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

  Jess Wenick and Chad Karges of Malheur National Wildlife Refuge (MNWR) provided guidance, logistical support, and funding to The Wetlands Conservancy (TWC) for this project. Esther Lev of TWC coordinated ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Jess Wenick and Chad Karges of Malheur National Wildlife Refuge (MNWR) provided guidance, logistical support, and funding to The Wetlands Conservancy (TWC) for this project. Esther Lev of TWC coordinated the project and provided guidance as a member of the Ecology Woring Group (EWG). Vegetation sampling was done by Bruce Newhouse, Richard Brainerd, Jess Wenick, and Barry Smith. Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Jess Wenick and Chad Karges of Malheur National Wildlife Refuge (MNWR) provided guidance, logistical support, and funding to The Wetlands Conservancy (TWC) for this project. Esther Lev of TWC coordinated the project and provided guidance as a member of the Ecology Woring Group (EWG). Vegetation sampling was done by Bruce Newhouse, Richard Brainerd, Jess Wenick, and Barry Smith. Close

• 132. [Article] An Experimental Investigation of Nest Reuse and Nest Site Selection in an Open-Cup Nesting Passerine

  Eastern Kingbirds (Tyrannus tyrannus) breed from coast to coast in North America and build open-cup nests in trees. They have been extensively studied across most of their range and have only on occasion ...

  Citation × Citation Citation Abstract Copy Title: An Experimental Investigation of Nest Reuse and Nest Site Selection in an Open-Cup Nesting Passerine Author: Cancellieri, Sarah A. Year: 2013 Eastern Kingbirds (Tyrannus tyrannus) breed from coast to coast in North America and build open-cup nests in trees. They have been extensively studied across most of their range and have only on occasion been documented to reuse a nest from a previous season. However, at Malheur National Wildlife Refuge (MNWR), located in southeastern Oregon, ~10 % of female Eastern Kingbirds reuse old nests of mainly American Robins (Turdus migratorius). In an attempt to address why nest reuse is so common at MNWR, I used artificial nests to evaluate two hypotheses as to why nest reuse is common in this breeding population. The first hypothesis states that Eastern Kingbirds reuse nests to save time and/or energy (TES) and the second one states nest reuse occurs because there is a shortage of suitable nest sites (NSS). I was able to reject the TES hypothesis because artificial nests provided no apparent reproductive benefits to Eastern Kingbirds, except that if a nest had failed it took less time to lay a replacement clutch after an initial failure if an artificial nest was used instead of building a new nest. A more reasonable explanation is that Eastern Kingbirds face a limited availability of suitable nest sites. With this in mind, I took vegetation measurements to address the hypothesis that Eastern Kingbirds make adaptive choices when selecting a nest site, in which case they would choose sites that increase their probability of breeding successfully. Successful nests, both natural and artificial, were placed higher in a tree and on a steeper angled nest branch than their failed counterparts. Those findings suggest that Eastern Kingbirds make adaptive choices when selecting a nest site. Title: An Experimental Investigation of Nest Reuse and Nest Site Selection in an Open-Cup Nesting Passerine Author: Cancellieri, Sarah A. Year: 2013 Eastern Kingbirds (Tyrannus tyrannus) breed from coast to coast in North America and build open-cup nests in trees. They have been extensively studied across most of their range and have only on occasion been documented to reuse a nest from a previous season. However, at Malheur National Wildlife Refuge (MNWR), located in southeastern Oregon, ~10 % of female Eastern Kingbirds reuse old nests of mainly American Robins (Turdus migratorius). In an attempt to address why nest reuse is so common at MNWR, I used artificial nests to evaluate two hypotheses as to why nest reuse is common in this breeding population. The first hypothesis states that Eastern Kingbirds reuse nests to save time and/or energy (TES) and the second one states nest reuse occurs because there is a shortage of suitable nest sites (NSS). I was able to reject the TES hypothesis because artificial nests provided no apparent reproductive benefits to Eastern Kingbirds, except that if a nest had failed it took less time to lay a replacement clutch after an initial failure if an artificial nest was used instead of building a new nest. A more reasonable explanation is that Eastern Kingbirds face a limited availability of suitable nest sites. With this in mind, I took vegetation measurements to address the hypothesis that Eastern Kingbirds make adaptive choices when selecting a nest site, in which case they would choose sites that increase their probability of breeding successfully. Successful nests, both natural and artificial, were placed higher in a tree and on a steeper angled nest branch than their failed counterparts. Those findings suggest that Eastern Kingbirds make adaptive choices when selecting a nest site. Close

• 133. [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

• 134. [Article] Small mammal and bird abundance in relation to post-fire habitat succession in mountain big sagebrush (Artemisia tridentata ssp. vaseyana) communities

  Fire is an important disturbance mechanism in big sagebrush (Artemisia tridentata) communities, yet little is known about wildlife population dynamics during post-fire habitat succession. I estimated the ...

  Citation × Citation Citation Abstract Copy Title: Small mammal and bird abundance in relation to post-fire habitat succession in mountain big sagebrush (Artemisia tridentata ssp. vaseyana) communities Author: Holmes, Aaron L. Fire is an important disturbance mechanism in big sagebrush (Artemisia tridentata) communities, yet little is known about wildlife population dynamics during post-fire habitat succession. I estimated the abundance of small mammals and birds in relation to fire history in mountain big sagebrush (A.t. spp. vaseyana) communities on the Sheldon National Wildlife Refuge in the northwestern Great Basin, USA. I employed a chronosequence approach that took advantage of multiple wildfires that had occurred in similar plant communities between 7 to 20 years prior to sampling. Belding’s ground squirrel (Spermophilus beldingii) were approximately 10 times as abundant in burned areas relative to adjacent unburned habitat regardless of the number of years since a burn occurred. Deer mouse (Peromyscus maniculatus) was more abundant on more recently burned sites, but not at sites closer to full vegetation recovery. Great basin pocket mouse (Perognathus parvus), sagebrush vole (Lemmiscus curtatus), and least chipmunk (Tamius minimus) abundance did not vary as a function of fire history, but some variance was explained by habitat features such as rocky areas and the canopy characteristics of sagebrush. Bird diversity was higher in unburned habitats irrespective of the number of years of recovery out to 20 years. Nine of the 12 most widely occurring species of birds in the study have population densities influenced by fire or post-fire habitat succession to at least 13 to 20 years following a burn. Sage Sparrow (Amphispiza belli), Black-throated Sparrow (Amphispiza bilineata), and Spotted Towhee (Pipilo maculatus) occurred at relatively low densities and were nearly restricted to unburned habitats. Green-tailed Towhee (Pipilo Chlorurus), Gray Flycatcher (Empidonax wrightii), American Robin (Turdus migratorius), and Brown-headed Cowbird (Molothus ater) occurred at lower densities in burned areas than adjacent unburned areas although the relationship was not strong for the latter two species. The magnitude of the difference in density between burned and unburned sites within a landscape diminished with the number of years of vegetation recovery for Green-tailed Towhee. Brewer’s Sparrow (Spizella brewerii) occurred at lower densities relative to adjacent habitat in the most recent burn, but occurred at higher densities after 20 years of habitat succession, suggesting a positive response with a multiple decade lag period. Horned Lark (Eremophila alpestris) and Vesper Sparrow (Pooecetes gramineus) respond positively to fire, but densities were similar to unburned areas after 20 years of habitat succession. An ordination analysis captured 86% of the variation in 12 bird species with 3 orthogonal axes. My research demonstrates that strong community structure exists for birds associated with mountain big sagebrush habitats, and that fire influences community structure for multiple decades. Title: Small mammal and bird abundance in relation to post-fire habitat succession in mountain big sagebrush (Artemisia tridentata ssp. vaseyana) communities Author: Holmes, Aaron L. Fire is an important disturbance mechanism in big sagebrush (Artemisia tridentata) communities, yet little is known about wildlife population dynamics during post-fire habitat succession. I estimated the abundance of small mammals and birds in relation to fire history in mountain big sagebrush (A.t. spp. vaseyana) communities on the Sheldon National Wildlife Refuge in the northwestern Great Basin, USA. I employed a chronosequence approach that took advantage of multiple wildfires that had occurred in similar plant communities between 7 to 20 years prior to sampling. Belding’s ground squirrel (Spermophilus beldingii) were approximately 10 times as abundant in burned areas relative to adjacent unburned habitat regardless of the number of years since a burn occurred. Deer mouse (Peromyscus maniculatus) was more abundant on more recently burned sites, but not at sites closer to full vegetation recovery. Great basin pocket mouse (Perognathus parvus), sagebrush vole (Lemmiscus curtatus), and least chipmunk (Tamius minimus) abundance did not vary as a function of fire history, but some variance was explained by habitat features such as rocky areas and the canopy characteristics of sagebrush. Bird diversity was higher in unburned habitats irrespective of the number of years of recovery out to 20 years. Nine of the 12 most widely occurring species of birds in the study have population densities influenced by fire or post-fire habitat succession to at least 13 to 20 years following a burn. Sage Sparrow (Amphispiza belli), Black-throated Sparrow (Amphispiza bilineata), and Spotted Towhee (Pipilo maculatus) occurred at relatively low densities and were nearly restricted to unburned habitats. Green-tailed Towhee (Pipilo Chlorurus), Gray Flycatcher (Empidonax wrightii), American Robin (Turdus migratorius), and Brown-headed Cowbird (Molothus ater) occurred at lower densities in burned areas than adjacent unburned areas although the relationship was not strong for the latter two species. The magnitude of the difference in density between burned and unburned sites within a landscape diminished with the number of years of vegetation recovery for Green-tailed Towhee. Brewer’s Sparrow (Spizella brewerii) occurred at lower densities relative to adjacent habitat in the most recent burn, but occurred at higher densities after 20 years of habitat succession, suggesting a positive response with a multiple decade lag period. Horned Lark (Eremophila alpestris) and Vesper Sparrow (Pooecetes gramineus) respond positively to fire, but densities were similar to unburned areas after 20 years of habitat succession. An ordination analysis captured 86% of the variation in 12 bird species with 3 orthogonal axes. My research demonstrates that strong community structure exists for birds associated with mountain big sagebrush habitats, and that fire influences community structure for multiple decades. Close

• 135. [Image] Wholesale waterfowl destruction in the Klamath Country

  	Manuscript discusses how the waterfowl in Klamath country are now protected from hunters by game laws. The Bureau of Reclamation destroyed areas of sanctuary for waterfowl because the demand for land for ...
  	Citation × Citation Citation Abstract Copy Title: Wholesale waterfowl destruction in the Klamath Country Author: Finley, William L. (William Lovell), 1876-1953 Year: 1930 Manuscript discusses how the waterfowl in Klamath country are now protected from hunters by game laws. The Bureau of Reclamation destroyed areas of sanctuary for waterfowl because the demand for land for agricultural use was so high. According to Dr. C. F. Marbut from the Department of Agriculture, the soil from the land in and around the bed of the Lower Klamath Lake could not support agricultural means successfully. Instead, the area became a refuge similar to Clear Lake. Title: Wholesale waterfowl destruction in the Klamath Country Author: Finley, William L. (William Lovell), 1876-1953 Year: 1930 Manuscript discusses how the waterfowl in Klamath country are now protected from hunters by game laws. The Bureau of Reclamation destroyed areas of sanctuary for waterfowl because the demand for land for agricultural use was so high. According to Dr. C. F. Marbut from the Department of Agriculture, the soil from the land in and around the bed of the Lower Klamath Lake could not support agricultural means successfully. Instead, the area became a refuge similar to Clear Lake. Close

• 136. [Image] Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge

  	P12-200-2771NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro
  	Citation × Citation Citation Abstract Copy Title: Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2771NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Title: Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2771NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Close

• 137. [Image] Wild ducks and geese over Tulelake Sump in the Wildlife Refuge

  	P12-200-2772NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro
  	Citation × Citation Citation Abstract Copy Title: Wild ducks and geese over Tulelake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2772NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Title: Wild ducks and geese over Tulelake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2772NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Close

• 138. [Image] Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge

  	P12-200-2773NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro
  	Citation × Citation Citation Abstract Copy Title: Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2773NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Title: Wild ducks and geese over Tule Lake Sump in the Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2773NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Close

• 139. [Image] Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge

  	P12-200-2774NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro
  	Citation × Citation Citation Abstract Copy Title: Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2774NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Title: Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2774NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Close

• 140. [Image] Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge

  	P12-200-2775NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro
  	Citation × Citation Citation Abstract Copy Title: Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2775NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Title: Wild ducks and geese over barley fields in the Tule Lake Wildlife Refuge Author: United States. Bureau of Reclamation, D'Alessandro, A.G. Year: 1964, 2008, 2006 P12-200-2775NA Klamath Project, Region 2, Oregon-California; October 21, 1964; Bureau of Reclamation photo by A. G. D'Alessandro Close