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• 1. [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

• 2. [Article] Small Tidal Channels Improve Foraging Opportunities for Calidris Shorebirds

  Estuarine intertidal habitats are heterogeneous, therefore migratory shorebirds are expected to forage in microhabitats where they can maximize their energy intake. Identifying proximate factors that migratory ...

  Citation × Citation Citation Abstract Copy Title: Small Tidal Channels Improve Foraging Opportunities for Calidris Shorebirds Author: Miller, Aileen K., de Rivera, Catherine E. Year: 2014 Estuarine intertidal habitats are heterogeneous, therefore migratory shorebirds are expected to forage in microhabitats where they can maximize their energy intake. Identifying proximate factors that migratory shorebirds use to accept or reject a particular habitat patch will help land managers make conservation and restoration decisions that provide the greatest benefits to shorebird populations during migration, a period of intense energy usage. We examined whether small semipermanent tidal channels were preferentially used by foraging Western Sandpipers (Calidris mauri) and Dunlins (C. alpina) during a spring migratory stopover in Bandon Marsh, an Oregon, USA, estuary. Further, we tested alternative hypotheses about how channels might be beneficial to shorebirds by examining infauna abundance, composition, and depth alongside channels compared with that in open mudflats. The densities of Western Sandpipers and Dunlins were at least 4 times higher along channels than in open mudflat habitats. Infauna along channels were twice as abundant as those in the surrounding mudflats, and infauna were generally found closer to the surface. Furthermore, sediment alongside channels required less than half the force to probe, probably increasing shorebirds' overall access to prey. We conclude that shorebirds selected microhabitats near channels because of the greater food abundance and availability. Additional evidence suggested that another microhabitat, patches of red algae (Gracilaria sp.), may also have conferred advantages on foraging shorebirds. Channels may be a valuable microhabitat to consider when selecting conservation areas for shorebirds, and maintaining channels (e.g., through maintaining natural hydrology and sedimentation patterns) should be considered in management practices. Title: Small Tidal Channels Improve Foraging Opportunities for Calidris Shorebirds Author: Miller, Aileen K., de Rivera, Catherine E. Year: 2014 Estuarine intertidal habitats are heterogeneous, therefore migratory shorebirds are expected to forage in microhabitats where they can maximize their energy intake. Identifying proximate factors that migratory shorebirds use to accept or reject a particular habitat patch will help land managers make conservation and restoration decisions that provide the greatest benefits to shorebird populations during migration, a period of intense energy usage. We examined whether small semipermanent tidal channels were preferentially used by foraging Western Sandpipers (Calidris mauri) and Dunlins (C. alpina) during a spring migratory stopover in Bandon Marsh, an Oregon, USA, estuary. Further, we tested alternative hypotheses about how channels might be beneficial to shorebirds by examining infauna abundance, composition, and depth alongside channels compared with that in open mudflats. The densities of Western Sandpipers and Dunlins were at least 4 times higher along channels than in open mudflat habitats. Infauna along channels were twice as abundant as those in the surrounding mudflats, and infauna were generally found closer to the surface. Furthermore, sediment alongside channels required less than half the force to probe, probably increasing shorebirds' overall access to prey. We conclude that shorebirds selected microhabitats near channels because of the greater food abundance and availability. Additional evidence suggested that another microhabitat, patches of red algae (Gracilaria sp.), may also have conferred advantages on foraging shorebirds. Channels may be a valuable microhabitat to consider when selecting conservation areas for shorebirds, and maintaining channels (e.g., through maintaining natural hydrology and sedimentation patterns) should be considered in management practices. Close

• 3. [Article] Nuwuvi (Southern Paiute) Ecological Knowledge of Piñon-Juniper Woodlands: Implications for Conservation and Sustainable Resource Use in Two Southern Nevada Protected Areas

  Nuwuvi (Southern Paiute) have inhabited the southern Great Basin for thousands of years, and consider Nuvagantu (where snow sits) in the Spring Mountains landscape to be the locus of their creation as ...

  Citation × Citation Citation Abstract Copy Title: Nuwuvi (Southern Paiute) Ecological Knowledge of Piñon-Juniper Woodlands: Implications for Conservation and Sustainable Resource Use in Two Southern Nevada Protected Areas Author: Lefler, Brian John Year: 2014 Nuwuvi (Southern Paiute) have inhabited the southern Great Basin for thousands of years, and consider Nuvagantu (where snow sits) in the Spring Mountains landscape to be the locus of their creation as a people. Their ancestral territory spans parts of Nevada, Utah, Arizona, and California. My research identifies and describes the heterogeneous character of Nuwuvi ecological knowledge (NEK) of piñon-juniper woodland ecosystems within two federal protected areas (PAs) in southeastern Nevada, the Spring Mountains National Recreation Area (SMNRA) and the Desert National Wildlife Refuge (DNWR), as remembered and practiced to varying degrees by 22 select Nuwuvi knowledge holders. I focus my investigation on four primary aspects of NEK. First, drawing from data obtained through ethnoecological research, I discuss how Nuwuvi ecological knowledge evolved through protracted observation and learning from past resource depletions, and adapted to various environmental and socio-economic drivers of change induced since Euro-American incursion. Second, I argue that Nuwuvi management practices operate largely within a framework of non-equilibrium ecology, marked by low to intermediate disturbances and guided by Nuwuvi conceptions of environmental health and balance. These practices favor landscape heterogeneity and patchiness, and engender ecosystem renewal, expanded ecotones, and increased biodiversity. I then consider the third and fourth aspects of NEK as two case studies that consider NEK at the individual, species, population, habitat, and landscape scales. These case studies operationalize NEK as a relevant body of knowledge and techniques conducive to collaborative resource stewardship initiatives with federal land management agency partners. In the first case study I suggest that the Great Basin piñon pines are Nuwuvi cultural keystone species (CKS), evaluating their central importance to Nuwuvi according to several criteria including number of uses, role in ritual and story, and uniqueness relative to other species. In the second case study I contend that local social institutions regulated Nuwuvi resource use in the past and in some cases continued to do so at the time of study. These local social institutions included a system of resource extraction and habitat entrance taboos that may have mitigated impacts and supported sustainable resource use and conservation. The implications of this research are that Nuwuvi ecological knowledge, disturbance-based adaptive management practices, and resource and habitat taboos are relevant to contemporary land management concerns in piñon-juniper woodlands, offering complementary approaches to adaptive management as practiced in the SMNRA and the DNWR despite divergent epistemological foundations. My research contributed to the Nuwuvi Knowledge-to-Action Project, an applied government-to-government consultation, collaborative resource stewardship, and cultural revitalization project facilitated by The Mountain Institute among seven Nuwuvi Nations, the U.S. Forest Service, and the U.S. Fish and Wildlife Service. Title: Nuwuvi (Southern Paiute) Ecological Knowledge of Piñon-Juniper Woodlands: Implications for Conservation and Sustainable Resource Use in Two Southern Nevada Protected Areas Author: Lefler, Brian John Year: 2014 Nuwuvi (Southern Paiute) have inhabited the southern Great Basin for thousands of years, and consider Nuvagantu (where snow sits) in the Spring Mountains landscape to be the locus of their creation as a people. Their ancestral territory spans parts of Nevada, Utah, Arizona, and California. My research identifies and describes the heterogeneous character of Nuwuvi ecological knowledge (NEK) of piñon-juniper woodland ecosystems within two federal protected areas (PAs) in southeastern Nevada, the Spring Mountains National Recreation Area (SMNRA) and the Desert National Wildlife Refuge (DNWR), as remembered and practiced to varying degrees by 22 select Nuwuvi knowledge holders. I focus my investigation on four primary aspects of NEK. First, drawing from data obtained through ethnoecological research, I discuss how Nuwuvi ecological knowledge evolved through protracted observation and learning from past resource depletions, and adapted to various environmental and socio-economic drivers of change induced since Euro-American incursion. Second, I argue that Nuwuvi management practices operate largely within a framework of non-equilibrium ecology, marked by low to intermediate disturbances and guided by Nuwuvi conceptions of environmental health and balance. These practices favor landscape heterogeneity and patchiness, and engender ecosystem renewal, expanded ecotones, and increased biodiversity. I then consider the third and fourth aspects of NEK as two case studies that consider NEK at the individual, species, population, habitat, and landscape scales. These case studies operationalize NEK as a relevant body of knowledge and techniques conducive to collaborative resource stewardship initiatives with federal land management agency partners. In the first case study I suggest that the Great Basin piñon pines are Nuwuvi cultural keystone species (CKS), evaluating their central importance to Nuwuvi according to several criteria including number of uses, role in ritual and story, and uniqueness relative to other species. In the second case study I contend that local social institutions regulated Nuwuvi resource use in the past and in some cases continued to do so at the time of study. These local social institutions included a system of resource extraction and habitat entrance taboos that may have mitigated impacts and supported sustainable resource use and conservation. The implications of this research are that Nuwuvi ecological knowledge, disturbance-based adaptive management practices, and resource and habitat taboos are relevant to contemporary land management concerns in piñon-juniper woodlands, offering complementary approaches to adaptive management as practiced in the SMNRA and the DNWR despite divergent epistemological foundations. My research contributed to the Nuwuvi Knowledge-to-Action Project, an applied government-to-government consultation, collaborative resource stewardship, and cultural revitalization project facilitated by The Mountain Institute among seven Nuwuvi Nations, the U.S. Forest Service, and the U.S. Fish and Wildlife Service. Close