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• 1. [Article] Causes and Consequences of Mitochondrial Variation in Caenorhabditid Nematodes

  Mitochondria are dynamic organelles that harbor their own stream-lined genome and generate much of the ATP necessary to sustain eukaryotic life via an electron transport chain (ETC). Because of the central ...

  Citation × Citation Citation Abstract Copy Title: Causes and Consequences of Mitochondrial Variation in Caenorhabditid Nematodes Author: Hicks, Kiley Ann Year: 2012 Mitochondria are dynamic organelles that harbor their own stream-lined genome and generate much of the ATP necessary to sustain eukaryotic life via an electron transport chain (ETC). Because of the central role for mitochondria in organismal physiology, mitochondrial genetic and phenotypic variation can alter organismal fitness and affect population genetic and evolutionary outcomes. Despite the far-reaching relevance of mitochondria to evolutionary processes and human health, we lack a basic understanding of the causes and consequences of mitochondrial genetic and phenotypic variation. In this thesis, I quantified mitochondrial reactive oxygen species (ROS), membrane potential (δΨM), and mitochondrial morphological traits within Caenorhabditis briggsae natural isolates and mutation-accumulation (MA) lines of both C. briggsae and Caenorhabditis elegans. Substantial natural variation was discovered for most mitochondrial form and function traits measured for a set of C. briggsae isolates known to harbor mitochondrial DNA structural variation in the form of a heteroplasmic nad5 gene deletion (nad5δ) that correlates negatively with organismal fitness. Most among-isolate phenotypic variation could be accounted for by phylogeographic clade membership rather than nad5δ level. Analysis of mitochondrial-nuclear hybrid strains provided support for both mtDNA and nuclear genetic variation as drivers of natural mitochondrial phenotype variation. An MA experimental approach revealed that average levels of both ROS and nad5δ heteroplasmy evolved in remarkably linear ways in C. briggsae maintained under extreme inbreeding. In particular, among C. briggsae isolates prone to acquiring the nad5δ deletion, nad5δ level increased to a plateau of ~50% during successive generations of MA treatment. Conversely, mitochondrial ROS level increased or declined in a strain-specific fashion, which also meant that the relationship between ROS and nad5δ was strain-specific. Further, all lines generated from the isolate with the highest starting level of nad5δ heteroplasmy went extinct prior to generation 20 of MA treatment. Patterns of among-line variance in ROS level were also strain-specific but generally did not conform to the canonical pattern of increasing among-line variance expected for MA experiments. MA lines of C. elegans that had previously been subjected to whole-genome sequencing were found to vary significantly in ROS levels but not in 8-oxo-dG content. Despite a significant positive correlation between 8-oxo-dG and ROS levels, no relationship between oxidative stress measures and base substitution rate or G-to-T transversion rate was revealed. Finally, analysis of patterns of phenotypic correlation for a suite of 24 mitochondrial traits measured in C. briggsae natural isolates support a role for ΔΨM in shaping mitochondrial dynamics, but no such role for mitochondrial ROS. Further, our study suggests a novel model of mitochondrial population dynamics dependent upon cellular environmental context and with implications for mitochondrial genome integrity. This work identifies extensive natural variation and capacity for evolution in organellar traits within multicellular eukaryotic species, with a central role for δΨM in mitochondrial dynamics that may have implications for evolutionary adaptation to thermal niches. Title: Causes and Consequences of Mitochondrial Variation in Caenorhabditid Nematodes Author: Hicks, Kiley Ann Year: 2012 Mitochondria are dynamic organelles that harbor their own stream-lined genome and generate much of the ATP necessary to sustain eukaryotic life via an electron transport chain (ETC). Because of the central role for mitochondria in organismal physiology, mitochondrial genetic and phenotypic variation can alter organismal fitness and affect population genetic and evolutionary outcomes. Despite the far-reaching relevance of mitochondria to evolutionary processes and human health, we lack a basic understanding of the causes and consequences of mitochondrial genetic and phenotypic variation. In this thesis, I quantified mitochondrial reactive oxygen species (ROS), membrane potential (δΨM), and mitochondrial morphological traits within Caenorhabditis briggsae natural isolates and mutation-accumulation (MA) lines of both C. briggsae and Caenorhabditis elegans. Substantial natural variation was discovered for most mitochondrial form and function traits measured for a set of C. briggsae isolates known to harbor mitochondrial DNA structural variation in the form of a heteroplasmic nad5 gene deletion (nad5δ) that correlates negatively with organismal fitness. Most among-isolate phenotypic variation could be accounted for by phylogeographic clade membership rather than nad5δ level. Analysis of mitochondrial-nuclear hybrid strains provided support for both mtDNA and nuclear genetic variation as drivers of natural mitochondrial phenotype variation. An MA experimental approach revealed that average levels of both ROS and nad5δ heteroplasmy evolved in remarkably linear ways in C. briggsae maintained under extreme inbreeding. In particular, among C. briggsae isolates prone to acquiring the nad5δ deletion, nad5δ level increased to a plateau of ~50% during successive generations of MA treatment. Conversely, mitochondrial ROS level increased or declined in a strain-specific fashion, which also meant that the relationship between ROS and nad5δ was strain-specific. Further, all lines generated from the isolate with the highest starting level of nad5δ heteroplasmy went extinct prior to generation 20 of MA treatment. Patterns of among-line variance in ROS level were also strain-specific but generally did not conform to the canonical pattern of increasing among-line variance expected for MA experiments. MA lines of C. elegans that had previously been subjected to whole-genome sequencing were found to vary significantly in ROS levels but not in 8-oxo-dG content. Despite a significant positive correlation between 8-oxo-dG and ROS levels, no relationship between oxidative stress measures and base substitution rate or G-to-T transversion rate was revealed. Finally, analysis of patterns of phenotypic correlation for a suite of 24 mitochondrial traits measured in C. briggsae natural isolates support a role for ΔΨM in shaping mitochondrial dynamics, but no such role for mitochondrial ROS. Further, our study suggests a novel model of mitochondrial population dynamics dependent upon cellular environmental context and with implications for mitochondrial genome integrity. This work identifies extensive natural variation and capacity for evolution in organellar traits within multicellular eukaryotic species, with a central role for δΨM in mitochondrial dynamics that may have implications for evolutionary adaptation to thermal niches. Close

• 2. [Article] Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon

  The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed ...

  Citation × Citation Citation Abstract Copy Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Title: Studies of ecological factors that affect the population and distribution of the western gray squirrel in northcentral Oregon Author: Foster, Susan Ann Year: 1992 The western gray squirrel (Sciurus griseus griseus Ord) occur only in the Pacific states and in a small corner of extreme western Nevada. Field studies of aspects of the ecology of the most widely distributed subspecies of western gray squirrel (S. griseus) were conducted at three sites in the ponderosa pine-Oregon white oak zone on the eastern slopes of Mt. Hood, Wasco County, Oregon, between 1981 and 1989. From 1981 through 1987, a Hunter Cooperation Program provided remains of squirrels shot during the annual late summer-early autumn hunting season. Other data were gathered through capture and release studies, radiotelemetry, and habitat analysis. The age structure of these populations, as revealed by examination of squirrels killed by hunters, is predominantly mature animals. Also, the population as estimated by hunter success during the Hunter Cooperation Program and by field observations appears to be declining. In the sites studied, western gray squirrels have two seasons of reproductive activity annually. Some individuals mate from January through March; their young emerge from the nest in May and June. Other individuals mate during May and June; their young emerge in August and September. The latter matings are usually the most productive. Analysis of nest trees and their surroundings revealed that nests are most likely to be located in mature trees that have well-developed crowns and occur in stands with a high degree of canopy closure. Nest trees were usually located within approximately 180 meters of permanent water and on sites with a south-southeasterly exposure. Home ranges of squirrels examined in this study were usually large compared to home ranges reported for this species elsewhere in its range. Given the cost of having large home ranges, it seems possible that the squirrels at these study sites exist in less than optimal ecological circumstances. Human factors that may have contributed to the decline of the populations in this study may include the nature of logging activities and the timing of the annual hunting season. Limiting factors other than human activities may include competition with other mast-consuming animals (mule deer, elk, wild turkeys, and three other species of squirrels) for limited and variable mast crops. Close

• 3. [Article] The Biology of Eastern Kingbirds at Malheur National Wildlife Refuge: Survival, Reproduction, and Testosterone Secretion

  This dissertation presents the results of a study that I undertook to better understand the breeding biology of Eastern Kingbirds (hereafter, kingbirds) at Malheur National Wildlife Refuge in southeastern ...

  Citation × Citation Citation Abstract Copy Title: The Biology of Eastern Kingbirds at Malheur National Wildlife Refuge: Survival, Reproduction, and Testosterone Secretion Author: Redmond, Lucas J. Year: 2015 This dissertation presents the results of a study that I undertook to better understand the breeding biology of Eastern Kingbirds (hereafter, kingbirds) at Malheur National Wildlife Refuge in southeastern Oregon from 2003 to 2009. Kingbirds are long-distance migratory songbirds that breed across much of North America. This species is socially monogamous but, via frequent extra-pair copulations, is genetically polygamous. Kingbirds exhibit relatively high breeding site fidelity, often returning to the same tree to nest in subsequent years. Both members of a pair provide parental care, but there are often specific duties performed by both male and female kingbirds. For example, males typically perform much of the vigilant nest defense that this species is well known for and contribute, to an extent, to the feeding of nestlings. Females, on the other hand, are entirely responsible for incubating and brooding. Beginning in 2002, most adults within the population of kingbirds at Malheur had been banded with a unique combination of three colored plastic leg bands and an aluminum USFWS band. Also, as many nests were located in each year as possible, and any young that survived to fledging age were banded with a unique combination of leg bands. Considerable effort was then spent each year to locate as many banded individuals as possible, which allowed me to document adult and juvenile survival. Annual survival rates of adult male and female kingbirds in the population at Malheur did not differ and were relatively high at approximately 0.65. Juvenile survival rate was approximately 0.29, indicating that slightly less than one-third of nestlings survive the interval between fledging and their first potential breeding season. Resighting probability was high for both sexes, although higher for adult males (0.94) than for adult female (0.84). The latter finding is consistent with the higher site fidelity of males than of females. Resighting probabilities for juveniles were much lower at 0.68 and 0.40 for males and females, respectively. Again, this was expected because natal site fidelity is typically much lower than breeding site fidelity. Compared to most other reports, resighting probability and return rates of juvenile kingbirds was high, presumably because the riparian habitats where kingbirds breed at Malheur function as an ecological island surrounded by, for kingbirds, unsuitable high desert habitat. Thus, unless they disperse very long distances, the only option for juvenile kingbirds is to begin nesting on the refuge. The collection of blood samples from birds has become an increasingly common practice in ornithology. The data that can be gained from these samples allow a number of interesting questions to be asked such as understanding the genetic mating system of a species, patterns of hormone secretion, and discerning migratory pathways via stable isotope analysis. The volume of blood collected is usually small and was assumed to cause no long-term negative effects on sampled individuals. However, few studies have rigorously examined the effect of blood sampling on survival. I used a multistate mark-recapture analysis to assess the effect blood sampling on annual survival of kingbirds by combining the annual survival data described above with whether or not individuals were subjected to blood sample collection. The results of this analysis indicated that blood sampling had no effect on annual survival rates of kingbirds. Whether or not this is the case for other species remains to be seen. However, my results support the assumption that when done correctly, blood sampling has little to no long-term negative effects on birds. Comparative analyses of many bird species show that testosterone secretion exhibits fairly predictable patterns among breeding birds of different mating systems. Monogamous species reach a peak during mate attraction and the period of female fertility which is then followed by a sharp decline when young are in the nest. By contrast, males of polygynous species tend to maintain higher levels of testosterone throughout the breeding season to, presumably, maximize opportunities for acquiring additional mates. Kingbirds are socially monogamous but cryptically polygamous. However, because of high rates of extra-pair paternity, variation in reproductive success among males is much higher than what is expected for a monogamous species, and, instead, is similar to what has been reported for polygynous species. Therefore from 2005 to 2009 I measured testosterone concentrations from the blood samples collected from male kingbirds to determine the breeding season profile of testosterone secretion in kingbirds and to understand the factors that influence testosterone variation among individuals. Contrary to expected for a monogamous species, the testosterone profile of kingbirds did not exhibit the brief peak in testosterone followed by a precipitous decline. Testosterone peaked early in the season, but declined very slowly as the nest cycle progressed. I attributed this gradual decline in testosterone to the cryptically polygynous nature of the kingbird extra-pair mating system. I also found substantial variation in testosterone concentration among male kingbirds and was able to identify several factors contributing to this variation. As expected, testosterone declined as the breeding season progressed (independent of stage in nest cycle) and nest density increased, while increases in testosterone were correlated with the number of fertile females within the population. This suggests that male kingbirds were capable of modulating testosterone concentrations to both cope with an increase in conspecific density, but also to ready themselves for times when extra-pair copulations were more likely. Title: The Biology of Eastern Kingbirds at Malheur National Wildlife Refuge: Survival, Reproduction, and Testosterone Secretion Author: Redmond, Lucas J. Year: 2015 This dissertation presents the results of a study that I undertook to better understand the breeding biology of Eastern Kingbirds (hereafter, kingbirds) at Malheur National Wildlife Refuge in southeastern Oregon from 2003 to 2009. Kingbirds are long-distance migratory songbirds that breed across much of North America. This species is socially monogamous but, via frequent extra-pair copulations, is genetically polygamous. Kingbirds exhibit relatively high breeding site fidelity, often returning to the same tree to nest in subsequent years. Both members of a pair provide parental care, but there are often specific duties performed by both male and female kingbirds. For example, males typically perform much of the vigilant nest defense that this species is well known for and contribute, to an extent, to the feeding of nestlings. Females, on the other hand, are entirely responsible for incubating and brooding. Beginning in 2002, most adults within the population of kingbirds at Malheur had been banded with a unique combination of three colored plastic leg bands and an aluminum USFWS band. Also, as many nests were located in each year as possible, and any young that survived to fledging age were banded with a unique combination of leg bands. Considerable effort was then spent each year to locate as many banded individuals as possible, which allowed me to document adult and juvenile survival. Annual survival rates of adult male and female kingbirds in the population at Malheur did not differ and were relatively high at approximately 0.65. Juvenile survival rate was approximately 0.29, indicating that slightly less than one-third of nestlings survive the interval between fledging and their first potential breeding season. Resighting probability was high for both sexes, although higher for adult males (0.94) than for adult female (0.84). The latter finding is consistent with the higher site fidelity of males than of females. Resighting probabilities for juveniles were much lower at 0.68 and 0.40 for males and females, respectively. Again, this was expected because natal site fidelity is typically much lower than breeding site fidelity. Compared to most other reports, resighting probability and return rates of juvenile kingbirds was high, presumably because the riparian habitats where kingbirds breed at Malheur function as an ecological island surrounded by, for kingbirds, unsuitable high desert habitat. Thus, unless they disperse very long distances, the only option for juvenile kingbirds is to begin nesting on the refuge. The collection of blood samples from birds has become an increasingly common practice in ornithology. The data that can be gained from these samples allow a number of interesting questions to be asked such as understanding the genetic mating system of a species, patterns of hormone secretion, and discerning migratory pathways via stable isotope analysis. The volume of blood collected is usually small and was assumed to cause no long-term negative effects on sampled individuals. However, few studies have rigorously examined the effect of blood sampling on survival. I used a multistate mark-recapture analysis to assess the effect blood sampling on annual survival of kingbirds by combining the annual survival data described above with whether or not individuals were subjected to blood sample collection. The results of this analysis indicated that blood sampling had no effect on annual survival rates of kingbirds. Whether or not this is the case for other species remains to be seen. However, my results support the assumption that when done correctly, blood sampling has little to no long-term negative effects on birds. Comparative analyses of many bird species show that testosterone secretion exhibits fairly predictable patterns among breeding birds of different mating systems. Monogamous species reach a peak during mate attraction and the period of female fertility which is then followed by a sharp decline when young are in the nest. By contrast, males of polygynous species tend to maintain higher levels of testosterone throughout the breeding season to, presumably, maximize opportunities for acquiring additional mates. Kingbirds are socially monogamous but cryptically polygamous. However, because of high rates of extra-pair paternity, variation in reproductive success among males is much higher than what is expected for a monogamous species, and, instead, is similar to what has been reported for polygynous species. Therefore from 2005 to 2009 I measured testosterone concentrations from the blood samples collected from male kingbirds to determine the breeding season profile of testosterone secretion in kingbirds and to understand the factors that influence testosterone variation among individuals. Contrary to expected for a monogamous species, the testosterone profile of kingbirds did not exhibit the brief peak in testosterone followed by a precipitous decline. Testosterone peaked early in the season, but declined very slowly as the nest cycle progressed. I attributed this gradual decline in testosterone to the cryptically polygynous nature of the kingbird extra-pair mating system. I also found substantial variation in testosterone concentration among male kingbirds and was able to identify several factors contributing to this variation. As expected, testosterone declined as the breeding season progressed (independent of stage in nest cycle) and nest density increased, while increases in testosterone were correlated with the number of fertile females within the population. This suggests that male kingbirds were capable of modulating testosterone concentrations to both cope with an increase in conspecific density, but also to ready themselves for times when extra-pair copulations were more likely. Close

• 4. [Article] Aspects of the physiology and diseases of the North American elk

  Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some ...

  Citation × Citation Citation Abstract Copy Title: Aspects of the physiology and diseases of the North American elk Author: Weber, Yvonne Bernard Year: 1973 Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk. Title: Aspects of the physiology and diseases of the North American elk Author: Weber, Yvonne Bernard Year: 1973 Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk. Close

• 5. [Article] Comparing Twenty-Four Years of Forest Change in Two Communities of Mexico's Meseta Purépecha Using Multi-Spectral Satellite Imagery

  The Meseta Purepecha, a volcanic plateau in the Mexican state of Michoacan, is home to one of the most species-rich pine forests in the world. Recent increases in demand for forest products has put added ...

  Citation × Citation Citation Abstract Copy Title: Comparing Twenty-Four Years of Forest Change in Two Communities of Mexico's Meseta Purépecha Using Multi-Spectral Satellite Imagery Author: Martin, Kevin Scott Year: 2004 The Meseta Purepecha, a volcanic plateau in the Mexican state of Michoacan, is home to one of the most species-rich pine forests in the world. Recent increases in demand for forest products has put added pressure on these resources. Though existing research has suggested significant deforestation in the Meseta, there is little information identifying specific areas of decline. This study focuses on two indigenous communities in the Meseta-Pichataro and Sevina. Both communities have long relied on wood as an economic resource. However, the two communities have reacted differently to increased demand for forest resources. The purpose of this study is to identify the differences in the rate and extent of forest change between Pichataro and Sevina. Three dates of Landsat satellite images - 1976, 1986, and 2000-were used to identify changes in the Meseta's forests. Supervised classification was used to classify the 2000 image into forested and non-forested areas. Change detection was performed on the 1976 through 2000 images to identify areas of forest clearing and forest regrowth. The 2000 image was then used as a reference for generating maps of historic forest extent based on the change detection results. Results show that between 1986 and 2000, Sevina cleared approximately 16% of its forested land between while Pichataro experienced a net gain of 7%. In the same period, 93% of the deforestation in the combined study area occurred within the community boundary of Sevina, which manages only 35% of the study area forests. Sevina's remaining forests are also more isolated and fragmented than the forests of Pichataro. The differences between the two communities appear related to management practices. Sevina has relied on larger-scale timber harvesting to derive economic benefits from its forests. Pichataro has focused on local harvesting and value-added production. Title: Comparing Twenty-Four Years of Forest Change in Two Communities of Mexico's Meseta Purépecha Using Multi-Spectral Satellite Imagery Author: Martin, Kevin Scott Year: 2004 The Meseta Purepecha, a volcanic plateau in the Mexican state of Michoacan, is home to one of the most species-rich pine forests in the world. Recent increases in demand for forest products has put added pressure on these resources. Though existing research has suggested significant deforestation in the Meseta, there is little information identifying specific areas of decline. This study focuses on two indigenous communities in the Meseta-Pichataro and Sevina. Both communities have long relied on wood as an economic resource. However, the two communities have reacted differently to increased demand for forest resources. The purpose of this study is to identify the differences in the rate and extent of forest change between Pichataro and Sevina. Three dates of Landsat satellite images - 1976, 1986, and 2000-were used to identify changes in the Meseta's forests. Supervised classification was used to classify the 2000 image into forested and non-forested areas. Change detection was performed on the 1976 through 2000 images to identify areas of forest clearing and forest regrowth. The 2000 image was then used as a reference for generating maps of historic forest extent based on the change detection results. Results show that between 1986 and 2000, Sevina cleared approximately 16% of its forested land between while Pichataro experienced a net gain of 7%. In the same period, 93% of the deforestation in the combined study area occurred within the community boundary of Sevina, which manages only 35% of the study area forests. Sevina's remaining forests are also more isolated and fragmented than the forests of Pichataro. The differences between the two communities appear related to management practices. Sevina has relied on larger-scale timber harvesting to derive economic benefits from its forests. Pichataro has focused on local harvesting and value-added production. Close

• 6. [Article] Measuring and Managing Resistance and Resilience Under Climate Change in Northern Great Lake Forests (USA)

  Context: Climate change will have diverse and interacting effects on forests over the next century. One of the most pronounced effects may be a decline in resistance to chronic change and resilience to ...

  Citation × Citation Citation Abstract Copy Title: Measuring and Managing Resistance and Resilience Under Climate Change in Northern Great Lake Forests (USA) Author: Duveneck, Matthew Joshua, Scheller, Robert M. Year: 2016 Context: Climate change will have diverse and interacting effects on forests over the next century. One of the most pronounced effects may be a decline in resistance to chronic change and resilience to acute disturbances. The capacity for forests to persist and/or adapt to climate change remains largely unknown, in part because there is not broad agreement how to measure and apply resilience concepts. Objectives: We assessed the interactions of climate change, resistance, resilience, diversity, and alternative management of northern Great Lake forests. Methods: We simulated two landscapes (northern Minnesota and northern lower Michigan), three climate futures (current climate, a low emissions trajectory, and a high emissions trajectory), and four management regimes [business as usual, expanded forest reserves, modified silviculture, and climate suitable planting (CSP)]. We simulated each scenario with a forest landscape simulation model. We assessed resistance as the change in species composition over time. We assessed resilience and calculated an index of resilience that incorporated both recovery of pre-fire tree species composition and aboveground biomass within simulated burned areas. Results: Results indicate a positive relationship between diversity and resistance within low diversity areas. Simulations of the high emission climate future resulted in a decline in both resistance and resilience. Conclusions: Of the management regimes, the CSP regime resulted in some of the greatest resilience under climate change although our results suggest that differences in forest management are largely outweighed by the effects of climate change. Our results provide a framework for assessing resistance and resilience relevant and valuable to a broad array of ecological systems. Title: Measuring and Managing Resistance and Resilience Under Climate Change in Northern Great Lake Forests (USA) Author: Duveneck, Matthew Joshua, Scheller, Robert M. Year: 2016 Context: Climate change will have diverse and interacting effects on forests over the next century. One of the most pronounced effects may be a decline in resistance to chronic change and resilience to acute disturbances. The capacity for forests to persist and/or adapt to climate change remains largely unknown, in part because there is not broad agreement how to measure and apply resilience concepts. Objectives: We assessed the interactions of climate change, resistance, resilience, diversity, and alternative management of northern Great Lake forests. Methods: We simulated two landscapes (northern Minnesota and northern lower Michigan), three climate futures (current climate, a low emissions trajectory, and a high emissions trajectory), and four management regimes [business as usual, expanded forest reserves, modified silviculture, and climate suitable planting (CSP)]. We simulated each scenario with a forest landscape simulation model. We assessed resistance as the change in species composition over time. We assessed resilience and calculated an index of resilience that incorporated both recovery of pre-fire tree species composition and aboveground biomass within simulated burned areas. Results: Results indicate a positive relationship between diversity and resistance within low diversity areas. Simulations of the high emission climate future resulted in a decline in both resistance and resilience. Conclusions: Of the management regimes, the CSP regime resulted in some of the greatest resilience under climate change although our results suggest that differences in forest management are largely outweighed by the effects of climate change. Our results provide a framework for assessing resistance and resilience relevant and valuable to a broad array of ecological systems. Close

• 7. [Article] Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries

  The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, ...

  Citation × Citation Citation Abstract Copy Title: Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries Author: Yildirimer, Christina Carrell Year: 2017 The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess microbial community diversity. The Cascade Mountains serve as an allopatric border between two distinct clades of steelhead that show significant differences in genomic and mitochondrial diversity. We identified differences in core microbiota of hatchery-reared fish that correlate with this divergent phylogeographic distribution. Steelhead sampled from hatcheries east of the Cascades had overall greater core gut microbiota diversity. These differences were found despite similarities in diet and rearing conditions. In addition to taxonomic variation across the geographic divide, we identified significant differences in metabolic pathways using PICRUSt gene prediction software. Our analysis revealed significant enrichment of genes associated with lipid metabolism in the gut microbiome of western fish. 8 of 19 individual lipid metabolism pathways were more prominent in western populations. Lipids are a vital nutritional component for teleost species involved in migration and subsequent return for spawning in natal environments. We hypothesize that the observed differences in lipid metabolism across this phylogenetic divide results from an increased ability of eastern Cascade (O. m. gairdneri) fish to utilize lipids taken in via the diet. This increased absorption and utilization would make lipids less available for the intestinal microbiota of the eastern fish, as evidenced by the lower abundance of lipid metabolism genes in the east. Our research utilizes information from the microbiome to understand the phenotypic implications occurring in segregated populations of hatchery-reared steelhead, further confirming elements of coevolution between an organism and its internal environment. Title: Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries Author: Yildirimer, Christina Carrell Year: 2017 The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess microbial community diversity. The Cascade Mountains serve as an allopatric border between two distinct clades of steelhead that show significant differences in genomic and mitochondrial diversity. We identified differences in core microbiota of hatchery-reared fish that correlate with this divergent phylogeographic distribution. Steelhead sampled from hatcheries east of the Cascades had overall greater core gut microbiota diversity. These differences were found despite similarities in diet and rearing conditions. In addition to taxonomic variation across the geographic divide, we identified significant differences in metabolic pathways using PICRUSt gene prediction software. Our analysis revealed significant enrichment of genes associated with lipid metabolism in the gut microbiome of western fish. 8 of 19 individual lipid metabolism pathways were more prominent in western populations. Lipids are a vital nutritional component for teleost species involved in migration and subsequent return for spawning in natal environments. We hypothesize that the observed differences in lipid metabolism across this phylogenetic divide results from an increased ability of eastern Cascade (O. m. gairdneri) fish to utilize lipids taken in via the diet. This increased absorption and utilization would make lipids less available for the intestinal microbiota of the eastern fish, as evidenced by the lower abundance of lipid metabolism genes in the east. Our research utilizes information from the microbiome to understand the phenotypic implications occurring in segregated populations of hatchery-reared steelhead, further confirming elements of coevolution between an organism and its internal environment. Close

• 8. [Article] “A Caretaker Responsibility”: Revisiting Klamath and Modoc Traditions of Plant Community Management

  Conventionally, the Klamath and Modoc Indians of south-central Oregon and northeastern California are depicted as hunter-gatherers, who took no active role in the management of plant communities. In the ...

  Citation × Citation Citation Abstract Copy Title: “A Caretaker Responsibility”: Revisiting Klamath and Modoc Traditions of Plant Community Management Author: Deur, Douglas Year: 2009 Conventionally, the Klamath and Modoc Indians of south-central Oregon and northeastern California are depicted as hunter-gatherers, who took no active role in the management of plant communities. In the course of a multi-year ethnographic effort, however, tribal elders have identified a complex of interrelated plant management practices that are consistent with contemporary definitions of plant cultivation. These include the management of black huckleberry (Vaccinium membranaceum) yields in subalpine environments, the management of marsh-edge environments for yellow pond lily (Nuphar polysepalum), the tending of ‘‘epos’’ or yampah (Perideridia spp.) digging sites, and the selective harvest of tree cambium, sap, and wood – especially from pines (Pinus spp.) and junipers (Juniperus spp). Together, these accounts suggest that plant management was widespread, that it often served to geographically concentrate culturally preferred species, and that it was rooted as much in cosmological motivations as economic ones. Factors contributing to the decline of traditional management practices are also briefly addressed. Title: “A Caretaker Responsibility”: Revisiting Klamath and Modoc Traditions of Plant Community Management Author: Deur, Douglas Year: 2009 Conventionally, the Klamath and Modoc Indians of south-central Oregon and northeastern California are depicted as hunter-gatherers, who took no active role in the management of plant communities. In the course of a multi-year ethnographic effort, however, tribal elders have identified a complex of interrelated plant management practices that are consistent with contemporary definitions of plant cultivation. These include the management of black huckleberry (Vaccinium membranaceum) yields in subalpine environments, the management of marsh-edge environments for yellow pond lily (Nuphar polysepalum), the tending of ‘‘epos’’ or yampah (Perideridia spp.) digging sites, and the selective harvest of tree cambium, sap, and wood – especially from pines (Pinus spp.) and junipers (Juniperus spp). Together, these accounts suggest that plant management was widespread, that it often served to geographically concentrate culturally preferred species, and that it was rooted as much in cosmological motivations as economic ones. Factors contributing to the decline of traditional management practices are also briefly addressed. Close

• 9. [Article] Avian population trends within the evolving agricultural landscape of the eastern and central United States

  State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have ...

  Citation × Citation Citation Abstract Copy Title: Avian population trends within the evolving agricultural landscape of the eastern and central United States Author: Murphy, Michael T. Year: 2003 State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant association between population trends and changes in agricultural land use, and in most, land use "explained" 25-30% of the variation in population trends among states. Changes in the farmland landscape accounted for more of the interstate variability of population trends of short-distance migrants than of both long-distance migrants and residents, and that variability was greater in grassland than shrub species. Declines in the area of rangeland and cover crops were followed by population declines and increases, respectively, by many species. Increases of land in the Conservation Reserve Program had negative associations with population trends of some shrub species. The results indicate that grassland birds have declined strongly over the past two decades, and that regardless of migratory behavior or nesting habits, avian population trends are linked strongly to changes in agricultural land use within North America. Title: Avian population trends within the evolving agricultural landscape of the eastern and central United States Author: Murphy, Michael T. Year: 2003 State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant association between population trends and changes in agricultural land use, and in most, land use "explained" 25-30% of the variation in population trends among states. Changes in the farmland landscape accounted for more of the interstate variability of population trends of short-distance migrants than of both long-distance migrants and residents, and that variability was greater in grassland than shrub species. Declines in the area of rangeland and cover crops were followed by population declines and increases, respectively, by many species. Increases of land in the Conservation Reserve Program had negative associations with population trends of some shrub species. The results indicate that grassland birds have declined strongly over the past two decades, and that regardless of migratory behavior or nesting habits, avian population trends are linked strongly to changes in agricultural land use within North America. Close

• 10. [Article] The Impact of Weather on Kingbird Foraging Behavior

  Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior ...

  Citation × Citation Citation Abstract Copy Title: The Impact of Weather on Kingbird Foraging Behavior Author: Murphy, Michael T. Year: 1987 Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's (1980) generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total foraging rate was independent of air temperature, cloud cover, wind speed, and time of day, but the rate of aerial hawking varied directly with air temperature and inversely with cloud cover (both P < 0.05). Effects of the two variables were additive. The percentage of foraging movements that were aerial hawks also increased with temperature and declined with cloud cover, and, hover-gleaning and perch-to-ground sallying were observed mainly during cloudy weather. Sally (i.e., foraging flight) distance correlated directly with perch height and air temperature, and large insects were captured almost exclusively in long upward or horizontal flights. I interpret these data to indicate that foraging behavior and the capture of large, flying insects depends on weather because of how it affects the activity of insect prey. Foraging data on kingbirds support Fitzpatrick's generalization, but the relative use of aerial hawking varies considerably among species. Resident Tropical Kingbirds( T. melancholicus) are the most specialized foragers, whereas the migrant and widely distributed Eastern Kingbird appears to be the most generalized. Certain habitats also appear to favor the use of particular foraging methods (e.g., outward striking in grasslands and perch-to-ground sallying in drier, open habitats). Title: The Impact of Weather on Kingbird Foraging Behavior Author: Murphy, Michael T. Year: 1987 Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's (1980) generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total foraging rate was independent of air temperature, cloud cover, wind speed, and time of day, but the rate of aerial hawking varied directly with air temperature and inversely with cloud cover (both P < 0.05). Effects of the two variables were additive. The percentage of foraging movements that were aerial hawks also increased with temperature and declined with cloud cover, and, hover-gleaning and perch-to-ground sallying were observed mainly during cloudy weather. Sally (i.e., foraging flight) distance correlated directly with perch height and air temperature, and large insects were captured almost exclusively in long upward or horizontal flights. I interpret these data to indicate that foraging behavior and the capture of large, flying insects depends on weather because of how it affects the activity of insect prey. Foraging data on kingbirds support Fitzpatrick's generalization, but the relative use of aerial hawking varies considerably among species. Resident Tropical Kingbirds( T. melancholicus) are the most specialized foragers, whereas the migrant and widely distributed Eastern Kingbird appears to be the most generalized. Certain habitats also appear to favor the use of particular foraging methods (e.g., outward striking in grasslands and perch-to-ground sallying in drier, open habitats). Close