high temporal variability of habitats in agricultural environments, combined with site tenacity and natal site philopatry by nesting hawks, prevented the density and distribution of the hawk population from closely tracking the available habitat. Reproductive fitness, however, was strongly associated with habitat quality. Title: Habitat selection by nesting Swainson's hawks : a hierarchical approach Author: Woodbridge, Brian The habitat relationships of Swainson's hawks in northern California were studied at several levels of resolution: 1) distribution of hawk populations among three adjacent geographic areas, 2) density of hawk territories among landscapes within a single geographic area, 3) habitats associated with individual nesting territories, and 4) selection of foraging habitats and prey resources by individual hawks. Patterns of habitat selection observed at each level were compared to results obtained at other levels, and to temporal variations in habitat quality. Individual Swainson's hawks exhibited strong selection for specific habitats wherein prey availability was highest, however these habitats were not found in increased proportions in Swainson's hawk territories. Similarly, densities of Swainson's hawk territories among different landscapes did not reflect the availability of high-quality habitat; many pairs nested in marginal habitats and exhibited low reproductive success and large areas of apparently suitable habitat were unoccupied. At a larger scale, the distribution of Swainson's hawk populations was markedly dissimilar among three adjacent geographic areas with similar habitat composition. Lack of concordance among levels of habitat selection by Swainson's hawks was explained by behavioral and environmental factors that constrain optimal habitat selection. I suggest that high temporal variability of habitats in agricultural environments, combined with site tenacity and natal site philopatry by nesting hawks, prevented the density and distribution of the hawk population from closely tracking the available habitat. Reproductive fitness, however, was strongly associated with habitat quality. Close

• 3. [Article] Floodplain Habitat Metric: User’s Guide

  The metric is encompassed in two documents, this Floodplain Habitat Metric User’s Guide and a Floodplain Habitat Calculator.

  Citation × Citation Citation Abstract Copy Title: Floodplain Habitat Metric: User’s Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Floodplain Habitat Metric User’s Guide and a Floodplain Habitat Calculator. Title: Floodplain Habitat Metric: User’s Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Floodplain Habitat Metric User’s Guide and a Floodplain Habitat Calculator. Close

• 4. [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

• 5. [Article] Floodplain user guide.pdf

  Citation × Citation Citation Abstract Copy Title: Floodplain user guide.pdf Author: Defenders of Wildlife Title: Floodplain user guide.pdf Author: Defenders of Wildlife Close

• 6. [Article] Floodplain_Habitat_Metric_Calculator.Version_1.0.protected.xlsx

  Citation × Citation Citation Abstract Copy Title: Floodplain_Habitat_Metric_Calculator.Version_1.0.protected.xlsx Author: Defenders of Wildlife Title: Floodplain_Habitat_Metric_Calculator.Version_1.0.protected.xlsx Author: Defenders of Wildlife Close

• 7. [Article] Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem

  The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat ...

  Citation × Citation Citation Abstract Copy Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Close

• 8. [Article] Habitat quality and assessing risks to avian biodiversity

  Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. ...

  Citation × Citation Citation Abstract Copy Title: Habitat quality and assessing risks to avian biodiversity Author: Barczak, Mary J. Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. This study introduces the use of habitat quality in a biodiversity risk model to determine the significance of habitat quality when predicting risks to biodiversity due to landscape change. The difference between residential and forest habitats in terms of habitat quality for breeding birds was used to test the significance of habitat quality to the risk model. Relative habitat quality was estimated from population densities for 62 bird species associated with both forest and residential habitats. The effect of habitat quality was tested using two possible future landscapes: Buildout and Spine. Predicted risk for the 62 bird species due to landscape change increased by 74% in the Buildout Landscape and 31% in the Spine Landscape when habitat quality was considered. The life history traits of species most at risk were compared to the traits of species that benefited from the landscape change. Life history traits considered included foraging strategy, nest type and placement, migratory status, and area sensitivity. Species at high risk included ground nesters, foliage and tree trunk gleaners, neotropical migrants, and area sensitive species. Title: Habitat quality and assessing risks to avian biodiversity Author: Barczak, Mary J. Models that assess the risk to biodiversity from landscape change can help communities prioritize planning decisions. Accurate representation of the ecology and life history traits of species is necessary. This study introduces the use of habitat quality in a biodiversity risk model to determine the significance of habitat quality when predicting risks to biodiversity due to landscape change. The difference between residential and forest habitats in terms of habitat quality for breeding birds was used to test the significance of habitat quality to the risk model. Relative habitat quality was estimated from population densities for 62 bird species associated with both forest and residential habitats. The effect of habitat quality was tested using two possible future landscapes: Buildout and Spine. Predicted risk for the 62 bird species due to landscape change increased by 74% in the Buildout Landscape and 31% in the Spine Landscape when habitat quality was considered. The life history traits of species most at risk were compared to the traits of species that benefited from the landscape change. Life history traits considered included foraging strategy, nest type and placement, migratory status, and area sensitivity. Species at high risk included ground nesters, foliage and tree trunk gleaners, neotropical migrants, and area sensitive species. Close

• 9. [Article] Oak Habitat Metric: User's Guide

  The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator.

  Citation × Citation Citation Abstract Copy Title: Oak Habitat Metric: User's Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator. Title: Oak Habitat Metric: User's Guide Author: Defenders of Wildlife The metric is encompassed in two documents, this Oak Habitat Metric User’s Guide and an Oak Habitat Calculator. Close

• 10. [Article] Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef

  This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and ...

  Citation × Citation Citation Abstract Copy Title: Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef Author: Merems, Arlene, Appy, Marcus, Romsos, Chris, Weeks, Hal, Fox, David, Amend, Mark This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and a nearly unfished reef off Cape Perpetua. There are over 17,000 angler trips for groundfish out of Depoe Bay annually, many choosing to fish Siletz Reef. In addition, numerous whale watching and sightseeing charter vessels operate in the vicinity of the reef. Cape Perpetua Reef consists of isolated patches of rock, and is too far from Newport (the nearest port) to receive much fishing effort. This examination of the influences of fishing pressure in nearshore rocky habitat complements, and is embedded in, a broader effort to understand the distribution and character of Oregon’s nearshore rocky reefs, and the species that are dependent upon them for habitat. The ODFW Marine Habitat Project has spent the last eight years working in cooperation with scientists and other resource agencies to develop methods for classifying and mapping nearshore rocky reefs habitats off Oregon. Because nearshore reefs are in state waters, Oregon is responsible for managing these living resources and habitats to sustain their long-term use and productivity. To date, eight reefs have been surveyed and mapped with sidescan and/or multibeam bathymetry at a resolution indicative of fish habitat. ODFW has also been developing non-extractive fish survey techniques to describe fish-habitat associations and estimate fish abundance at the habitat and reef scale. The importance of habitat to reef species cannot be over-stated and is now widely accepted in the scientific community and is the focus of major research efforts in other Pacific coastal states. Better understanding of the degree to which harvest influences relative and absolute abundance, combined with species-habitat relationships, is essential for resource managers to exercise their stewardship responsibilities to protect 5 essential habitat, develop population indices for species at risk, and maintain healthy and productive ecological systems. Title: Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef Author: Merems, Arlene, Appy, Marcus, Romsos, Chris, Weeks, Hal, Fox, David, Amend, Mark This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and a nearly unfished reef off Cape Perpetua. There are over 17,000 angler trips for groundfish out of Depoe Bay annually, many choosing to fish Siletz Reef. In addition, numerous whale watching and sightseeing charter vessels operate in the vicinity of the reef. Cape Perpetua Reef consists of isolated patches of rock, and is too far from Newport (the nearest port) to receive much fishing effort. This examination of the influences of fishing pressure in nearshore rocky habitat complements, and is embedded in, a broader effort to understand the distribution and character of Oregon’s nearshore rocky reefs, and the species that are dependent upon them for habitat. The ODFW Marine Habitat Project has spent the last eight years working in cooperation with scientists and other resource agencies to develop methods for classifying and mapping nearshore rocky reefs habitats off Oregon. Because nearshore reefs are in state waters, Oregon is responsible for managing these living resources and habitats to sustain their long-term use and productivity. To date, eight reefs have been surveyed and mapped with sidescan and/or multibeam bathymetry at a resolution indicative of fish habitat. ODFW has also been developing non-extractive fish survey techniques to describe fish-habitat associations and estimate fish abundance at the habitat and reef scale. The importance of habitat to reef species cannot be over-stated and is now widely accepted in the scientific community and is the focus of major research efforts in other Pacific coastal states. Better understanding of the degree to which harvest influences relative and absolute abundance, combined with species-habitat relationships, is essential for resource managers to exercise their stewardship responsibilities to protect 5 essential habitat, develop population indices for species at risk, and maintain healthy and productive ecological systems. Close