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• 51. [Article] Resilience and Resistance of Sagebrush Ecosystems: Implications for State and Transition Models and Management Treatments

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society ...

  Citation × Citation Citation Abstract Copy Title: Resilience and Resistance of Sagebrush Ecosystems: Implications for State and Transition Models and Management Treatments Author: Chambers, Jeanne C., Board, David I., Schupp, Eugene W., Grace, James B., Roundy, Bruce A., Tausch, Robin J., Pyke, David A., Miller, Richard F. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society for Range Management and can be found at: http://www.bioone.org/loi/rama. Title: Resilience and Resistance of Sagebrush Ecosystems: Implications for State and Transition Models and Management Treatments Author: Chambers, Jeanne C., Board, David I., Schupp, Eugene W., Grace, James B., Roundy, Bruce A., Tausch, Robin J., Pyke, David A., Miller, Richard F. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society for Range Management and can be found at: http://www.bioone.org/loi/rama. Close

• 52. [Article] An Investigation of Infection Mechanisms of Arceuthobium Campylopodum

  Wound periderm is formed by Juniperus occidentalis and Calocedrus decurrens in resistance to infection by the dwarf mistletoe Arceuthobium campylopodum. The pattern of wound periderm formation suggests ...

  Citation × Citation Citation Abstract Copy Title: An Investigation of Infection Mechanisms of Arceuthobium Campylopodum Author: Garcia, Annabella Jaramillo Year: 1974 Wound periderm is formed by Juniperus occidentalis and Calocedrus decurrens in resistance to infection by the dwarf mistletoe Arceuthobium campylopodum. The pattern of wound periderm formation suggests that chemical as well as mechanical factors are involved. The concentration of hydrolases in the radicular apex of the parasite suggests that they may facilitate the penetration process by which dwarf mistletoes infect their hosts. Emzymatic assistance may also provide a partial explanation for the specificity with which dwarf mistletoes are adapted to given hosts. These resistance responses by the the non-host species were compared with the normal infection process Pinus ponderosa. Title: An Investigation of Infection Mechanisms of Arceuthobium Campylopodum Author: Garcia, Annabella Jaramillo Year: 1974 Wound periderm is formed by Juniperus occidentalis and Calocedrus decurrens in resistance to infection by the dwarf mistletoe Arceuthobium campylopodum. The pattern of wound periderm formation suggests that chemical as well as mechanical factors are involved. The concentration of hydrolases in the radicular apex of the parasite suggests that they may facilitate the penetration process by which dwarf mistletoes infect their hosts. Emzymatic assistance may also provide a partial explanation for the specificity with which dwarf mistletoes are adapted to given hosts. These resistance responses by the the non-host species were compared with the normal infection process Pinus ponderosa. Close

• 53. [Article] Long-term Fire Effects on Plant Succession and Exotic Weeds in Protected Area Sagebrush Steppe, John Day Fossil Beds National Monument, Oregon

  The historical function of fire in sagebrush steppe has been altered by 19th century overgrazing, active fire suppression, annual grass invasion and encroachment of woody species. The significance of ...

  Citation × Citation Citation Abstract Copy Title: Long-term Fire Effects on Plant Succession and Exotic Weeds in Protected Area Sagebrush Steppe, John Day Fossil Beds National Monument, Oregon Author: Reed-Dustin, Claire Marie The historical function of fire in sagebrush steppe has been altered by 19th century overgrazing, active fire suppression, annual grass invasion and encroachment of woody species. The significance of fire to these systems is known, but research on long-term fire effects are limited. The Sheep Rock management unit of the John Day Fossil Beds National Monument, Oregon offers an opportunity to study long-term (15 year) responses of Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) communities to fire. Using generalized linear mixed models, this study examined responses of A. tridentata ssp. wyomingensis, Bromus tectorum (cheatgrass), Gutierrezia sarothrae (broom snakeweed), Poa secunda (Sandberg bluegrass), Pseudoroegneria spicata (bluebunch wheatgrass) and Taeniatherum caput-medusae (medusahead), along gradients of community type and topography through time post-fire. Community types were differentiated between A. tridentata ssp. wyomingensis dominant plots (brush plots) and Juniperus occidentalis (western juniper) dominant plots (forest plots). Cover of B. tectorum was greatest in brush plots. Bromus tectorum cover increased dramatically 2 years post-burn. At 5 years post-burn cover of B. tectorum was 135% of pre-burn cover in brush plots and 301% of pre-burn cover in forest plots. Analysis determined abundance of T. caput-medusae was not enough pre-burn to analyze fire effects. Examination of mean T. caput-medusae cover, in plots through time, suggests it is expanding within the Sheep Rock management unit. Pseudoroegneria spicata is more abundant in forest plots than in brush plots. In forest plots, P. spicata cover decreased by 49% 1 year post-burn, but recovered by 5 years post-burn. In brush plots, cover of P. spicata declined, but not significantly through time post-fire. On northern exposures recovery of P. spicata cover occurred between 1 and 2 years post-burn, whereas on southern exposures recovery occurred between 2 and 5 years post-burn. The cover of P. secunda did not show a dramatic response to fire through time post-burn. Fire reduced A. tridentata ssp. wyomingensis cover in brush plots by 99% and 100% on northern and southern exposures, respectively. In forest plots, fire reduced A. tridentata ssp. wyomingensis cover by 86% and 47% on northern and southern exposures, respectively. Similarly, A. tridentata ssp. wyomingensis density in brush plots declined by 96% on both northern and southern exposures 1 year post-fire. In forest plots fire reduced A. tridentata ssp. wyomingensis density by 71% on northern exposures and 0% on southern exposures. The cover and density of A. tridentata ssp. wyomingensis did not change significantly through time after an initial decrease 1 year post-burn, except for density in forest plots, which didn’t show significant change through time. Artemisia tridentata is a long-lived species and therefore continuation of this study is required to gain a fuller perspective on its long term response to fire. Cover of G. sarothrae declined by 92% in brush plots and by 73% in forest plots. Gutierrezia sarothrae cover returned to pre-burn cover by 5 years post burn in brush plots, but did not recover in forest plots. Topography was not identified as a significant parameter for G. sarothrae cover in response to fire. Similarly to G. sarothrae cover, G. sarothrae density decreased 1 year post-burn and recovered by 5 years post burn in brush plots, but it did not recover in forest plots. In contrast to G. sarothrae cover, topography was identified as a significant parameter for the response of G. sarothrae density. We hypothesize south slopes favor G. sarothrae establishment, while north slopes favor increased G. sarothrae size, which explains topographic significance for density, but not for cover. Results of this study can be used by land managers to consider species specific responses to fire in both the short and long-term. This information is useful when developing plans for reintroducing fire into A. tridentata ssp. wyomingensis systems or when developing post-wildfire management strategies. Title: Long-term Fire Effects on Plant Succession and Exotic Weeds in Protected Area Sagebrush Steppe, John Day Fossil Beds National Monument, Oregon Author: Reed-Dustin, Claire Marie The historical function of fire in sagebrush steppe has been altered by 19th century overgrazing, active fire suppression, annual grass invasion and encroachment of woody species. The significance of fire to these systems is known, but research on long-term fire effects are limited. The Sheep Rock management unit of the John Day Fossil Beds National Monument, Oregon offers an opportunity to study long-term (15 year) responses of Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) communities to fire. Using generalized linear mixed models, this study examined responses of A. tridentata ssp. wyomingensis, Bromus tectorum (cheatgrass), Gutierrezia sarothrae (broom snakeweed), Poa secunda (Sandberg bluegrass), Pseudoroegneria spicata (bluebunch wheatgrass) and Taeniatherum caput-medusae (medusahead), along gradients of community type and topography through time post-fire. Community types were differentiated between A. tridentata ssp. wyomingensis dominant plots (brush plots) and Juniperus occidentalis (western juniper) dominant plots (forest plots). Cover of B. tectorum was greatest in brush plots. Bromus tectorum cover increased dramatically 2 years post-burn. At 5 years post-burn cover of B. tectorum was 135% of pre-burn cover in brush plots and 301% of pre-burn cover in forest plots. Analysis determined abundance of T. caput-medusae was not enough pre-burn to analyze fire effects. Examination of mean T. caput-medusae cover, in plots through time, suggests it is expanding within the Sheep Rock management unit. Pseudoroegneria spicata is more abundant in forest plots than in brush plots. In forest plots, P. spicata cover decreased by 49% 1 year post-burn, but recovered by 5 years post-burn. In brush plots, cover of P. spicata declined, but not significantly through time post-fire. On northern exposures recovery of P. spicata cover occurred between 1 and 2 years post-burn, whereas on southern exposures recovery occurred between 2 and 5 years post-burn. The cover of P. secunda did not show a dramatic response to fire through time post-burn. Fire reduced A. tridentata ssp. wyomingensis cover in brush plots by 99% and 100% on northern and southern exposures, respectively. In forest plots, fire reduced A. tridentata ssp. wyomingensis cover by 86% and 47% on northern and southern exposures, respectively. Similarly, A. tridentata ssp. wyomingensis density in brush plots declined by 96% on both northern and southern exposures 1 year post-fire. In forest plots fire reduced A. tridentata ssp. wyomingensis density by 71% on northern exposures and 0% on southern exposures. The cover and density of A. tridentata ssp. wyomingensis did not change significantly through time after an initial decrease 1 year post-burn, except for density in forest plots, which didn’t show significant change through time. Artemisia tridentata is a long-lived species and therefore continuation of this study is required to gain a fuller perspective on its long term response to fire. Cover of G. sarothrae declined by 92% in brush plots and by 73% in forest plots. Gutierrezia sarothrae cover returned to pre-burn cover by 5 years post burn in brush plots, but did not recover in forest plots. Topography was not identified as a significant parameter for G. sarothrae cover in response to fire. Similarly to G. sarothrae cover, G. sarothrae density decreased 1 year post-burn and recovered by 5 years post burn in brush plots, but it did not recover in forest plots. In contrast to G. sarothrae cover, topography was identified as a significant parameter for the response of G. sarothrae density. We hypothesize south slopes favor G. sarothrae establishment, while north slopes favor increased G. sarothrae size, which explains topographic significance for density, but not for cover. Results of this study can be used by land managers to consider species specific responses to fire in both the short and long-term. This information is useful when developing plans for reintroducing fire into A. tridentata ssp. wyomingensis systems or when developing post-wildfire management strategies. Close

• 54. [Article] Assessment of mule deer fawn survival and birth site habitat attributes in south-central Oregon

  Mule deer (Odocoileus hemionus) populations in south-central Oregon are near their lowest levels since census efforts began in 1961. I investigated fawn survival, cause-specific mortality, and factors ...

  Citation × Citation Citation Abstract Copy Title: Assessment of mule deer fawn survival and birth site habitat attributes in south-central Oregon Author: Speten, David Mule deer (Odocoileus hemionus) populations in south-central Oregon are near their lowest levels since census efforts began in 1961. I investigated fawn survival, cause-specific mortality, and factors contributing to mortality from 2010 – 2012 to identify potential causes for the decline. I also explored pre-parturition and parturition site characteristics. I studied fawn survival among two different population segments in south-central Oregon. Adult females (n = 126; > 1 year old) were captured on winter ranges to collect biological samples and attach transmitters. Vaginal implant transmitters facilitated the capture of fawns (n = 127). Fawns (birth to < 1 year old) were radio-collared and mortalities investigated. Fawns died primarily as a result of predation, but other sources of mortality included vehicle collisions, fence entanglement, hunter harvest, drowning, disease, and unknown causes. Predation was primarily attributed to coyotes (Canis latrans) but bears (Ursus americanus), cougars (Puma concolor), and bobcats (Lynx rufus) also preyed on study animals. To investigate survival, I developed known-fate models within Program MARK using 9 individual covariates and 3 environmental covariates. Estimated annual fawn survival was 34% and positively correlated with a linear time trend. Survival was not correlated with indicators of female body condition including rump fat, blood serum non-esterified fatty acids, blood serum triglycerides, and blood serum β-hydroxybutyrate. Survival did not differ by fawn sex, fawn weight, date of birth, wintering area, or whole blood selenium levels. Environmental covariates including precipitation, year, and temperature did not significantly explain fawn survival. I concluded that predation might be limiting mule deer population growth in south-central Oregon. However, I did not explore the full suite of factors that would indicate sources of population regulation. I also investigated adult female habitat use prior to and during parturition from 2010 – 2013. I measured 10 habitat attributes at all parturition sites for comparison to randomly selected pre-parturition locations within each adult female’s seasonal range. Birth sites that occurred in habitats characterized by juniper (Juniperus occidentalis), were closer to water and within greater vegetative cover compared to summer range sites in the same habitat type. Other birth sites were located in areas characterized by conifer spp. (Abies concolor, Pinus spp., Pseudotsuga menziesii) and in these areas there were no differences in habitat attributes between birth sites and summer range sites. I concluded that within each habitat type birth sites might be chosen to maximize predator avoidance and within juniper habitats low water resources might contribute to site selection. Title: Assessment of mule deer fawn survival and birth site habitat attributes in south-central Oregon Author: Speten, David Mule deer (Odocoileus hemionus) populations in south-central Oregon are near their lowest levels since census efforts began in 1961. I investigated fawn survival, cause-specific mortality, and factors contributing to mortality from 2010 – 2012 to identify potential causes for the decline. I also explored pre-parturition and parturition site characteristics. I studied fawn survival among two different population segments in south-central Oregon. Adult females (n = 126; > 1 year old) were captured on winter ranges to collect biological samples and attach transmitters. Vaginal implant transmitters facilitated the capture of fawns (n = 127). Fawns (birth to < 1 year old) were radio-collared and mortalities investigated. Fawns died primarily as a result of predation, but other sources of mortality included vehicle collisions, fence entanglement, hunter harvest, drowning, disease, and unknown causes. Predation was primarily attributed to coyotes (Canis latrans) but bears (Ursus americanus), cougars (Puma concolor), and bobcats (Lynx rufus) also preyed on study animals. To investigate survival, I developed known-fate models within Program MARK using 9 individual covariates and 3 environmental covariates. Estimated annual fawn survival was 34% and positively correlated with a linear time trend. Survival was not correlated with indicators of female body condition including rump fat, blood serum non-esterified fatty acids, blood serum triglycerides, and blood serum β-hydroxybutyrate. Survival did not differ by fawn sex, fawn weight, date of birth, wintering area, or whole blood selenium levels. Environmental covariates including precipitation, year, and temperature did not significantly explain fawn survival. I concluded that predation might be limiting mule deer population growth in south-central Oregon. However, I did not explore the full suite of factors that would indicate sources of population regulation. I also investigated adult female habitat use prior to and during parturition from 2010 – 2013. I measured 10 habitat attributes at all parturition sites for comparison to randomly selected pre-parturition locations within each adult female’s seasonal range. Birth sites that occurred in habitats characterized by juniper (Juniperus occidentalis), were closer to water and within greater vegetative cover compared to summer range sites in the same habitat type. Other birth sites were located in areas characterized by conifer spp. (Abies concolor, Pinus spp., Pseudotsuga menziesii) and in these areas there were no differences in habitat attributes between birth sites and summer range sites. I concluded that within each habitat type birth sites might be chosen to maximize predator avoidance and within juniper habitats low water resources might contribute to site selection. Close

• 55. [Article] Food selection and juvenile survival in Nuttall's cottontails in central Oregon

  A population of Nuttall's cottontails (Sylvilagus nuttallii) in Deschutes County, Oregon, decreased fromm 166 individuals in August 1978 to 76 individuals in August 1979. Survival rates of four annual ...

  Citation × Citation Citation Abstract Copy Title: Food selection and juvenile survival in Nuttall's cottontails in central Oregon Author: Hundertmark, Kris Joseph A population of Nuttall's cottontails (Sylvilagus nuttallii) in Deschutes County, Oregon, decreased fromm 166 individuals in August 1978 to 76 individuals in August 1979. Survival rates of four annual litter groups in 1978 were 0.74, 0.35, 0.72, and 0.93; survival rates for the same litter groups, respectively, in 1979 were 0.12, 0.28, 0.07, and 0.18. Population density and juvenile survival decreased between the 2 years possibly because of alterations in forage quality and quantity caused by precipitation. Numbers of cottontails on the study area on 30 August were related significantly (P<0.O1) to initial breeding density and to precipitation falling during the breeding season (February - July). Survival in juvenile cottontails from birth to 30 August was related significantly to precipitation in the first (P<O.05), third (P<O.01), and fourth (p<0.O1) annual litter groups. Vegetative abundance at the end of the growing season (September) decreased by approximately 30% between the 2 years; the decline corresponded with a 45% decrease in crop-year (September - June) precipitation. Succulence of grasses, forbs, and shrubs was greatest in spring, declined in summer, and increased slightly in late summer. Forbs consistently were the most succulent group, except in September when shrubs were most succulent. Grasses exhibited the greatest variation in succulence in response to precipitation; shrubs exhibited the least. A moisture availability index (MAI) indicated that, despite approximately equal estimates of succulence between the 2 years, moisture was more available to cottontails in 1978 because of greater abundance of vegetation. Cottontails seemingly selected forage groups in relation to their relative succulence, within limits. Shrubs were avoided, and succulent juniper (Juniperus occidentalis) foliage was eaten only in dry periods, possibly because of low tolerance in cottontails to plant secondary compounds, particularly terpenoids. Juveniles selected forbs in significantly (P<0.05) greater proportions than adults, possibly to aquire additional moisture for growth; diets of younger (<600 g) and older (>600 g) juveniles did not differ. Breeding females selected forbs in significantly (P<0.05) greater proportions than males, possibly because of moisture demands associated with reproduction and lactation. Other nutrients, especially protein, that are associated with moisture content of plants, possibly were as important as moisture in determining food habits and population fluctuations in Nuttall's cottontails in central Oregon. The relationship between juvenile survival and precipitation possibly was caused by genotypic variation in efficiency in cottontails to utilize moisture and nutrients. Title: Food selection and juvenile survival in Nuttall's cottontails in central Oregon Author: Hundertmark, Kris Joseph A population of Nuttall's cottontails (Sylvilagus nuttallii) in Deschutes County, Oregon, decreased fromm 166 individuals in August 1978 to 76 individuals in August 1979. Survival rates of four annual litter groups in 1978 were 0.74, 0.35, 0.72, and 0.93; survival rates for the same litter groups, respectively, in 1979 were 0.12, 0.28, 0.07, and 0.18. Population density and juvenile survival decreased between the 2 years possibly because of alterations in forage quality and quantity caused by precipitation. Numbers of cottontails on the study area on 30 August were related significantly (P<0.O1) to initial breeding density and to precipitation falling during the breeding season (February - July). Survival in juvenile cottontails from birth to 30 August was related significantly to precipitation in the first (P<O.05), third (P<O.01), and fourth (p<0.O1) annual litter groups. Vegetative abundance at the end of the growing season (September) decreased by approximately 30% between the 2 years; the decline corresponded with a 45% decrease in crop-year (September - June) precipitation. Succulence of grasses, forbs, and shrubs was greatest in spring, declined in summer, and increased slightly in late summer. Forbs consistently were the most succulent group, except in September when shrubs were most succulent. Grasses exhibited the greatest variation in succulence in response to precipitation; shrubs exhibited the least. A moisture availability index (MAI) indicated that, despite approximately equal estimates of succulence between the 2 years, moisture was more available to cottontails in 1978 because of greater abundance of vegetation. Cottontails seemingly selected forage groups in relation to their relative succulence, within limits. Shrubs were avoided, and succulent juniper (Juniperus occidentalis) foliage was eaten only in dry periods, possibly because of low tolerance in cottontails to plant secondary compounds, particularly terpenoids. Juveniles selected forbs in significantly (P<0.05) greater proportions than adults, possibly to aquire additional moisture for growth; diets of younger (<600 g) and older (>600 g) juveniles did not differ. Breeding females selected forbs in significantly (P<0.05) greater proportions than males, possibly because of moisture demands associated with reproduction and lactation. Other nutrients, especially protein, that are associated with moisture content of plants, possibly were as important as moisture in determining food habits and population fluctuations in Nuttall's cottontails in central Oregon. The relationship between juvenile survival and precipitation possibly was caused by genotypic variation in efficiency in cottontails to utilize moisture and nutrients. Close

• 56. [Article] Bird and rodent nesting in excavated cavities in Pinon-juniper woodland, southeastern Colorado

  I studied bird and rodent nesting in woodpecker-excavated cavities in pifion-juniper (Pinus edulis-Juniperus monosperma) (P-J) woodland in southeastern Colorado during the spring and summer of 1987 and ...

  Citation × Citation Citation Abstract Copy Title: Bird and rodent nesting in excavated cavities in Pinon-juniper woodland, southeastern Colorado Author: Youkey, Donald E. I studied bird and rodent nesting in woodpecker-excavated cavities in pifion-juniper (Pinus edulis-Juniperus monosperma) (P-J) woodland in southeastern Colorado during the spring and summer of 1987 and 1988. Two related investigations were conducted: one described characteristics of habitat used by birds and rodents nesting in woodpecker-excavated cavities and the other evaluated whether or not birds and rodents were competing for the nest-cavity resource. Seven species of birds and 4 species of rodents were included in the study: American kestrel (Falco sparverius), western screech-owl (Otus kennicottii), northern flicker (Colaptus auratus), ash-throated flycatcher (Mviarchus cinerascens), plain titmouse (Parus inornatus), Bewick's wren (Thrvothorus bewickii), mountain bluebird (Sialia currucoides), white-footed mouse (Peromvscus leucopus), deer mouse (P. maniculatus), pition mouse (P. truei), and woodrat (Neotoma spp.). 1987 was a preliminary year. In 1988, 248 nests were located in 433 cavities monitored, and cavity density averaged 1.5/ha. Western screech-owls nested earlier than all other species (P < 0.001), plain titmice nested earlier than ash-throated flycatchers (P = 0.033), and other species of birds and rodents nested at the same time (P < 0.05). Seven of 19 characteristics associated with nests differed (P < 0.05) among species: 4 of 5 at the cavity-level, 2 of 5 at the cavity-tree level, and 1 of 9 at the cavity-site level. Generally, larger species (kestrels, screech-owls, and flickers) nested in larger cavities and smaller species (white-footed, deer, and pitlon mice, and Bewick's wren) nested in smaller cavities. Characteristics of cavities used for nesting by secondary cavity-nesting species also differed from characteristics of all cavities monitored most frequently on characteristics associated with cavity size. Differences were demonstrated using univariate analysis (Kruskal-Wallis ANOVA) because with the considerable overlap among species, multivariate analysis (discriminant function analysis [DFA]) could not discriminate among species. Management implications include the need to evaluate impacts to the P-J woodland cavity-nesting community before converting the woodland to rangeland, evaluate impacts of logging in higher elevation forests where many of the cavity-excavating woodpeckers breed, and evaluate the influence of the nest-parasitic brown-headed cowbird (Molothrus ater) and the highly competitive European starling (Sturnus vulqaris). In 1988, 95 cavities were manipulated to yield 47 rodent exclusions and 48 bird exclusions. Proportions of these manipulated cavities used for nesting by birds and rodents were compared to the proportions of 83 control cavities used for nesting by the appropriate group of species. Cavities were revisited at 10-day intervals 4 May - 6 August 1988 and evidence of use recorded. The proportions of cavities used as nests by rodents was significantly greater in manipulated cavities than in control cavities (P = 0.0083). Thus, interspecific competition was experimentally demonstrated between birds and rodents for nest-sites in woodpecker-excavated cavities. Title: Bird and rodent nesting in excavated cavities in Pinon-juniper woodland, southeastern Colorado Author: Youkey, Donald E. I studied bird and rodent nesting in woodpecker-excavated cavities in pifion-juniper (Pinus edulis-Juniperus monosperma) (P-J) woodland in southeastern Colorado during the spring and summer of 1987 and 1988. Two related investigations were conducted: one described characteristics of habitat used by birds and rodents nesting in woodpecker-excavated cavities and the other evaluated whether or not birds and rodents were competing for the nest-cavity resource. Seven species of birds and 4 species of rodents were included in the study: American kestrel (Falco sparverius), western screech-owl (Otus kennicottii), northern flicker (Colaptus auratus), ash-throated flycatcher (Mviarchus cinerascens), plain titmouse (Parus inornatus), Bewick's wren (Thrvothorus bewickii), mountain bluebird (Sialia currucoides), white-footed mouse (Peromvscus leucopus), deer mouse (P. maniculatus), pition mouse (P. truei), and woodrat (Neotoma spp.). 1987 was a preliminary year. In 1988, 248 nests were located in 433 cavities monitored, and cavity density averaged 1.5/ha. Western screech-owls nested earlier than all other species (P < 0.001), plain titmice nested earlier than ash-throated flycatchers (P = 0.033), and other species of birds and rodents nested at the same time (P < 0.05). Seven of 19 characteristics associated with nests differed (P < 0.05) among species: 4 of 5 at the cavity-level, 2 of 5 at the cavity-tree level, and 1 of 9 at the cavity-site level. Generally, larger species (kestrels, screech-owls, and flickers) nested in larger cavities and smaller species (white-footed, deer, and pitlon mice, and Bewick's wren) nested in smaller cavities. Characteristics of cavities used for nesting by secondary cavity-nesting species also differed from characteristics of all cavities monitored most frequently on characteristics associated with cavity size. Differences were demonstrated using univariate analysis (Kruskal-Wallis ANOVA) because with the considerable overlap among species, multivariate analysis (discriminant function analysis [DFA]) could not discriminate among species. Management implications include the need to evaluate impacts to the P-J woodland cavity-nesting community before converting the woodland to rangeland, evaluate impacts of logging in higher elevation forests where many of the cavity-excavating woodpeckers breed, and evaluate the influence of the nest-parasitic brown-headed cowbird (Molothrus ater) and the highly competitive European starling (Sturnus vulqaris). In 1988, 95 cavities were manipulated to yield 47 rodent exclusions and 48 bird exclusions. Proportions of these manipulated cavities used for nesting by birds and rodents were compared to the proportions of 83 control cavities used for nesting by the appropriate group of species. Cavities were revisited at 10-day intervals 4 May - 6 August 1988 and evidence of use recorded. The proportions of cavities used as nests by rodents was significantly greater in manipulated cavities than in control cavities (P = 0.0083). Thus, interspecific competition was experimentally demonstrated between birds and rodents for nest-sites in woodpecker-excavated cavities. Close

• 57. [Article] Ecological effects of spring and fall prescribed burning on basin big sagebrush : Idaho fescue--bluebunch wheatgrass communities

  The vegetation response of spring and fall prescribed fires in basin big sagebrush (Artemisia tridentata subsp. tridentata Nutt.)/Idaho fescue (Festuca idahoensis Elmer)--bluebunch wheatgrass (Agropyron ...

  Citation × Citation Citation Abstract Copy Title: Ecological effects of spring and fall prescribed burning on basin big sagebrush : Idaho fescue--bluebunch wheatgrass communities Author: Sapsis, David B. The vegetation response of spring and fall prescribed fires in basin big sagebrush (Artemisia tridentata subsp. tridentata Nutt.)/Idaho fescue (Festuca idahoensis Elmer)--bluebunch wheatgrass (Agropyron spicatum Pursh. (Scribn. & Smith)) communities was measured at the John Day Fossil Beds National Monument in eastern Oregon. Objectives of the study were to quantify fuel loads, environmental conditions, fire behavior and vegetation response corresponding to these two fire treatments. Pretreatment fuel loads in the experimental units ranged from 5 to 12 Mg/ha, with the fall treatment units averaging 10.5 Mg/ha, and the spring units averaging 6.2 Mg/ha. Both treatments contained large amounts (> 3 Mg/ha) of herbaceous fuels. Moisture content of grass and herb fuels were significantly greater in the spring burned units. This is believed to be largely responsible for the less severe fire behavior observed in the spring burn treatment. Flame lengths averaged 4.2 m in fall burns, compared to a mean of 1.7 m in the spring plots. Similarly, rate of spread was significantly greater in the fall units, averaging 1.6 m/s, compared to 0.2 m/s in the spring treatment. Fireline Intensity was seven times greater, and total energy release was twice was great in the fall burns. Neither burn treatment resulted in significant mortality of bluebunch wheatgrass, but fall burning did cause significant mortality of Idaho fescue, where 20% of the population was killed. Fall burning stimulated tillering of bluebunch wheatgrass, as the average basal area increased both one and two years following burning. Average basal area per plant of Idaho fescue was reduced by 23% the first year following fall burning; however plants recovered to 90% of their preburn size by the second post-fire year. Spring burning resulted in no significant change in basal area of either species. Fall burning significantly reduced the number of flowering culms on bluebunch wheatgrass plants the first post-fire year (from 36 to 12 per plant); however, by the second post-fire year, number of flowering culms was significantly greater than either pre-burn or control levels (59/plant). Similarly, fall burning of Idaho fescue averaged 60% more flowering culms per plant as adjacent controls (11 compared to 7/plant). Spring burning reduced flowering of both species the first year following burning. Both burn treatments reduced the frequency of annual grasses, while causing no change in frequency of perennial grasses. Annual forbs increased in abundance following both burn treatments. Fire resulted in replacement of exotic annual grasses with annual forb species. Dominant perennial forbs responded variably in both burn treatments, as well as control plots. Frequency of sagebrush increased significantly in both spring and control experimental units in 1989 (one year after spring burning), while fall burns (two years posttreatment) demonstrated no such increase. Apparently, factors relating to the greater fire severity (e.g. consumption, total energy) in the fall burns reduced the rate and degree of reinvasion by sagebrush in the fall burn plots. Densities of annual grasses and woody species were significantly reduced by both burn treatments. Cheatgrass (Bromus tectorum L.) density before burning averaged 446 and 552/m2 in fall and spring units, respectively, as compared to 10 and 85/m2, respectively, the first post-fire year. Big sagebrush was completely eliminated by the fall fire, while spring burning resulted in an 84% decrease in density. Density of western juniper (Juniperus occidentalls Hook.) was reduced 100% by both burn treatments. Species diversity, as measured by the Shannon-Weaver Index (H'), was reduced by fall burning from 2.69 before treatment to 2.53 the first year following burning , but increased to 2.81 second post-fire year. Control plots behaved similarly, although changes were not as great. Changes were most evident in terms of rare species, many of which were not present prior to burning. Spring burning resulted in an no change in species diversity the first year after burning, although, species richness increased from 34 to 41. Both burn treatments appeared effective at changing stand structure to that of a dominance by native perrenial grasses and forbs. The reduced competition from woody plants has, and presumably will continue to favor surviving herbaceous plants. Overall fire effects appear to fit into land management policy of the National Park Service in regard to maintaining wildlands in a pristine state. Specifically, both spring and fall burning reduced fuel hazard, and increased the relative abundance of native species, indicating that prescribed burning may be an effective land management tool for the National Park Service and others managing similar rangelands. Title: Ecological effects of spring and fall prescribed burning on basin big sagebrush : Idaho fescue--bluebunch wheatgrass communities Author: Sapsis, David B. The vegetation response of spring and fall prescribed fires in basin big sagebrush (Artemisia tridentata subsp. tridentata Nutt.)/Idaho fescue (Festuca idahoensis Elmer)--bluebunch wheatgrass (Agropyron spicatum Pursh. (Scribn. & Smith)) communities was measured at the John Day Fossil Beds National Monument in eastern Oregon. Objectives of the study were to quantify fuel loads, environmental conditions, fire behavior and vegetation response corresponding to these two fire treatments. Pretreatment fuel loads in the experimental units ranged from 5 to 12 Mg/ha, with the fall treatment units averaging 10.5 Mg/ha, and the spring units averaging 6.2 Mg/ha. Both treatments contained large amounts (> 3 Mg/ha) of herbaceous fuels. Moisture content of grass and herb fuels were significantly greater in the spring burned units. This is believed to be largely responsible for the less severe fire behavior observed in the spring burn treatment. Flame lengths averaged 4.2 m in fall burns, compared to a mean of 1.7 m in the spring plots. Similarly, rate of spread was significantly greater in the fall units, averaging 1.6 m/s, compared to 0.2 m/s in the spring treatment. Fireline Intensity was seven times greater, and total energy release was twice was great in the fall burns. Neither burn treatment resulted in significant mortality of bluebunch wheatgrass, but fall burning did cause significant mortality of Idaho fescue, where 20% of the population was killed. Fall burning stimulated tillering of bluebunch wheatgrass, as the average basal area increased both one and two years following burning. Average basal area per plant of Idaho fescue was reduced by 23% the first year following fall burning; however plants recovered to 90% of their preburn size by the second post-fire year. Spring burning resulted in no significant change in basal area of either species. Fall burning significantly reduced the number of flowering culms on bluebunch wheatgrass plants the first post-fire year (from 36 to 12 per plant); however, by the second post-fire year, number of flowering culms was significantly greater than either pre-burn or control levels (59/plant). Similarly, fall burning of Idaho fescue averaged 60% more flowering culms per plant as adjacent controls (11 compared to 7/plant). Spring burning reduced flowering of both species the first year following burning. Both burn treatments reduced the frequency of annual grasses, while causing no change in frequency of perennial grasses. Annual forbs increased in abundance following both burn treatments. Fire resulted in replacement of exotic annual grasses with annual forb species. Dominant perennial forbs responded variably in both burn treatments, as well as control plots. Frequency of sagebrush increased significantly in both spring and control experimental units in 1989 (one year after spring burning), while fall burns (two years posttreatment) demonstrated no such increase. Apparently, factors relating to the greater fire severity (e.g. consumption, total energy) in the fall burns reduced the rate and degree of reinvasion by sagebrush in the fall burn plots. Densities of annual grasses and woody species were significantly reduced by both burn treatments. Cheatgrass (Bromus tectorum L.) density before burning averaged 446 and 552/m2 in fall and spring units, respectively, as compared to 10 and 85/m2, respectively, the first post-fire year. Big sagebrush was completely eliminated by the fall fire, while spring burning resulted in an 84% decrease in density. Density of western juniper (Juniperus occidentalls Hook.) was reduced 100% by both burn treatments. Species diversity, as measured by the Shannon-Weaver Index (H'), was reduced by fall burning from 2.69 before treatment to 2.53 the first year following burning , but increased to 2.81 second post-fire year. Control plots behaved similarly, although changes were not as great. Changes were most evident in terms of rare species, many of which were not present prior to burning. Spring burning resulted in an no change in species diversity the first year after burning, although, species richness increased from 34 to 41. Both burn treatments appeared effective at changing stand structure to that of a dominance by native perrenial grasses and forbs. The reduced competition from woody plants has, and presumably will continue to favor surviving herbaceous plants. Overall fire effects appear to fit into land management policy of the National Park Service in regard to maintaining wildlands in a pristine state. Specifically, both spring and fall burning reduced fuel hazard, and increased the relative abundance of native species, indicating that prescribed burning may be an effective land management tool for the National Park Service and others managing similar rangelands. Close

• 58. [Image] Range maps of terrestrial species in the interior Columbia River basin and Northern portions of the Klamath and Great Basins

  	Abstract Marcot, Bruce G.; Wales, Barbara C; Demmer, Rick. 2003. Range maps of terrestrial species in the interior Columbia River basin and northern portions of the Klamath and Great Basins. Gen. Tech. ...
  	Citation × Citation Citation Abstract Copy Title: Range maps of terrestrial species in the interior Columbia River basin and Northern portions of the Klamath and Great Basins Author: Marcot, Bruce G. Year: 2003, 2005, 2004 Abstract Marcot, Bruce G.; Wales, Barbara C; Demmer, Rick. 2003. Range maps of terrestrial species in the interior Columbia River basin and northern portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-583. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 304 p. Current range distribution maps are presented for 14 invertebrate, 26 amphibian, 26 reptile, 339 bird, and 125 mammal species and selected subspecies (530 total taxa) of the interior Columbia River basin and northern portions of the Klamath and Great Basins in the United States. Also presented are maps of historical ranges of 3 bird and 10 mammal species, and 6 maps of natural areas designated by federal agencies and other organizations. The species range maps were derived from a variety of publications and from expert review and unpublished data, and thus differ in degree of accuracy and resolution. The species maps are available in computer versions and are indexed herein by common and scientific names. Keywords: Maps, species range, species distribution, wildlife, invertebrates, arthropods, amphibians, reptiles, birds, mammals, bats, biodiversity, endemism, natural areas, interior Columbia River basin, Klamath Basin, Great Basin. Title: Range maps of terrestrial species in the interior Columbia River basin and Northern portions of the Klamath and Great Basins Author: Marcot, Bruce G. Year: 2003, 2005, 2004 Abstract Marcot, Bruce G.; Wales, Barbara C; Demmer, Rick. 2003. Range maps of terrestrial species in the interior Columbia River basin and northern portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-583. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 304 p. Current range distribution maps are presented for 14 invertebrate, 26 amphibian, 26 reptile, 339 bird, and 125 mammal species and selected subspecies (530 total taxa) of the interior Columbia River basin and northern portions of the Klamath and Great Basins in the United States. Also presented are maps of historical ranges of 3 bird and 10 mammal species, and 6 maps of natural areas designated by federal agencies and other organizations. The species range maps were derived from a variety of publications and from expert review and unpublished data, and thus differ in degree of accuracy and resolution. The species maps are available in computer versions and are indexed herein by common and scientific names. Keywords: Maps, species range, species distribution, wildlife, invertebrates, arthropods, amphibians, reptiles, birds, mammals, bats, biodiversity, endemism, natural areas, interior Columbia River basin, Klamath Basin, Great Basin. Close

• 59. [Image] Macroecology, paleoecology, and ecological integrity of terrestrial species and communities of the interior Columbia River basin and northern portions of the Klamath and Great Basins

  	This report presents information on biogeography and broad-scale ecology (macroecology) of selected fungi, lichens, bryophytes, vascular plants, invertebrates, and vertebrates of the interior Columbia ...
  	Citation × Citation Citation Abstract Copy Title: Macroecology, paleoecology, and ecological integrity of terrestrial species and communities of the interior Columbia River basin and northern portions of the Klamath and Great Basins Author: U.S. Department of Agriculture. Forest Service. Pacific Northwest Research Station; U.S.Department of the Interior. Bureau of Land Management. Year: 1998, 2006, 2005 This report presents information on biogeography and broad-scale ecology (macroecology) of selected fungi, lichens, bryophytes, vascular plants, invertebrates, and vertebrates of the interior Columbia River basin and adjacent areas. Rare plants include many endemics associated with local conditions. Potential plant and invertebrate bioindicators are identified. Species ecological functions differ among communities and variously affect ecosystem diversity and productivity. Species of alpine and subalpine communities are identified that may be at risk from climate change. Maps of terrestrial ecological integrity are presented. Keywords: Macroecology, paleoecology, ecological integrity, terrestrial communities, ecosystems, wildlife, fungi, lichens, bryophytes, vascular plants, invertebrates, arthropods, mollusks, amphibians, reptiles, birds, mammals, endemism, interior Columbia River basin, Klamath Basin, Great Basin. Title: Macroecology, paleoecology, and ecological integrity of terrestrial species and communities of the interior Columbia River basin and northern portions of the Klamath and Great Basins Author: U.S. Department of Agriculture. Forest Service. Pacific Northwest Research Station; U.S.Department of the Interior. Bureau of Land Management. Year: 1998, 2006, 2005 This report presents information on biogeography and broad-scale ecology (macroecology) of selected fungi, lichens, bryophytes, vascular plants, invertebrates, and vertebrates of the interior Columbia River basin and adjacent areas. Rare plants include many endemics associated with local conditions. Potential plant and invertebrate bioindicators are identified. Species ecological functions differ among communities and variously affect ecosystem diversity and productivity. Species of alpine and subalpine communities are identified that may be at risk from climate change. Maps of terrestrial ecological integrity are presented. Keywords: Macroecology, paleoecology, ecological integrity, terrestrial communities, ecosystems, wildlife, fungi, lichens, bryophytes, vascular plants, invertebrates, arthropods, mollusks, amphibians, reptiles, birds, mammals, endemism, interior Columbia River basin, Klamath Basin, Great Basin. Close

• 60. [Image] Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States

  	Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references
  	Citation × Citation Citation Abstract Copy Title: Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States Author: Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western U.S. (3rd : 1994 : Watsonville, Calif.) Year: 1996, 2007, 2005 Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references Title: Report of 1994 Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western United States Author: Workshop on the Correlation of Marine and Terrestrial Records of Climate Changes in the Western U.S. (3rd : 1994 : Watsonville, Calif.) Year: 1996, 2007, 2005 Imprint from transmittal sheet; Distributed to depository libraries in microfiche; Shipping list no.: 97-0071-M; One ill. on 1 folded leaf in pocket; Includes bibliographical references Close