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• 61. [Article] Structure-forming benthic invertebrates : habitat distributions on the continental margin of Oregon and Washington

  Structure-forming invertebrates belong to a polyphyletic group of primarily sessile and sedentary megafauna that can significantly enhance the complexity of physical habitats. A number of these organisms, ...

  Citation × Citation Citation Abstract Copy Title: Structure-forming benthic invertebrates : habitat distributions on the continental margin of Oregon and Washington Author: Strom, Natalie A. Structure-forming invertebrates belong to a polyphyletic group of primarily sessile and sedentary megafauna that can significantly enhance the complexity of physical habitats. A number of these organisms, including cold-water corals and sponges, are known to be slow growing and vulnerable to physical disturbance. In addition, as filter feeders, these invertebrates can indicate areas of consistently favorable conditions for feeding and growth. This study provides the first quantitative analysis of structure-forming invertebrate communities in many areas along the continental margin of Oregon and Washington. Geological surveys during 1992-95, using the occupied submersible, Delta, sampled an extensive area in this region, primarily on and around rock outcrops. The videos from these surveys were analyzed to inventory and catalog sessile structure-forming invertebrates and to document their associations with geological habitat types. Detailed data on geological substrate, invertebrate diversity, abundance, and density were compiled and analyzed. It was found that geological substrate and depth were reliable indicators of suitable habitat for most species included in the study. Gorgonian corals tended to concentrate in high densities in depths between 200-250m, at the southern edges of submerged rocky banks, and where hard rocky substrate was covered with a thick layer of sediment. Because of recent fishery regulation changes, this information can be used as baseline data for future studies on the effectiveness of closed areas on the recovery of structure-forming invertebrates from disturbance, particularly bottom trawling. Title: Structure-forming benthic invertebrates : habitat distributions on the continental margin of Oregon and Washington Author: Strom, Natalie A. Structure-forming invertebrates belong to a polyphyletic group of primarily sessile and sedentary megafauna that can significantly enhance the complexity of physical habitats. A number of these organisms, including cold-water corals and sponges, are known to be slow growing and vulnerable to physical disturbance. In addition, as filter feeders, these invertebrates can indicate areas of consistently favorable conditions for feeding and growth. This study provides the first quantitative analysis of structure-forming invertebrate communities in many areas along the continental margin of Oregon and Washington. Geological surveys during 1992-95, using the occupied submersible, Delta, sampled an extensive area in this region, primarily on and around rock outcrops. The videos from these surveys were analyzed to inventory and catalog sessile structure-forming invertebrates and to document their associations with geological habitat types. Detailed data on geological substrate, invertebrate diversity, abundance, and density were compiled and analyzed. It was found that geological substrate and depth were reliable indicators of suitable habitat for most species included in the study. Gorgonian corals tended to concentrate in high densities in depths between 200-250m, at the southern edges of submerged rocky banks, and where hard rocky substrate was covered with a thick layer of sediment. Because of recent fishery regulation changes, this information can be used as baseline data for future studies on the effectiveness of closed areas on the recovery of structure-forming invertebrates from disturbance, particularly bottom trawling. Close

• 62. [Article] Birds in a sagebrush sea: managing sagebrush habitats for bird communities

  Citation × Citation Citation Abstract Copy Title: Birds in a sagebrush sea: managing sagebrush habitats for bird communities Author: Ritter, Sharon A., Paige, Christine Title: Birds in a sagebrush sea: managing sagebrush habitats for bird communities Author: Ritter, Sharon A., Paige, Christine Close

• 63. [Article] A Place for nature : Willamette basin habitat conservation priorities

  An introduction to habitats in the Willamette River Basin.

  Citation × Citation Citation Abstract Copy Title: A Place for nature : Willamette basin habitat conservation priorities Author: Grossman, Elizabeth An introduction to habitats in the Willamette River Basin. Title: A Place for nature : Willamette basin habitat conservation priorities Author: Grossman, Elizabeth An introduction to habitats in the Willamette River Basin. Close

• 64. [Article] Female black bear habitat selection and home range ecology in the central Oregon Cascades

  Citation × Citation Citation Abstract Copy Title: Female black bear habitat selection and home range ecology in the central Oregon Cascades Author: Vander Heyden, Madeleine Title: Female black bear habitat selection and home range ecology in the central Oregon Cascades Author: Vander Heyden, Madeleine Close

• 65. [Article] Information Report 2018-01; Winter Habitat Condition of Oregon Coast Coho Salmon Populations, 2007-2014

  Abstract -- In this report we summarize results of eight years (2007-2014) of habitat surveys for 18 independent Oregon coast coho salmon populations across four monitoring strata (North Coast, Mid Coast, ...

  Citation × Citation Citation Abstract Copy Title: Information Report 2018-01; Winter Habitat Condition of Oregon Coast Coho Salmon Populations, 2007-2014 Abstract -- In this report we summarize results of eight years (2007-2014) of habitat surveys for 18 independent Oregon coast coho salmon populations across four monitoring strata (North Coast, Mid Coast, MidSouth Coast, and Umpqua) in the Oregon Coast Coho Salmon Evolutionary Significant Unit (ESU). We also sampled dependent population blocks across three monitoring strata (North Coast, Mid Coast, and Mid-South Coast). Using a spatially balanced site selection process (Generalized Random Tessellation Stratification; GRTS) we surveyed 451 unique sites within the range of coho salmon spawning or rearing. With the exception of the 2014 survey year, habitat data were collected during winter conditions (February – March). Habitat sampled in 2014 occurred within the summer field season (June – September). We used a Habitat Limiting Factors Model (HLFM) to estimate habitat capacity for winter coho parr and the HabRate model to assess habitat quality for each surveyed stream reach. HLFM estimates were expanded based on the total coho distribution in each population. Based on the habitat data the HLFM predicted the Floras population could support the highest density of juvenile coho (1568 parr/km), while the streams in the Siltcoos watershed could support the least (290 parr/km). At the ESU-level, there was no detectable change of high quality rearing habitat (= 1850 parr/km) when compared to previous studies, but changes were observed among populations over the course of these survey years. We compared individual habitat metrics across populations, land use, geology, and between independent and dependent populations. While no significant differences were observed between independent and dependent populations, differences in habitat metrics were detected among individual populations, land use types, and geologies. In addition, we detected a difference in reproductive habitat quality (spawning and emergence) between both populations and land use types. Title: Information Report 2018-01; Winter Habitat Condition of Oregon Coast Coho Salmon Populations, 2007-2014 Abstract -- In this report we summarize results of eight years (2007-2014) of habitat surveys for 18 independent Oregon coast coho salmon populations across four monitoring strata (North Coast, Mid Coast, MidSouth Coast, and Umpqua) in the Oregon Coast Coho Salmon Evolutionary Significant Unit (ESU). We also sampled dependent population blocks across three monitoring strata (North Coast, Mid Coast, and Mid-South Coast). Using a spatially balanced site selection process (Generalized Random Tessellation Stratification; GRTS) we surveyed 451 unique sites within the range of coho salmon spawning or rearing. With the exception of the 2014 survey year, habitat data were collected during winter conditions (February – March). Habitat sampled in 2014 occurred within the summer field season (June – September). We used a Habitat Limiting Factors Model (HLFM) to estimate habitat capacity for winter coho parr and the HabRate model to assess habitat quality for each surveyed stream reach. HLFM estimates were expanded based on the total coho distribution in each population. Based on the habitat data the HLFM predicted the Floras population could support the highest density of juvenile coho (1568 parr/km), while the streams in the Siltcoos watershed could support the least (290 parr/km). At the ESU-level, there was no detectable change of high quality rearing habitat (= 1850 parr/km) when compared to previous studies, but changes were observed among populations over the course of these survey years. We compared individual habitat metrics across populations, land use, geology, and between independent and dependent populations. While no significant differences were observed between independent and dependent populations, differences in habitat metrics were detected among individual populations, land use types, and geologies. In addition, we detected a difference in reproductive habitat quality (spawning and emergence) between both populations and land use types. Close

• 66. [Article] Limiting Factors Assessment and Restoration Plan: Olalla Creek Tributary of the Yaquina Estuary

  Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Olalla Creek subbasin in Lincoln County, Oregon. The report contains information ...

  Citation × Citation Citation Abstract Copy Title: Limiting Factors Assessment and Restoration Plan: Olalla Creek Tributary of the Yaquina Estuary Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Olalla Creek subbasin in Lincoln County, Oregon. The report contains information on the physical setting, current status of Coho, resources used in developing the plan, general questions that guided the assessment, pre-survey mapping/location of habitat subdivisions, secondary branch habitats, critical contributing areas, lowland area, summer and winter habitat assessment, lake habitat, location of other resources, juvenile Coho, evaluation of habitat quality and Coho production, Field Assessment, location of potential migration barriers, potential sites for restoration work, morphology, rank of restoration efforts, riparian corridor, and core area. Title: Limiting Factors Assessment and Restoration Plan: Olalla Creek Tributary of the Yaquina Estuary Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Olalla Creek subbasin in Lincoln County, Oregon. The report contains information on the physical setting, current status of Coho, resources used in developing the plan, general questions that guided the assessment, pre-survey mapping/location of habitat subdivisions, secondary branch habitats, critical contributing areas, lowland area, summer and winter habitat assessment, lake habitat, location of other resources, juvenile Coho, evaluation of habitat quality and Coho production, Field Assessment, location of potential migration barriers, potential sites for restoration work, morphology, rank of restoration efforts, riparian corridor, and core area. Close

• 67. [Article] Limiting Factors Assessment and Restoration Plan: Rock Creek Tributary to Devil's Lake Lincoln County

  Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Rock Creek / Devils Lake basin in Lincoln County, Oregon. The report contains ...

  Citation × Citation Citation Abstract Copy Title: Limiting Factors Assessment and Restoration Plan: Rock Creek Tributary to Devil's Lake Lincoln County Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Rock Creek / Devils Lake basin in Lincoln County, Oregon. The report contains information on the physical setting, current status of Coho, resources used in developing the plan, general questions that guided the assessment, pre-survey mapping/location of habitat subdivisons, secondary branch habitats, critical contributing areas, lowland area, summer and winter habitat assessment, lake habitat, location of other resources, juvenile Coho, evaluation of habitat quality and Coho production, Field Assessment, location of potential migration barriers, potential sites for restoration work, morphology, rank of restoration efforts, riparian corridor, and core area. Title: Limiting Factors Assessment and Restoration Plan: Rock Creek Tributary to Devil's Lake Lincoln County Abstract -- This document provides watershed restoration actions proposed to enhance the Coho Salmon population within the Rock Creek / Devils Lake basin in Lincoln County, Oregon. The report contains information on the physical setting, current status of Coho, resources used in developing the plan, general questions that guided the assessment, pre-survey mapping/location of habitat subdivisons, secondary branch habitats, critical contributing areas, lowland area, summer and winter habitat assessment, lake habitat, location of other resources, juvenile Coho, evaluation of habitat quality and Coho production, Field Assessment, location of potential migration barriers, potential sites for restoration work, morphology, rank of restoration efforts, riparian corridor, and core area. Close

• 68. [Article] Upper Nehelam Habitat Assessments - Winter 2006 & 2007

  Abstract -- Project staff utilized the ODFW Aquatic Inventory protocol to assess habitat in selected small, medium, and large sized streams in the Upper Nehalem basin. In addition, the project personnel ...

  Citation × Citation Citation Abstract Copy Title: Upper Nehelam Habitat Assessments - Winter 2006 & 2007 Abstract -- Project staff utilized the ODFW Aquatic Inventory protocol to assess habitat in selected small, medium, and large sized streams in the Upper Nehalem basin. In addition, the project personnel conducted a snorkeling survey to estimate juvenile salmonid distribution in these streams. The 2006 and 2007 habitat surveys completed the remaining non-surveyed Coho freshwater habitat streams found within the Upper Nehalem. During the 2006 and 2007 seasons we surveyed 218 stream reaches in 87 streams totaling 242.82 kilometers (150.54 miles) of habitat. In addition, the project staff snorkeled 445 pools within the surveyed areas. Title: Upper Nehelam Habitat Assessments - Winter 2006 & 2007 Abstract -- Project staff utilized the ODFW Aquatic Inventory protocol to assess habitat in selected small, medium, and large sized streams in the Upper Nehalem basin. In addition, the project personnel conducted a snorkeling survey to estimate juvenile salmonid distribution in these streams. The 2006 and 2007 habitat surveys completed the remaining non-surveyed Coho freshwater habitat streams found within the Upper Nehalem. During the 2006 and 2007 seasons we surveyed 218 stream reaches in 87 streams totaling 242.82 kilometers (150.54 miles) of habitat. In addition, the project staff snorkeled 445 pools within the surveyed areas. Close

• 69. [Article] Defining micro-habitat relationships for juvenile black rockfish, Sebastes melanops

  The functioning of marine habitats needs to be understood in the context of the ecological relationships and associations between organisms and the physical and biogenic environment they inhabit. Thus, ...

  Citation × Citation Citation Abstract Copy Title: Defining micro-habitat relationships for juvenile black rockfish, Sebastes melanops Author: Mann, Marion E. The functioning of marine habitats needs to be understood in the context of the ecological relationships and associations between organisms and the physical and biogenic environment they inhabit. Thus, it becomes important to explore and define habitat features which contribute to these relationships and which are important in the life history of a species. Juvenile habitat needs and associations have rarely been studied, but Essential Fish Habitat (EFH) guidelines require description of habitat for all life stages of managed stocks. Given observational data in the natural environment, there is a strong need to determine if structural or biogenic habitat matters to fish. To explore direct relationships with habitat features, based on cause and effect, requires controlled laboratory studies. In this work, the extent and nature of habitat relationships for juvenile black rockfish, Sebastes melanops, were systematically investigated in four consecutive controlled experiments. I examined habitat choices of juvenile rockfish with respect to (1) a diurnal light cycle, (2) the nature of structure use with respect to the importance of crevices, (3) the effect of additional complexity in structure, and (4) the role of biotic components of structure independent of their physical attributes. In the first experiment (1), juvenile rockfish behavior was video taped during day, crepuscular and night conditions. To observe fish behavior at night an infrared tank set-up was used, with lights projecting through the bottom of the tanks. The sand layer was required to be very thin, such that the light could penetrate through both tank wall and sand and get picked up by an overhead camera. This exposed many crevices and ledges at the base of the boulders which were extensively used by all groups of fish. In the second experiment (2), burying the boulders in deep sand reduced this crevice availability and took away those types of refuge opportunities. Complexity was then examined by attaching white plumed anemones, Metridium spp. to half of the boulders in the tanks (experiment 3). White plumed anemones occur as two species on the west coast of North America, Metridium farcimen and M. senile fimbriatum, which are visually indistinguishable and have overlapping distributions. For the purposes of our experiments, it was not necessary to identify them to species level, and all the experimental animals were collected by scuba in Yaquina Bay. Artificial replicates of Metridium spp. in comparison with live animals were used to test for biogenic contributions to habitat preference (experiment 4). To see if associations and behaviors observed in the laboratory also occur in the field, habitat use by unidentified reef-associated juvenile rockfish in their natural environment was examined using video data collected by the Oregon Department of Fish and Wildlife with a remotely operated vehicle. The results of the experiments indicate that (1) the odds of juvenile black rockfish being present in boulders during daylight were 7.2 times greater than at nighttime. It is likely that refuge needs for juveniles of this species are greatest during daylight given the diversity of visual predators. (2) Crevice availability plays an important role in providing refuge, but juvenile black rockfish in my trials did not change boulder use based on crevice availability. (3) Juvenile black rockfish also clearly preferred habitat complexity (added anemones) and preferred boulders with attached Metridium spp. over plain boulders. (4) Preference was given not only to higher structural complexity, but also to habitat that offered a biotic component to the boulder/anemone arrangement. Juvenile black rockfish showed a significant association with boulder habitat containing attached live Metridium spp. over boulder habitat with the same structural construct using plastic replicas. The specific nature of this biogenic contribution to habitat choice is unknown and could be the result of an important symbiotic relationship. In their natural environment, unidentified juvenile rockfish also occurred in greater numbers in micro-habitats highly populated by Metridium spp. This work demonstrates that reef associated juvenile black rockfish engage in complex micro-habitat relationships that are not only based on structural complexity but also on biogenic influences. Biogenic habitats frequently involve invertebrate species that are fragile and long lived, and thus vulnerable to disturbance (e.g. from global warming, fishing activities and other extraction processes). Although survival and growth of juvenile black rockfish was not investigated in this work, the loss of biogenic habitat is likely to impact post settlement survival of reef-associated fishes, thus ultimately affecting population recruitment. Habitat limitations in the juvenile stage are particularly important to understand because density-dependent factors can dampen high stochasticity in recruitment to adult populations. Title: Defining micro-habitat relationships for juvenile black rockfish, Sebastes melanops Author: Mann, Marion E. The functioning of marine habitats needs to be understood in the context of the ecological relationships and associations between organisms and the physical and biogenic environment they inhabit. Thus, it becomes important to explore and define habitat features which contribute to these relationships and which are important in the life history of a species. Juvenile habitat needs and associations have rarely been studied, but Essential Fish Habitat (EFH) guidelines require description of habitat for all life stages of managed stocks. Given observational data in the natural environment, there is a strong need to determine if structural or biogenic habitat matters to fish. To explore direct relationships with habitat features, based on cause and effect, requires controlled laboratory studies. In this work, the extent and nature of habitat relationships for juvenile black rockfish, Sebastes melanops, were systematically investigated in four consecutive controlled experiments. I examined habitat choices of juvenile rockfish with respect to (1) a diurnal light cycle, (2) the nature of structure use with respect to the importance of crevices, (3) the effect of additional complexity in structure, and (4) the role of biotic components of structure independent of their physical attributes. In the first experiment (1), juvenile rockfish behavior was video taped during day, crepuscular and night conditions. To observe fish behavior at night an infrared tank set-up was used, with lights projecting through the bottom of the tanks. The sand layer was required to be very thin, such that the light could penetrate through both tank wall and sand and get picked up by an overhead camera. This exposed many crevices and ledges at the base of the boulders which were extensively used by all groups of fish. In the second experiment (2), burying the boulders in deep sand reduced this crevice availability and took away those types of refuge opportunities. Complexity was then examined by attaching white plumed anemones, Metridium spp. to half of the boulders in the tanks (experiment 3). White plumed anemones occur as two species on the west coast of North America, Metridium farcimen and M. senile fimbriatum, which are visually indistinguishable and have overlapping distributions. For the purposes of our experiments, it was not necessary to identify them to species level, and all the experimental animals were collected by scuba in Yaquina Bay. Artificial replicates of Metridium spp. in comparison with live animals were used to test for biogenic contributions to habitat preference (experiment 4). To see if associations and behaviors observed in the laboratory also occur in the field, habitat use by unidentified reef-associated juvenile rockfish in their natural environment was examined using video data collected by the Oregon Department of Fish and Wildlife with a remotely operated vehicle. The results of the experiments indicate that (1) the odds of juvenile black rockfish being present in boulders during daylight were 7.2 times greater than at nighttime. It is likely that refuge needs for juveniles of this species are greatest during daylight given the diversity of visual predators. (2) Crevice availability plays an important role in providing refuge, but juvenile black rockfish in my trials did not change boulder use based on crevice availability. (3) Juvenile black rockfish also clearly preferred habitat complexity (added anemones) and preferred boulders with attached Metridium spp. over plain boulders. (4) Preference was given not only to higher structural complexity, but also to habitat that offered a biotic component to the boulder/anemone arrangement. Juvenile black rockfish showed a significant association with boulder habitat containing attached live Metridium spp. over boulder habitat with the same structural construct using plastic replicas. The specific nature of this biogenic contribution to habitat choice is unknown and could be the result of an important symbiotic relationship. In their natural environment, unidentified juvenile rockfish also occurred in greater numbers in micro-habitats highly populated by Metridium spp. This work demonstrates that reef associated juvenile black rockfish engage in complex micro-habitat relationships that are not only based on structural complexity but also on biogenic influences. Biogenic habitats frequently involve invertebrate species that are fragile and long lived, and thus vulnerable to disturbance (e.g. from global warming, fishing activities and other extraction processes). Although survival and growth of juvenile black rockfish was not investigated in this work, the loss of biogenic habitat is likely to impact post settlement survival of reef-associated fishes, thus ultimately affecting population recruitment. Habitat limitations in the juvenile stage are particularly important to understand because density-dependent factors can dampen high stochasticity in recruitment to adult populations. Close

• 70. [Article] Sagebrush / Sage Grouse Habitat Metric: User's guide

  The metric is encompassed in two documents, the Sagebrush/Sage Grouse Habitat Metric User’s Guide and a Sagebrush/Sage Grouse Habitat Metric Calculator .

  Citation × Citation Citation Abstract Copy Title: Sagebrush / Sage Grouse Habitat Metric: User's guide Author: Defenders of Wildlife The metric is encompassed in two documents, the Sagebrush/Sage Grouse Habitat Metric User’s Guide and a Sagebrush/Sage Grouse Habitat Metric Calculator . Title: Sagebrush / Sage Grouse Habitat Metric: User's guide Author: Defenders of Wildlife The metric is encompassed in two documents, the Sagebrush/Sage Grouse Habitat Metric User’s Guide and a Sagebrush/Sage Grouse Habitat Metric Calculator . Close