The Forest Service faces significant climate change-related management challenges. Understanding employee perspectives on climate change will inform potential strategies to address these challenges. By analyzing data from key informant interviews and an internet survey of Forest Service employees in the Intermountain West, this study examined how Forest Service employees view and approach climate change, assessed how they perceive barriers to and opportunities for climate change adaptation within the National Forest System, and compared their perspectives across the organizational hierarchy, from district level to national policy making. The results show that although forest managers consider climate change a concern for the agency in general, they do not necessarily see how it affects the work they do personally. Although they tend to agree that climate change should be a high priority for the agency, their own ability to incorporate adaptive practices into managing a National Forest is limited by various constraints, including a lack of time, funding, and personnel, a lack of direction for on-the-ground management, and a communication gap, which has inhibited climate change-related knowledge transfer within the agency. Thus, more effective communication is needed to help forest managers see how climate change affects various aspects of forest ecosystem health in their own National Forests or districts, how climate change poses challenges to forest resilience, and what can be done to incorporate climate change considerations into their own work. The agency needs to focus on building trust, especially across its hierarchical structure, and on encouraging both vertical and horizontal information flow among employees to facilitate scientific knowledge sharing and to enhance formal and informal social networking for increased collaboration. The agency also needs to create more opportunities for district-level employees to provide feedback and get involved in climate change-related policy making, as they are a crucial source of local knowledge and experience and can be invaluable in problem-solving within the National Forest System. The insights from this study not only contribute to the Forest Service’s continuous efforts to adapt to climate change but also shed light on strategies that can be tailored by other natural resource agencies to address various management challenges within the context of global environmental change.

"Since the development of Ogden Bay Waterfowl Management Area in 1937, the Canada goose (Branta canadesis moffitti) population increased to a peak in 1949 and then declined slightly. Nelson (1954) noted that the decrease in population was probably due to either a change in habitat or increased hunting pressure. In recent years, direct band returns have indicated a high mortality rate in the population. This project was initiated to determine the relative stability of the Canada goose population and to measure, as closely as possible, the effect of a high mortality rate upon the nesting population. To estimate the stability of a goose population, three factors must be known: (1) the production rate, (2) the mortality rate, and (3) the faithfulness of homing and degree of dispersal of the population. Through knowledge of these three factors, it is possible to estimate the stability of the population, but if any management changes must be undertaken to stop the declining population, the factors that are causing the downward trend must also be understood."

The Pantanal wetland of Brazil is an important area for the conservation of jaguars (Panthera onca) and a stronghold for the species. Although our knowledge of jaguar ecology has increased since the first field studies in the mid 1980’s, a detailed study of this cryptic species remains challenging. In the following chapters, we investigated the ecology of jaguars in the southern Pantanal of Brazil. In Chapter II, we examined the foraging ecology of jaguars, documenting predation rates, patterns, and species killed. We found individual jaguars differed in the selection of their prey. There were differences in the proportion of native prey versus cattle killed by individual cats. We found that cattle (31.7%), caiman (24.4%), and peccaries (21.0%) comprised the majority of their kills. The mean predation rate on all prey for all jaguars combined was 5.1 ± 5.0 (SD) days between kills. In Chapter III, we described jaguar habitat use and spatial patterns of predation in relation to vegetation and other landscape attributes. Jaguars used some habitats disproportionatelly to their availability both in the wet and dry seasons. Forest and shrubland habitats were generally selected by jaguars. However, the type of vegetation did not have an influence on the locations of prey killed. Contrary to expectations, jaguars did not select forested habitats nor did they avoid open fields to make kills, but killed prey in these habitats proportionatelly to their availability. Our results do not support earlier findings about jaguar habitat use in the southern Pantanal but illustrate the highly opportunistic nature of jaguars. In Chapter IV, we examined space use, site stability and fidelity, movement rates, and interactions of jaguars. Our results suggested a pattern of spatial avoidance among females during the wet season. Among males, home range overlap was extensive, both in the wet and dry seasons, suggesting males did not retain exclusive ranges. Our study provided insights into the dynamic land tenure system of jaguars. Future research would benefit from radio-collaring a large number of individuals and monitoring them over a longer time span to provide a better understanding of their spatial ecology and social interactions.

The importance of actinomycetes in the soils was generally overlooked until about 1913. The investigators Hiltner and Stormer and Beijerinck began systemtaic study of their occurrence and role in soil fertility. The work done by these men and others since 1913 has proved actinomycetes to occur abundantly in most soils of the world. This work done by these men and others since 1913 has proved actinomycetes to occur abundantly in most soils of the world. This work has also proved the function of these organisms to be that of decomposing highly resistant materials such as humus and complex polysaccharide compounds. More recent work by Waksman and coworkers has established the importance of these organisms in the study of antibotics. Surveys of actinomycetes have since been made of soils in the United States and countires abroad; however, no survey has been made of soils of the great arid region of the United States. Utah soils are typical of the soils found in this region. The purpose of this study is to determine the number of actinomycetes in Utah soils in relation to the total microflora of the soil, and to appraise some of their antagonistic properties. This investigation has been primarily limited to 49 samples taken from the soils of Utah which have been studied and described by the United States Department of Agriculture.

Widespread habitat degradation and fragmentation has significantly altered the distribution and abundance of salmonids across the Western United States. To effectively conserve these fish, managers need tools to evaluate habitat quality in physically diverse streams and watersheds. Traditionally, habitat assessment for stream fish has focused on the physical characteristics of sites. Thus, such research has often overlooked important biological factors, such as the availability of prey or the presence and abundance of competitors or predators. In recent years, however, researchers have considered habitat from both physical and biological dimensions. Bioenergetics models offer a way to combine the both the biotic and abiotic characteristics of streams into one currency (i.e., energetic value) of habitat selection and habitat quality. These models take into account both physical habitat characteristics (i.e., depth, velocity, substrate, and temperature) and the availability of food from drifting insects to predict favorable locations for foraging fish, and have been extended to make reach-scale predictions of total habitat capacity. Drift-foraging, bioenergetics models are increasingly being used to evaluate habitat quality and quantity, as well as carrying capacity of the sites they are run at. However, many of these bioenergetics models have been developed and applied for salmonids at sites whose populations are well below carrying capacity. Therefore, it is essential to test the predictions of these models on populations of salmonids that are abundant. To address these concerns, I tested a bioenergetics model that Wall et al. (2016) applied to inform habitat management in the western US for cutthroat trout. I surveyed the spatial location of Bonneville cutthroat trout (BCT; Oncorhynchus clarkii utah) in the Logan River, Utah, a system where one of the most abundant populations of BCT reside, to determine if the fish were using locations with a high energetic value, predicted by a net rate of energy intake (NREI) modeling framework. I conducted snorkel surveys in both summer and fall to assess whether the modeled predictions were robust to changes in drift, temperature, or discharge. I also tested whether sampling estimates of BCT abundance were related to the NREI model predicted carrying capacity, or the proportion of suitable habitat (i.e., NREI > 0.0 J·s-1). Last of all, I tested whether the observed biomass of BCT were related to the mean NREI at each study site. I found that the majority of observed fish occupied focal positions that (i) had positive NREI and (ii) had NREI values that were significantly greater than the site mean. I also found that the simulated carrying capacity predicted for each site was significantly, positively related with the maximum BCT densities observed between 2001 and 2015 (R2=0.93, P=0.009). However, observed BCT densities and biomass were unrelated to the proportion of suitable habitat and the mean NREI at sites, respectively. I concluded that drift foraging bioenergetics models are useful tool for pin-pointing bioenergetically favorable locations within sites and discriminating capacity between sites for BCT and other similar trout species.

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Animals across Earth are shifting or expanding their ranges because of climate change. These are climate migrants. Although climate migrants are well-documented, their impacts on recipient ecosystems are not. Climate migrants that are also ecosystem engineers (species that modify or create habitats) will likely have profound effects on ecosystem functioning. The Atlantic marsh fiddler crab, Minuca pugnax, is a burrowing crab that recently expanded its range into the northeast United States. The historical range of M. pugnax was between southern Cape Cod, Massachusetts and Daytona Beach, Florida (Grimes et al., 1989). In 2014, Johnson (2014) found that M. pugnax was found to have extended its northern limit to New Hampshire, moving north from Cape Cod into the Gulf of Maine. We tracked the M. pugnax population within the Great Marsh, in northeast Massachusetts, since it was first detected in 2014 using burrow counts. Thus, the objective of my first chapter was to quantify the densities of M. pugnax within the Great Marsh in northeast Massachusetts using camera traps. The second objective was to measure the relationship between burrow counts and fiddler crab densities. Because burrow counts can overestimate fiddler-crab density, we used camera traps to determine the relationship between burrow densities and fiddler-crab densities in 2019. The burrow count surveys show a 6-fold increase in M. pugnax density in the Great Marsh from 2014–2019. This result indicates that the fiddler-crab population in the expanded range is established and growing. Based on burrow counts, however, the density of M. pugnax in the expanded range (6 burrows m–2) is much lower than those found in the historical range (between 75 - 300 burrows m–2). Based on camera traps, we determined that burrow counts overestimated fiddler-crab densities by 47% in 2019. Stated another way, there was, on average, one crab detected for every two burrows observed. However, this is strictly for crabs that were observed and does not account for ovigerous females who are known to incubate deep in their burrows. Therefore, further work will be needed to adjust our estimates. Minuca pugnax is an ecosystem engineer that can influence saltmarsh functioning and the magnitude of that influence is related to its density. Following, the objective of my second chapter was to examine its ecological impact on salt marshes. In a control-impact study, we found that when crabs were present, Spartina alterniflora plant height was 9% lower, aboveground biomass was 40% lower, belowground biomass was 30% lower, benthic microalgae biomass was 44% lower, bulk density was unaffected, and sediments became more reduced. Our results show that M. pugnax can have strong ecological impacts in its expanded range, which has implications for other salt marsh functions such as carbon storage and accretion. In its historical range, M. pugnax promotes the aboveground biomass of Spartina as a result of burrowing (it does not eat live Spartina) suggesting a plant-crab commensalism. We found the opposite pattern in M. pugnax’s expanded range. Thus, what was a commensalism appears to be an amensalism in the expanded range. Our results imply that not only can engineering climate migrants have strong ecological impacts but also that those impacts may be the opposite of what has been historically seen.

Restoration of eastern oyster (Crassostrea virginica) reefs in the Chesapeake Bay and its tributaries is important, as oyster reefs provide habitat for temperate estuarine communities and shoreline protection. Oysters that settle in crevices, such as those found on natural shell substrates, suffer low mortality, but natural shell is becoming a limited resource in the Chesapeake Bay. Finding an alternative settlement substrate that is complex like natural shell and mimics the benefits of shell substrates with less expense could be the best way to encourage oyster recruitment and survival. The two main goals of this experiment were to (1) understand which artificial substrate type (granite stone, oyster castle, diamond, c-dome, and x-reef) promotes the highest oyster recruitment and survival compared to natural shell and (2) determine the effects of reef presence on macrofaunal community structure and productivity. It was hypothesized that a new settlement substrate, oyster diamonds, given the sloping surfaces with large surface area, will be best for oyster recruitment. Additionally, it was hypothesized that oyster reef presence will substantially enhance macrofaunal community abundance and increase macrofaunal productivity compared to unstructured sediment. To address these goals, infaunal macrofauna and sediment samples were taken at three experimental sites and two control sites along the York River in June 2021. Then, two replicates of each of six reef types were deployed in a randomized block design at each of three experimental sites. The reef types included loose oyster shell, granite, oyster castles, oyster diamonds, c-domes, and x-reefs. The fall after deployment, the structures were sampled for oyster density and shell height. One year after deployment, the structures were physically sampled, removing oysters to determine oyster density and biomass, and the macrofaunal community associated with the reefs. Control sites were sampled for benthic infauna and sediment analyses. Oyster densities and biomass were extremely high and were highest on the loose shell reef (9,852 oysters/m2 and 743 g AFDW/m2 based on model estimates), and the x-reefs had the second-highest recruitment and biomass (3,816 oysters/m2 and 531 g AFDW/m2 based on model estimates). Prior to deployment of reefs, control and impact sites had similar density, biomass, and diversity of macrofauna, but one year after reef deployment, the reef impact sites had higher densities, richness, diversity, biomass, and secondary productivity of macrofaunal organisms than the control sites with the impact sites having 145 times greater secondary productivity than the controls. The diversity among reef types did not vary but the granite reefs had the highest secondary productivity overall. All reef structures showed successful oyster and macrofaunal community recruitment based on Chesapeake Bay Fisheries Goal Implementation Team metrics and densities were among the highest for alternative substrates. Based on the results of this study, researchers and managers could choose from a variety of successful alternative reef types. Based on restoration goals, the use of different reef types could lead to differences in the achievement of goals.

No description available.

No description available.