<p> Geophagy, the consumption of mineral soil, is believed to have several benefits for herbivores. Soils high in clay are often implicated in the detoxification of plant secondary metabolites. High mineral concentrations in soils may also provide nutrients that are poorly available from plants. Local observers report that snowshoe hares (Lepus americanus) use a lick in the foothills of the Brooks Range, Alaska. Using soil from this lick and other mineral supplements, I conducted a series of feeding trials on captive snowshoe hares fed felt-leaf willow (Salix alaxensis) or a formulated ration to determine whether geophagy resulted in a physiological benefit and, if so, which soil constituents are therapeutic. When fed willow leaves, hares ate more and lost less weight when they had access to soil. Access to soil increased sodium intake and dietary ratios of sodium to potassium in hares fed willow. Soil consumption resulted in higher calcium to phosphorous ratios for both diets. Across diets, higher sodium to potassium and lower calcium to phosphorus ratios corresponded to reduced weight loss. Access to pure calcium carbonate resulted in reduced weight loss in hares fed winter dormant willow twigs, suggesting that carbonates may also be an important component of this lick. </p>

<p> This research was conducted in collaboration with rural Yup'ik residents of the Yukon River delta region of Alaska. The thesis explores traditional knowledge and conservation ethics among rural Yup'ik residents who continue to maintain active subsistence lifestyles. From the end of July through August of 2012, ethnographic field research was conducted primarily through participant observation and semi-structured interviews, documenting Yup'ik subsistence hunting and fishing practices. Research participants invited me beluga whale hunting, seal hunting, moose hunting, commercial and subsistence fishing, gathering berries, and a variety of other activities that highlights local Yup'ik environmental knowledge, practices, and ethics. Through firsthand examples of these experiences, this thesis attempts to explore what conservation means through a Yup'ik cultural lens. Documenting Yup'ik traditional knowledge offers an opportunity to shine a light on the stewardship of local people's relationship with their traditional lands. The importance of maintaining direct relationships with the natural world, eating Native foods, and passing on hunting and gathering skills to future generations help develop the narrative of my analysis. In many ways, the cultural heritage of the Yup'ik people are embodied in such practices, providing a direct link between nature and culture.</p>

<p> Within Mediterranean ecosystems, conservation and restoration action is becoming increasingly necessary to preserve biological diversity within these working landscapes. Many of these systems have been managed to increase forage production through the removal of canopy trees and shrubs, resulting in understories dominated by herbaceous species. In California, woody plant regeneration can be constrained by exotic annual grasses, particularly in the presence of grazing. <i>Quercus douglasii</i> and other oak species are known to indirectly facilitate and provide spatial refuges to native plants through competitive suppression of herbaceous productivity. Mature trees can also compete with understory recruits and shrub species, limiting their occurrences to interstitial canopy gaps and resulting in reduced competition for resources. This study surveyed the overstory composition of 34 study plots at the Sierra Foothill Research and Extension Center to determine the effects of tree canopies on the occurrence and distribution of native woody species in the undergrowth. Because other studies have shown safesites, which include rock outcroppings, woodpiles, and nurse plants to facilitate woody plant establishment in this system, the microsites containing individual plants were recorded to determine the distribution of different woody species. Multivariate regressions showed that understory plant richness and abundance increased with higher levels of canopy cover, suggesting that mature trees play a role in maintaining understory diversity. The majority of stems were found growing directly underneath the canopy, with only one species established primarily in interstitial areas. Restoration strategies can utilize the natural distributions of woody species in the understory in order to increase the survival of plantings while continuing to manage these systems for multiple ecosystem services.</p>

<p> After nearly being extirpated from the state, black bears in Maryland have rebounded to a point where recreational harvest has now become an important management tool. Having a better understanding of bear population parameters, movements, and harvest vulnerability allows managers to implement hunting more effectively and responsibly. To estimate demographics of the Maryland bear population, we implemented noninvasive genetic sampling of bear hair during summer 2011. We used a model-based sampling design that allowed us to collect samples more efficiently. We used presence-only maximum entropy (Maxent) modeling to classify the study area based on predicted probability of bear occurrence, and allocated the majority of our hair snares to areas with high or medium probabilities. Using microsatellite analysis and mark-recapture methods, we estimated the bear population at 701 individuals. This represents a nearly doubling of the population since the previous estimate in 2005. Our density estimate (0.25 bears/km²) is comparable to other estimates from southeastern and mid-Atlantic states. Our sampling approach did lead to more efficient sample collection, with more hair samples collected at snares located in areas with predicted high or medium probability of bear occurrence than those in low probability areas. However, in the eastern portion of our study area, where bear occurrence is presumed to be much lower, our sampling effort seemed insufficient to collect enough samples for reliable abundance estimation. As a first step toward quantifying harvest vulnerability, we used Global Positioning System (GPS) units to record movements and spatial behaviors of 108 bear hunters during the 2005&ndash;2007 Maryland bear hunting seasons. Median values showed that hunters traveled 2.9 km per hunting event, but only 0.6 km from their starting point. Hunters did not seem to show any preferential use of areas based on the landscape metrics we examined (e.g., elevation, distance from nearest road) except cover type, where 81% of locations were in deciduous forests. We found few differences between spatial behaviors of groups of hunters based on harvest success, residency, and previous bear hunting experience, as classified using post-hunt mail surveys. One notable difference is that successful hunters used steeper slopes than unsuccessful hunters. We also found that hunter perceptions of total distance traveled and distance from nearest roads were often highly inaccurate, showing that hunter surveys are not a useful tool for collecting those data. For Garrett County, Maryland, we used the hunter locations to create a Maxent model of the spatial distribution of harvest pressure. We also created a model using fall telemetry locations of female bears and compared the models to identify areas of high (i.e., high hunter and high bear occurrence) and low (i.e., low hunter and high bear occurrence) harvest vulnerability. Both models showed higher probability of occurrence on public lands. Both high and low vulnerability areas comprised small portions of the county. The low vulnerability areas included 9 larger blocks (>1 km²), which were 2.3 times steeper, 2.0 times farther from roads, and 1.5 times farther from streams than the medians for the study area. Those characteristics may limit hunter access to and use of the areas. Our predicted high vulnerability areas did not correspond to most previous bear harvest locations, indicating that our definition of harvest vulnerability often does not translate to actual harvest. Finally, we used GPS collars to track female bear locations in Garrett County and examine home range dynamics. Fixed kernel estimates for annual, spring, summer, and fall home ranges were 10.40 km², 8.93 km², 16.08 km², and 19.35 km², respectively. Fall and summer home ranges were larger than spring home ranges, but summer and fall ranges were similar. Solitary females had mean spring home ranges 6.9 times larger than females with cubs-of-the-year, but ranges did not differ during other seasons. Bears exhibited high levels of home range fidelity, with home range centroids shifting little among seasons or years. Intraspecific overlap of home ranges occurred during all 3 seasons, but was most common in summer. The results of this study provide Maryland bear biologists and managers with essential information about the state&rsquo;s bear population. Home range estimates represent important baseline information to determine appropriate spatial scales of management. The abundance estimates will be used to set proper harvest quotas with the goal of slowing the bear population growth. The hunter movement analysis and harvest vulnerability modeling may be used by managers to adjust harvest regulations to increase the efficacy of the hunting seasons.</p>

<p>Stream restoration is being conducted throughout the world at unprecedented rates to address stream channel degradation and water quality concerns. Natural Channel Design (NCD) is a common method used for restoration and has received governmental endorsement; however, the effects of NCD on channel stability and ecosystem functioning are poorly studied. We examined the effects of a reach-scale NCD project on channel stability, riparian vegetation, and water quality along the Cacapon River, West Virginia using a before-after-control-impact design and determined that restoration increased the abundance and diversity of woody vegetation, but had minimal effects on streambank stability and water quality. Increased erosion rates in some portions of the restored reach were attributed to differences in pre-restoration stability, vegetation removal, and soil composition among sub-reaches. No differences in in-stream concentrations of total phosphorus, nitrates, ammonia, or total suspended solids were detected following restoration; however, in-stream turbidity was drastically increased during construction. This study is a clear example of the value of monitoring streambank migration, vegetation communities, and soils to evaluate the effects of stream restoration and to provide insight on potential reasons for treatment failure. Ideally, pre-restoration monitoring should be used to inform project design by determining restoration potential of areas selected for restoration. </p><p> As a surrogate for process monitoring, we created a maximum entropy model of streambank erosion potential (SEP) in a Geographic Information System (GIS) framework to prioritize sites for management and to determine which variables in the watershed are associated with excessive rates of streambank erosion. Model development included measuring erosion rates throughout a central Appalachian watershed, application of a quantitative approach to locate target areas for management termed Target Eroding Areas (TEAs), and collection of environmental data throughout the study extent using high resolution, remotely sensed data. A likelihood distribution of TEAs from occurrence records and associated environmental variables over our study extent was constructed using the program Maxent. All model validation procedures indicated that the model was an excellent predictor of TEAs, and that the major environmental variables controlling these processes were streambank slope, soil characteristics, shear stress, underlying geology, and riparian vegetation. A classification scheme with low, moderate, and high levels of erosion potential derived from logistic model output was able to differentiate sites with low erosion potential from sites with moderate and high erosion potential. This type of modeling framework can be used in any watershed to address uncertainty in stream restoration planning and practice. </p><p> To address the need for accurate, high resolution estimation of streambank erosion, we also explored the role of laser scanning for estimating streambank migration and volumetric sediment loss. This was accomplished by comparing estimates of streambank migration and volumetric sediment loss derived from repeated erosion pin, streambank profile, and combined airborne and terrestrial light detection and ranging (LiDAR) surveys. Results indicated that LiDAR derived estimates were larger and highly variable compared to estimates derived from erosion pin and streambank profile surveys, which more accurately represented change along the study reach. Inflated LiDAR estimates were most likely the result of combining high resolution terrestrial LiDAR with relatively low resolution airborne LiDAR that could not effectively capture topographic features such as undercut banks. Although cost-prohibitive in some cases, repeated terrestrial LiDAR scans would likely circumvent these issues with higher point densities and better scan angles facilitating more accurate representation of streambank geometry, ultimately providing more accurate estimates of channel change. </p>

<p> The Golden-winged Warbler (<i>Vermivora chrysoptera</i>) is an imperiled migratory songbird that nests in young forest habitats of eastern North America. As such, this species has recently been the focus of an intensive multi-year, range-wide, breeding ecology study. A major focus of this research involved spot-mapping color banded males to examine relationships between nesting success and territory-scale habitat variables. I compared differences in space and habitat use of individual male Golden-winged Warblers that were monitored using both spot mapping and radio telemetry. An individual's telemetry delineated use area was on average 3.6 times larger than its spot-mapped territory. Almost half (46%) of all telemetry locations were located outside their respective male's spot-mapped territory. Number of saplings was higher in telemetry use areas (22.49 &plusmn; 2.14) than spot-mapped territories (11.80 &plusmn; 1.86). Although the exact motive for extra-territorial movements is unknown, foraging and/or suggestive observations of extra-pair copulation are likely motivating factors. The results of my study suggest Golden-winged Warblers are seeking resources outside their spot-mapped delineated territories. Furthermore, Golden-winged Warblers were found to have more telemetry locations in mature forest than found through spot-mapping. Ultimately, spot mapping alone does not accurately reflect Golden-winged Warbler space use and habitat needs.</p>

<p> Hybrid poplars are a short rotation woody crop grown for a variety of target markets including paper pulp, saw timber, and biofuels in the Pacific Northwest. Development of pest control strategies within hybrid poplar plantations over the last several decades has focused on controlling foliar feeding herbivores and wood boring pests, and has overlooked the epigeal arthropod community. Understanding this unstudied suite of organisms would allow pest managers to better evaluate the impact their management strategies have on the poplar agroecosystem. Qualitative surveys of the arthropod communities in hybrid poplar plantations and nearby native habitats demonstrated that a greater arthropod diversity persists in the surrounding native areas. Additionally, the poplar plantation's epigeal arthropod community was composed of species found within sampled native areas. </p><p> Historically poplar research focused on protecting trees in the years following establishment through harvest from emerging pests while discounting cutting mortality by replanting areas of failure. Describing unrooted cutting transplant morality and distribution within newly established planting block could provide a risk assessment tool that growers could utilize to evaluate their potential crop loss. It was determined through the examination of damaged cuttings that several pests were responsible for diminishing establishment success. Identification of these risks led to the development of a management strategy to reduce mortality in newly planted areas. Soaking cuttings in imidacloprid for 48 hrs provided superior herbivore protection for unrooted cuttings until root formation allowed for uptake from chemigation treatments. </p><p> An additional study was motivated by the increased concern in growing `clear wood' as poplar has migrated from pulp to saw timber. The accompanying renewed interest in reducing insect galleries in mature trees led to the exploration of deploying a mass trapping, or trap out, effort to reduce populations of <i> Prionoxystus robiniae</i> (Lepidoptera Cossidae) in specific areas of a hybrid poplar plantation. We show that a trap out effort of roughly 5 pheromone-baited traps/ha decimated <i>P. robiniae</i> populations in treated areas throughout the trap out effort and three years post application.</p>

<p> While range-wide population declines have prompted extensive research on greater sage-grouse (<i>Centrocercus urophasianus</i>), basic information about southern periphery populations, such as the Bald Hills population in southern Utah, has not been documented. The objective of this research was to determine habitat preferences and space use patterns of the Bald Hills sage-grouse population which occurs in an area of high potential for renewable energy development. I tracked 66 birds via VHF telemetry in 2011 and 2012 and surveyed vegetation plots throughout the study area. I found that the population was primarily one-stage migratory with seasonal distributions that did not correspond well with previously developed suitable habitat maps (based on local biologist knowledge and lek data) for all seasons; I also found that mean home range sizes ranged from 82 km² to 157 km².</p><p> Nesting hens did not select for any measured vegetation characteristics within the study area, while brood-rearing hens selected for high forb cover. Birds at summer sites (non-reproductive bird locations during the summer season) selected for greater grass and forb cover and lower shrub cover compared with random sites. Overall, Bald Hills sage-grouse used areas with greater shrub canopy cover and lower grass and forb cover than recommended in habitat guidelines. </p><p> Ten predictor variables were used to model suitable seasonal habitat using Maximum Entropy (maxent). All models were created for the Bald Hills population and projected to the Bureau of Land Management Cedar City Field Office management area and produced excellent model fit (AUC > 0.900). The Bald Hills population had similar nesting and winter habitat preferences as other populations but different brood-rearing and summer habitat preferences. I found local management techniques to be an important driver of seasonal habitat selection; birds selected for areas that had undergone habitat treatments (such as broadcast burn and crushing) within the previous 10 years. My results indicated the Bald Hills periphery population occupies marginal habitat and has adapted unique seasonal habitat preferences. Managers of isolated, fringe, and low-density populations should develop locally specific management guidelines to address the unique adaptations and ensure the persistence of these populations. </p>

<p> Snowshoe hare (<i>Lepus americanus</i>) survival depends on the interaction of habitat characteristics with numerous biological and environmental variables. In boreal regions where considerable habitat heterogeneity exists, hares balance food availability with predation risk by moving among habitats seasonally, but it is largely unknown how often they move at shorter time scales. I investigated the seasonal effects of habitat, weather, and individual hare characteristics on survival and movement in two common but fundamentally different boreal habitats. Survival was highest in summer, for hares with higher body condition, and in black spruce rather than early successional forest. Hares moved among core use areas in different habitats twice per day on average, using more open areas at night when they were presumably feeding on preferred browse. Movement rates were lowest in mid-afternoon when hares appeared to be resting under dense cover. Behavior of individuals varied greatly with some hares repeatedly moving up to 1 km between defined patches in less than 5 hours and others remaining roughly within a 1 ha area. These findings illustrate the complexity of snowshoe hare ecology in an area where habitat variation promotes daily movement of hares among radically different habitats over a few hundred meters.</p>

<p>The recent research focus on integrated multi-trophic aquaculture (IMTA) is redefining the aquaculture industry's approach to intensive aquaculture. More sustainable farm model systems that include multiple farm products with integrated trophic levels are being developed. While these systems may be economically and environmentally more sustainable, it is important to realize that integrating farm products also changes disease risk on farms. This is illustrated by examining how finfish disease risk can increase or decrease depending on the pathogen in a simple finfish / blue mussel (<i>Mytilus edulis</i>) IMTA system. Mussels bio-accumulate and repackage the opportunistic pathogen, <i>Vibrio anguillarum,</i> into infectious fecal particles increasing the potential risk of infection and creating new transmission pathways. In contrast, mussels appear to inactivate the viral pathogen, Infectious Salmon Anemia Virus (ISAV) and potentially serving a role in reducing the transmission of the virus onto and off of IMTA farms. </p><p> To understand disease risk on IMTA farms, it is no longer adequate to simply investigate how a given pathogen interacts with its host under a range of environmental conditions. Evaluating the disease risk in IMTA systems requires a better understanding of how pathogens may potentially interact with all of the components of the farm system, while recognizing new potential pathways that may be created or enhanced within and by the system its self. Through a more comprehensive understanding of these potential interactions farmers can apply a range of bio-security and best management practices to limit the risk of disease on IMTA farms. With good management IMTA farms should not increase the risk of disease, but may actually reduce the spread of pathogens in some situations. </p>