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• 1. [Article] Effects of wildfire on growth and demographics of coastal cutthroat trout in headwater streams

  Wildfire is a largely terrestrial perturbation broadly recognized as an agent of disturbance and ecological change in forested biomes. Effects of post-fire conditions on biotic components of aquatic systems ...

  Citation × Citation Citation Abstract Copy Title: Effects of wildfire on growth and demographics of coastal cutthroat trout in headwater streams Author: Heck, Michael P. Wildfire is a largely terrestrial perturbation broadly recognized as an agent of disturbance and ecological change in forested biomes. Effects of post-fire conditions on biotic components of aquatic systems have been less well-documented, although hypothetically, the two are strongly connected. In fact, the influence of wildfire may be most profound in headwater streams because of the tight linkage between aquatic and terrestrial ecosystems. We sought to understand the influence of post-fire conditions on fish in headwater streams by observing growth and demographics of coastal cutthroat trout (Oncorhynchus clarkii clarkii) following wildfire. During the summer of 2002, wildfire burned portions of three headwater watersheds in the North Umpqua basin of western Oregon. Burn severities ranged from moderate to severe. A reference stream was selected from a nearby fourth watershed. All fish-bearing portions of the stream network in the four watersheds were surveyed for 3 years following the wildfire, and 1,295 scale samples were collected from coastal cutthroat trout for age and growth analysis. Stream temperatures in the burned watersheds changed significantly following the wildfire (p < 0.016), with increases of up to 23% in the most severely burned watershed. During summer electrofishing surveys in the burned watersheds, both young-of-the-year and fish ≥ age 1 were captured; in the unburned watershed, the vast majority of fish captured were ≥ age 1. Age-frequency analyses revealed that fish in older age classes (age ≥ 3) were more prevalent in the unburned watershed than in the burned watersheds. Relative growth rates and length at last annulus formation of coastal cutthroat trout were positively related to the number of degree days during the growing season, and Pearson correlation coefficients ranged from 0.60 (p < 0.07) to 0.90 (p < 0.01). Growth rates and size of fish were not significantly correlated with relative density of fish (p ≥ 0.14). Contrary to the commonly held assumption that wildfire is detrimental to biota in aquatic systems, these results suggest that in the short term (≤ 3 years), fish in the study streams adjusted to environmental change caused by wildfire. Title: Effects of wildfire on growth and demographics of coastal cutthroat trout in headwater streams Author: Heck, Michael P. Wildfire is a largely terrestrial perturbation broadly recognized as an agent of disturbance and ecological change in forested biomes. Effects of post-fire conditions on biotic components of aquatic systems have been less well-documented, although hypothetically, the two are strongly connected. In fact, the influence of wildfire may be most profound in headwater streams because of the tight linkage between aquatic and terrestrial ecosystems. We sought to understand the influence of post-fire conditions on fish in headwater streams by observing growth and demographics of coastal cutthroat trout (Oncorhynchus clarkii clarkii) following wildfire. During the summer of 2002, wildfire burned portions of three headwater watersheds in the North Umpqua basin of western Oregon. Burn severities ranged from moderate to severe. A reference stream was selected from a nearby fourth watershed. All fish-bearing portions of the stream network in the four watersheds were surveyed for 3 years following the wildfire, and 1,295 scale samples were collected from coastal cutthroat trout for age and growth analysis. Stream temperatures in the burned watersheds changed significantly following the wildfire (p < 0.016), with increases of up to 23% in the most severely burned watershed. During summer electrofishing surveys in the burned watersheds, both young-of-the-year and fish ≥ age 1 were captured; in the unburned watershed, the vast majority of fish captured were ≥ age 1. Age-frequency analyses revealed that fish in older age classes (age ≥ 3) were more prevalent in the unburned watershed than in the burned watersheds. Relative growth rates and length at last annulus formation of coastal cutthroat trout were positively related to the number of degree days during the growing season, and Pearson correlation coefficients ranged from 0.60 (p < 0.07) to 0.90 (p < 0.01). Growth rates and size of fish were not significantly correlated with relative density of fish (p ≥ 0.14). Contrary to the commonly held assumption that wildfire is detrimental to biota in aquatic systems, these results suggest that in the short term (≤ 3 years), fish in the study streams adjusted to environmental change caused by wildfire. Close

• 2. [Article] Accuracy and suitability of several stand sampling methods in riparian zones

  Stand structure in headwater riparian areas of western Oregon is highly variable making quantification of structural attributes within these stands difficult. A reliable sampling design is important to ...

  Citation × Citation Citation Abstract Copy Title: Accuracy and suitability of several stand sampling methods in riparian zones Author: Marquardt, Theresa Stand structure in headwater riparian areas of western Oregon is highly variable making quantification of structural attributes within these stands difficult. A reliable sampling design is important to characterize and monitor changes in stand structure over time. This study examined sixteen alternatives for sampling live conifers and six alternatives for sampling hardwoods and snags. Each sampling alternative was replicated 500 times on a 72 meter square stem map at eight headwater stream locations in western Oregon. A variety of plot sizes and shapes were considered at two sampling intensities of 10 % and 20 % of the stand area. Applied to live conifers, the performance of the alternatives were assessed with respect to estimation of trees per hectare, basal area per hectare, and height to diameter ratio using root mean square error, average mean deviation and percent bias as criteria. Performance with respect to snags and hardwoods was similar. In general, rectangular strip designs oriented perpendicular to the stream outperformed circular, radial plots, and variable plots. Title: Accuracy and suitability of several stand sampling methods in riparian zones Author: Marquardt, Theresa Stand structure in headwater riparian areas of western Oregon is highly variable making quantification of structural attributes within these stands difficult. A reliable sampling design is important to characterize and monitor changes in stand structure over time. This study examined sixteen alternatives for sampling live conifers and six alternatives for sampling hardwoods and snags. Each sampling alternative was replicated 500 times on a 72 meter square stem map at eight headwater stream locations in western Oregon. A variety of plot sizes and shapes were considered at two sampling intensities of 10 % and 20 % of the stand area. Applied to live conifers, the performance of the alternatives were assessed with respect to estimation of trees per hectare, basal area per hectare, and height to diameter ratio using root mean square error, average mean deviation and percent bias as criteria. Performance with respect to snags and hardwoods was similar. In general, rectangular strip designs oriented perpendicular to the stream outperformed circular, radial plots, and variable plots. Close

• 3. [Article] Short-term response of Dicamptodon tenebrosus larvae to timber management in southwestern Oregon

  This is the publisher’s final pdf. The article is copyrighted by The Wildlife Society and published by John Wiley & Sons, Inc. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291937-2817. ...

  Citation × Citation Citation Abstract Copy Title: Short-term response of Dicamptodon tenebrosus larvae to timber management in southwestern Oregon Author: Adams, Michael J., Hayes, John P., Leuthold, Niels This is the publisher’s final pdf. The article is copyrighted by The Wildlife Society and published by John Wiley & Sons, Inc. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291937-2817. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Short-term response of Dicamptodon tenebrosus larvae to timber management in southwestern Oregon Author: Adams, Michael J., Hayes, John P., Leuthold, Niels This is the publisher’s final pdf. The article is copyrighted by The Wildlife Society and published by John Wiley & Sons, Inc. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291937-2817. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 4. [Article] Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors ...

  Citation × Citation Citation Abstract Copy Title: Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead Author: Schreck, Carl B., Olson, Douglas E., Schaller, Howard A., Brignon, William R. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Factors influencing density, distribution, and mesohabitat selection of juvenile wild salmonids and residual hatchery winter steelhead Author: Schreck, Carl B., Olson, Douglas E., Schaller, Howard A., Brignon, William R. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 5. [Article] Twenty-year changes in riparian bird communities of east-central Oregon

  Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing ...

  Citation × Citation Citation Abstract Copy Title: Twenty-year changes in riparian bird communities of east-central Oregon Author: Ellis, Michael S. Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing interest in exploring avian-habitat relationships in these systems to better inform land management, few studies have attempted to describe temporal changes in the region's riparian bird communities. To provide a frame of reference for these changes, we compared indices of avian abundance and diversity from three streamside vegetation associations in east-central Oregon during the 2014 breeding season with baseline data collected by TA Sanders and WD Edge in 1993 and 1994 (Sanders and Edge 1998). Our objectives were to identify patterns of change in the avian community with a focus on riparian shrub-dependent species, to re-examine previously reported relationships between avian abundance and vegetation volume, and to identify possible causes of declines in abundance and diversity with the goal of providing land managers in the semi-arid region information to be used in the guidance and adaptation of management practices. We combined field protocols used by Sanders and Edge to survey birds along point count transects and to measure riparian vegetation with modern analytical techniques. We found few major differences in overall diversity between study periods, but documented precipitous declines in detections for two of three riparian shrub-dependent focal species - Yellow Warbler (Setophaga petechia) and Willow Flycatcher (Empidonax trailii). Song Sparrow (Melospiza melodia) detections declined by a smaller margin. Changes in number of detections for these species did not reflect trends in mesic shrub volume, which had been identified as a likely driver of obligate species abundance by Sanders and Edge but remained relatively unchanged between study periods. Declines of all three focal species reflected regional Breeding Bird Survey trends, corroborating our finding that their declines may not be a result of changes in local site conditions. Compositional similarity between avian communities was significantly higher in 2014 than in 1993-1994, exhibiting a shift toward greater homogenization between structurally distinct riparian habitats. Our results suggest managing working lands for riparian shrub cover or volume, an important metric of grazing intensity and riparian system health, may not be enough to conserve diversity and abundance of riparian-shrub dependent birds, and more work should be done to identify and alleviate factors contributing to these species' declines. Title: Twenty-year changes in riparian bird communities of east-central Oregon Author: Ellis, Michael S. Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing interest in exploring avian-habitat relationships in these systems to better inform land management, few studies have attempted to describe temporal changes in the region's riparian bird communities. To provide a frame of reference for these changes, we compared indices of avian abundance and diversity from three streamside vegetation associations in east-central Oregon during the 2014 breeding season with baseline data collected by TA Sanders and WD Edge in 1993 and 1994 (Sanders and Edge 1998). Our objectives were to identify patterns of change in the avian community with a focus on riparian shrub-dependent species, to re-examine previously reported relationships between avian abundance and vegetation volume, and to identify possible causes of declines in abundance and diversity with the goal of providing land managers in the semi-arid region information to be used in the guidance and adaptation of management practices. We combined field protocols used by Sanders and Edge to survey birds along point count transects and to measure riparian vegetation with modern analytical techniques. We found few major differences in overall diversity between study periods, but documented precipitous declines in detections for two of three riparian shrub-dependent focal species - Yellow Warbler (Setophaga petechia) and Willow Flycatcher (Empidonax trailii). Song Sparrow (Melospiza melodia) detections declined by a smaller margin. Changes in number of detections for these species did not reflect trends in mesic shrub volume, which had been identified as a likely driver of obligate species abundance by Sanders and Edge but remained relatively unchanged between study periods. Declines of all three focal species reflected regional Breeding Bird Survey trends, corroborating our finding that their declines may not be a result of changes in local site conditions. Compositional similarity between avian communities was significantly higher in 2014 than in 1993-1994, exhibiting a shift toward greater homogenization between structurally distinct riparian habitats. Our results suggest managing working lands for riparian shrub cover or volume, an important metric of grazing intensity and riparian system health, may not be enough to conserve diversity and abundance of riparian-shrub dependent birds, and more work should be done to identify and alleviate factors contributing to these species' declines. Close