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• 11. [Article] Historical Vegetation of Three Salmon-Bearing Watersheds in the Interior Columbia River Basin

  Land use practices can be a contributing factor to environmental degradation and have been the focus of many ecological studies. One aspect that is less addressed is land use history and the effects that ...

  Citation × Citation Citation Abstract Copy Title: Historical Vegetation of Three Salmon-Bearing Watersheds in the Interior Columbia River Basin Author: Smith, Tyanna Year: 2014 Land use practices can be a contributing factor to environmental degradation and have been the focus of many ecological studies. One aspect that is less addressed is land use history and the effects that past practices, such as logging and grazing, can have on the current landscape. This paper describes research and the synthesis of material on the environmental history and watershed characteristics for three watersheds located within spawning and rearing areas for Chinook salmon in the Grande Ronde River Basin in Northeast Oregon: upper Grande Ronde River, Catherine Creek, and Minam River. The Grande Ronde Basin is critical spawning and rearing habitat for salmonids listed under the Endangered Species Act. The primary historical data sources for reconstructing 19th century stream and riparian conditions are the General Land Office township survey notes from 1863 - 1901. Data about the habitat conditions of the landscape were extracted from notes of each township survey source regarding vegetation, stream crossings, and other features found on the landscape in tabular and spatial forms. Data were organized to describe common stream and riparian conditions for the historical time period using a geographic information system. Watershed basin, Chinook salmon life history, ecoregion and surveyor were analyzed using multivariate techniques to determine which parameters were strongly connected to historical vegetation. Ecoregion had the strongest correlation with plant communities. For future research, these historical data could be compared to current habitat survey data, such as the Oregon Department of Fish & Wildlife’s Aquatic Habitat Inventories, to evaluate the degree of change over time of stream and riparian conditions. Title: Historical Vegetation of Three Salmon-Bearing Watersheds in the Interior Columbia River Basin Author: Smith, Tyanna Year: 2014 Land use practices can be a contributing factor to environmental degradation and have been the focus of many ecological studies. One aspect that is less addressed is land use history and the effects that past practices, such as logging and grazing, can have on the current landscape. This paper describes research and the synthesis of material on the environmental history and watershed characteristics for three watersheds located within spawning and rearing areas for Chinook salmon in the Grande Ronde River Basin in Northeast Oregon: upper Grande Ronde River, Catherine Creek, and Minam River. The Grande Ronde Basin is critical spawning and rearing habitat for salmonids listed under the Endangered Species Act. The primary historical data sources for reconstructing 19th century stream and riparian conditions are the General Land Office township survey notes from 1863 - 1901. Data about the habitat conditions of the landscape were extracted from notes of each township survey source regarding vegetation, stream crossings, and other features found on the landscape in tabular and spatial forms. Data were organized to describe common stream and riparian conditions for the historical time period using a geographic information system. Watershed basin, Chinook salmon life history, ecoregion and surveyor were analyzed using multivariate techniques to determine which parameters were strongly connected to historical vegetation. Ecoregion had the strongest correlation with plant communities. For future research, these historical data could be compared to current habitat survey data, such as the Oregon Department of Fish & Wildlife’s Aquatic Habitat Inventories, to evaluate the degree of change over time of stream and riparian conditions. Close

• 12. [Article] Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region

  This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may ...

  Citation × Citation Citation Abstract Copy Title: Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region Author: Dietrich, Andrew Evans Year: 2012 This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with development in surrounding landscapes were measured in situ. GIS delineation was conducted to define landscape-scale variables at stratified distances from riparian networks up-stream of each site via the utilization of the 2006 NLCD dataset and a finer-scale, regional dataset compiled by the Institute for Natural Resources (INR). Amphibians were detected at seventeen of the thirty-seven sampled streams. The most commonly detected species were Dicamptadon tenebrosus, Plethadon vehiculum and Plethadon dunni. Streams where amphibians were observed had lower average water temperature and conductivity, coarser stream substrate and were located on public property more often than streams where no amphibians were detected. Landscape variables were most significant to amphibians within 100 and 200 meters of the upstream stream network. Occupancy of a site by facultative species was best explained by the proportion of mixed forest in the surrounding watershed (R2=0.343, p<0.001). Occupancy of a stream by obligate species was best predicted by measurements of water quality and in-stream cover (Water Temperature: R2=0.275, p<0.001; Water Conductivity: R2=0.248, p<0.001; Cover: R2=0.323, p<0.001). Occupancy of stream refugia by all observed amphibians was positively influenced by higher percentages of forest cover and lower percentages of urban development and herbaceous vegetation in the surrounding watershed. Results of this study indicate that urban refugia must contain adequate riparian forest area, coarse stream substrate and clean, cool water to sustain stream-amphibian communities. Protection of remnant forested headwater stream networks is essential to the conservation of lotic amphibians in this urbanized region. Title: Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region Author: Dietrich, Andrew Evans Year: 2012 This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with development in surrounding landscapes were measured in situ. GIS delineation was conducted to define landscape-scale variables at stratified distances from riparian networks up-stream of each site via the utilization of the 2006 NLCD dataset and a finer-scale, regional dataset compiled by the Institute for Natural Resources (INR). Amphibians were detected at seventeen of the thirty-seven sampled streams. The most commonly detected species were Dicamptadon tenebrosus, Plethadon vehiculum and Plethadon dunni. Streams where amphibians were observed had lower average water temperature and conductivity, coarser stream substrate and were located on public property more often than streams where no amphibians were detected. Landscape variables were most significant to amphibians within 100 and 200 meters of the upstream stream network. Occupancy of a site by facultative species was best explained by the proportion of mixed forest in the surrounding watershed (R2=0.343, p<0.001). Occupancy of a stream by obligate species was best predicted by measurements of water quality and in-stream cover (Water Temperature: R2=0.275, p<0.001; Water Conductivity: R2=0.248, p<0.001; Cover: R2=0.323, p<0.001). Occupancy of stream refugia by all observed amphibians was positively influenced by higher percentages of forest cover and lower percentages of urban development and herbaceous vegetation in the surrounding watershed. Results of this study indicate that urban refugia must contain adequate riparian forest area, coarse stream substrate and clean, cool water to sustain stream-amphibian communities. Protection of remnant forested headwater stream networks is essential to the conservation of lotic amphibians in this urbanized region. Close

• 13. [Article] Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend

  We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based ...

  Citation × Citation Citation Abstract Copy Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Title: Northwest Forest Plan The First 20 Years (1994-2013): Watershed Condition Status and Trend Author: Miller, Stephanie A., Gordon, Sean N, Eldred, Peter, Beloin, Ronald M., Wilcox, Steve, Raggon, Mark, Andersen, Heidi, Muldoon, Ariel Year: 2015 We used two data sets to evaluate stream and upslope/riparian condition for sixth-field watersheds in each aquatic province within the Northwest Forest Plan (NWFP) area. The stream evaluation was based on stream sampling data collected from 2002 to the 2013 (214 watersheds) as part of an eight year repeating (rotating) sample design. We are currently halfway through our second rotation of stream sampling, and have repeated 110 watersheds since the second rotation began in 2009. The analysis presented in this report uses roughly half the number of watersheds as was originally intended by the sample design since re-visitation will not be completed until 2017. In the meantime, we compare the first rotation of visits (2002-2009) to the first four years of the second rotation (2010-2013) giving us a general idea of current patterns. To evaluate stream condition we used a reference condition nearest neighbor statistical approach to calculate the stream physical habitat scores based on substrate, wood, and pool metrics for each watershed. Macroinvertebrates and water temperature were analyzed separately from physical habitat and provide additional assessment of overall watershed condition. Scores for both stream and upslope/riparian conditions were normalized to fall between 0 (poor) and 100 (good). Close

• 14. [Article] Bird use of revetted riverbanks in the Willamette Valley

  Over 115 miles of rock revetments that serve to protect river banks have been constructed in the Willamette Basin. In this study the spring and summer bird use of Willamette Basin revetments is examined. ...

  Citation × Citation Citation Abstract Copy Title: Bird use of revetted riverbanks in the Willamette Valley Author: Perry, Clifford Brian Year: 1977 Over 115 miles of rock revetments that serve to protect river banks have been constructed in the Willamette Basin. In this study the spring and summer bird use of Willamette Basin revetments is examined. Revetments that had not been recently cleared of most woody vegetation and blackberries were found to have significantly greater total and breeding bird use than cleared revetments. Possible factors affecting bird use, such as vegetation on revetments and vegetation adjacent to revetments are examined using linear regression analysis. The results of this study are compared with results of previous work in riparian forests along the Columbia River. It is concluded that revetments represent significant avian habitat, especially for "edge species," and that present maintenance practices involving removal of vegetation adversely affect bird use. Title: Bird use of revetted riverbanks in the Willamette Valley Author: Perry, Clifford Brian Year: 1977 Over 115 miles of rock revetments that serve to protect river banks have been constructed in the Willamette Basin. In this study the spring and summer bird use of Willamette Basin revetments is examined. Revetments that had not been recently cleared of most woody vegetation and blackberries were found to have significantly greater total and breeding bird use than cleared revetments. Possible factors affecting bird use, such as vegetation on revetments and vegetation adjacent to revetments are examined using linear regression analysis. The results of this study are compared with results of previous work in riparian forests along the Columbia River. It is concluded that revetments represent significant avian habitat, especially for "edge species," and that present maintenance practices involving removal of vegetation adversely affect bird use. Close

• 15. [Article] Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy

  As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial ...

  Citation × Citation Citation Abstract Copy Title: Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy Author: Burcsu, Theresa, Kagan, James S. Year: 2011 As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial modeling to identify conservation opportunity areas (COAs). To complete the project, INR analysts proposed a strategy that would map high value areas using a landscape approach that is focused on relatively high spatial resolution data sets available for the whole metropolitan region. The approach creates 2 main metrics: one focused on terrestrial organisms and the other focused on aquatic and riparian organisms. These are combined to create a map of highly ranked land areas that can be used to formulate a map of conservation opportunity areas. The purpose of the COA mapping project was to use geographic information system methods to identify landscape patches with conservation and restoration potential. The criteria used to identify these high value patches was based on a number of base- and derived-data sets that we call “data inputs.” The data ranged from recently mapped land use and land cover types, hydrological data to indicate species habitat requirements, and road influence on habitat patches. The project identified some areas in which data gaps exist (e.g., region-wide biodiversity data collected and mapped in consistent ways) and some opportunities for improving existent data sets (e.g., land use/land cover map). The project provided several layers that can be used to guide the final Regional Conservation Strategy in selecting conservation opportunity areas. The best layer will depend upon the needs of the RCS efforts, however, in our opinion the most appropriate layer to use is COA 3.11.1 which weights wetlands fairly high, but not as highly as the second data draft. COA 3.10.1 offers similar results as well. Overall it appears that the model results corroborate corridors analysis done previously (Hennings and Soll 2010). There are some issues remaining that we feel can most adequately be addressed by updating the base land use/land cover map. Title: Mapping Conservation Opportunity Areas for the Intertwine's Regional Conservation Strategy Author: Burcsu, Theresa, Kagan, James S. Year: 2011 As part of efforts to develop the Regional Conservation Strategy (RCS) for the greater Portland-Vancouver region, Oregon State University’s Institute for Natural Resources (INR) was asked to use spatial modeling to identify conservation opportunity areas (COAs). To complete the project, INR analysts proposed a strategy that would map high value areas using a landscape approach that is focused on relatively high spatial resolution data sets available for the whole metropolitan region. The approach creates 2 main metrics: one focused on terrestrial organisms and the other focused on aquatic and riparian organisms. These are combined to create a map of highly ranked land areas that can be used to formulate a map of conservation opportunity areas. The purpose of the COA mapping project was to use geographic information system methods to identify landscape patches with conservation and restoration potential. The criteria used to identify these high value patches was based on a number of base- and derived-data sets that we call “data inputs.” The data ranged from recently mapped land use and land cover types, hydrological data to indicate species habitat requirements, and road influence on habitat patches. The project identified some areas in which data gaps exist (e.g., region-wide biodiversity data collected and mapped in consistent ways) and some opportunities for improving existent data sets (e.g., land use/land cover map). The project provided several layers that can be used to guide the final Regional Conservation Strategy in selecting conservation opportunity areas. The best layer will depend upon the needs of the RCS efforts, however, in our opinion the most appropriate layer to use is COA 3.11.1 which weights wetlands fairly high, but not as highly as the second data draft. COA 3.10.1 offers similar results as well. Overall it appears that the model results corroborate corridors analysis done previously (Hennings and Soll 2010). There are some issues remaining that we feel can most adequately be addressed by updating the base land use/land cover map. Close

• 16. [Article] Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon

  We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of ...

  Citation × Citation Citation Abstract Copy Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Close

• 17. [Article] Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures

  Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each ...

  Citation × Citation Citation Abstract Copy Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Close

• 18. [Article] Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint?

  The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. ...

  Citation × Citation Citation Abstract Copy Title: Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint? Author: Redmond, Lucas J., Murphy, Michael T., Dolan, Amy C. Year: 2007 The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. We report an unusually high rate of nest reuse (~10% of 341 nests) for Eastern Kingbirds (Tyrannus tyrannus) breeding at Malheur National Wildlife Refuge, Oregon. We found no difference in availability of nesting habitat or food abundance in territories in which nests were and were not reused. We also found no support for the hypotheses that kingbirds benefited from nest reuse by breeding earlier, laying larger clutches, or fledging more young, and, contrary to expectations, females that reused nests laid significantly smaller eggs than females who built their own nests. Nest reuse was independent of age: a roughly equal number of females for which we had multiple years of data both reused nests and built new nests, but at different points in their lives. Competition for nest sites seems high at Malheur National Wildlife Refuge because many open-cup nesting species utilize similar nest sites in the limited zone of riparian vegetation. A shortage of high-quality nest sites, coupled with interspecific competition, may underlie the high frequency of nest reuse in this kingbird population. Title: Nest Reuse by Eastern Kingbirds: Adaptive Behavior or Ecological Constraint? Author: Redmond, Lucas J., Murphy, Michael T., Dolan, Amy C. Year: 2007 The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. We report an unusually high rate of nest reuse (~10% of 341 nests) for Eastern Kingbirds (Tyrannus tyrannus) breeding at Malheur National Wildlife Refuge, Oregon. We found no difference in availability of nesting habitat or food abundance in territories in which nests were and were not reused. We also found no support for the hypotheses that kingbirds benefited from nest reuse by breeding earlier, laying larger clutches, or fledging more young, and, contrary to expectations, females that reused nests laid significantly smaller eggs than females who built their own nests. Nest reuse was independent of age: a roughly equal number of females for which we had multiple years of data both reused nests and built new nests, but at different points in their lives. Competition for nest sites seems high at Malheur National Wildlife Refuge because many open-cup nesting species utilize similar nest sites in the limited zone of riparian vegetation. A shortage of high-quality nest sites, coupled with interspecific competition, may underlie the high frequency of nest reuse in this kingbird population. Close

• 19. [Article] Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon

  In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Close

• 20. [Article] Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon

  This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Close