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The Relationship Between Deuterium Excess and Uranium Groundwater Concentrations in Whitehall, Montana
Get PDFUranium can become elevated in the environment and pose a human health risk to water resources. Therefore, it is important to understand the origin, transport and concentration of uranium in the environment. With this exploratory study we propose that deuterium (δ2H) excess may be a viable way to study uranium groundwater concentrations that originate from the surface. The Boulder Batholith of southwestern Montana has been associated with varying levels of uranium. The Whitehall, MT area includes the Boulder Batholith as a geologic unit. We collected 23 water samples and compiled data from a study done by the United States Geological Survey (USGS) within the area of Whitehall, MT. With a linear regression we show that there is a significant negative relationship between deuterium excess and uranium water concentrations. As expected we showed that there is a significant positive, linear relationship between uranium water concentrations and nitrate water concentrations. As expected we also showed that there is a significant positive, linear relationship between calcium carbonate and uranium groundwater concentrations for the compiled USGS data. The results of a Wilcoxon rank sum test showed that median uranium concentration for wells close to ponds is 14.5 μg/L higher for our data added to the USGS data. These results may be consistent with a model that involves insoluble uranium being transported in suspension and settling out in ponds where an influx of nitrates and/or carbonates react to produce higher concentrations of water-soluble forms of uranium. We suggest that the relationship found between uranium concentration and deuterium excess in water samples may be related to the higher rates of evaporation in ponds. Thus, in this specific hydrologic environment of valley ponds close to the Boulder Batholith source, deuterium excess may serve to help predict levels of uranium concentrations
The History of PNLA in Washington State
No full textThe author presents a history of the Pacific Northwest Library Association in Washington State
A Small Rna that Regulates Pyrimidine and Methionine Metabolism is Necessary for Establishing Coxiella Burnetii's Intracellular Niche During Early Stages of Infection
No full textCoxiella burnetii is an obligate intracellular gammaproteobacterium and zoonotic agent of Q fever in humans. We previously identified 15 small RNAs (sRNAs) in C. burnetii with differential expression in the large and small cell developmental forms grown axenically and in infected host cells. Here, we describe the function of one of these sRNAs, termed Coxiella burnetii small RNA 12 (CbsR12). CbsR12 is highly expressed in both large- and small-cell variants in vitro, and is the dominant non-tRNA/rRNA/tmRNA transcript in both morphotypes during mammalian tissue culture infection. Through a combination of in vitro and in vivo assays, we have identified several targets of CbsR12. Of these, we have confirmed that CbsR12 binds to and upregulates translation of carA transcripts coding for carbamoyl phosphate synthetase A; an enzyme that catalyzes the first step of pyrimidine biosynthesis. In addition, Cbsr12 binds and downregulates translation of metK transcripts coding for S-adenosyl methionine (SAM) synthase, an essential component of the methionine cycle. Furthermore, we have established that CbsR12 is necessary for full expansion of Coxiella-containing vacuoles (CCVs) and is linked to growth rate in a dose-dependent manner in the early phase of infection of Vero and THP-1 cell lines. This is the first characterization of a trans-acting sRNA of C. burnetii and the first description of a bacterial sRNA that regulates carA and metK expression. This study also illustrates the utility of transposon insertion mutants in elucidating Coxiella’s sRNAs and the importance of sRNA regulation in establishment of the intracellular CCV nich
Examining the Relationship Between Injury and Dominance in The Alpha Female Wolves of Yellowstone National Park
No full textThe social dynamics of wolf packs have been heavily studied, and nowhere as extensively as in Yellowstone National Park (YNP) since the reintroduction of gray wolves (Canis lupus) in 1995. The objective of this study is to gather data on the impact of injury of alpha female wolves in Yellowstone, specifically the effect of injury on their dominant status. Injury is a serious threat to wild wolves in the park, who may sustain several injuries during their average lifespan of 5 years. Female wolves may only have a few litters of pups in their lifetime, and the alpha female is the primary breeder in a pack. There have been multiple documented cases of alpha females sustaining injuries and subsequently losing their status to another related female. We collected observational data on four established wolf packs in the Northern Range of YNP, focusing primarily on wolves 907F and 969F, two sisters who alternated as dominant females of the Junction Butte Pack from 2017 to 2019. We also analyzed observational data on wolves 870F and 970F, a second pair of sisters who alternated as dominant females of the same pack from 2012 to 2015. The results of this project will add to our understanding of the long-term impacts of injury in alpha females on pack dynamics. Understanding this issue is a key component of wolf conservation in the Greater Yellowstone Ecosystem
Assessing Occupancy for Montana Species of Greates Inventory Need
No full textMontana non-game species classified as Species of Greatest Inventory Need (SGIN) are not sufficiently monitored by standard ecological monitoring programs, typically because they are locally rare or cryptic, thus evading detection. Yet, these species are often those for which understanding conservation status is most important. We are developing a tool to characterize the survey effort needed to attain estimates of occupied suitable habitat, while accounting for species characteristics and logistical constraints, and incorporating flexible tools recently presented in the scientific literature. Concurrent with tool development, we have used this approach to examine survey designs for assessing suitable habitat occupancy by Great Gray Owls. We identified a survey strategy with sufficient power to estimate occupancy of this inconspicuous species using a combination of automated recording units and ground call-playback surveys that can be employed in the coming years. Understanding effort required to obtain occupancy estimates with acceptable bias and precision can support survey design for species conservation work as well as informing whether existing monitoring datasets have sufficient power to address information needs. We aim for this tool to inform ongoing survey efforts for Species of Greatest Inventory Need and to facilitate survey planning for species without survey protocols underway
Demographic Fragmentation of a Protected Wolverine Population Bisected by a Major Transportation Corridor
No full textRoads fragment terrestrial ecosystems around the globe, but the effects of this fragmentation on biodiversity remain poorly understood. Wolverines (Gulo gulo) are snow-dependent carnivores that occur at low densities and they exhibit low genetic diversity at the southern extent of their range where they are snow-limited, rare and fragmented by human development. Therefore, understanding the effect of roads on population connectivity is crucial to effective wolverine management in a changing climate. We examined whether the Trans-Canada Highway, Canada’s largest east-west transportation corridor, affects wolverine movement and gene flow in the Canadian Rocky Mountains. We used noninvasive genetic sampling methods to collect DNA samples (i.e. hair, scat) from Banff, Kootenay, and Yoho National Parks and provincial lands in British Columbia and then used population and individual-based genetic analyses to quantify genetic structure of the wolverine population across the highway in the national parks complex. We collected 2586 DNA samples between 2010 and 2013 from which we identified 49 unique individuals (29 males, 20 females). We detected equal numbers of males and females that crossed the highway (4 males, 4 females); however, dispersal and gene flow were affected differently in the two sexes by the transportation corridor. We detected weak population structure in males and relatively strong genetic differentiation in females spanning the highway. Our results demonstrate that sex-biased dispersal across a major highway can lead to genetic isolation and demographic fragmentation in a protected carnivore population, highlighting the urgent need to maintain connectivity for wildlife species over an expanding road network
Estimating Carnivore Density Using Spatial Capture-Recapture Models: Sampling Designs and Potential Pitfalls
No full textSpatial capture-recapture (SCR) models have improved the ability to estimate densities of rare and elusive animals. However, SCR models have seldom been validated even as model formulations diversify to incorporate new sampling methods and/or additional sources of information. The relationship between encounter probabilities, sources of additional information, and the reliability of density estimates, is poorly understood but crucial to assessing reliability of SCR-based estimates. We used a simulation-based approach that incorporated prior empirical work on mountain lions in western Montana to assess the accuracy and precision of density estimates from SCR models using direct search effort. Our simulations focused on understanding the consequences of: 1) variable probabilities of encounter generated from different levels of search effort, and 2) including additional spatial information from collars. Overall, we found that although low search effort resulted in sparse datasets and highly biased and imprecise estimates of density (relative bias, RB = 0.71, coefficient of variation, CV = 1.16), a combination of increased effort and/or additional information generated unbiased and precise density estimates (e.g., moderate effort and 4 collars, RB = -0.004, CV = 0.19). This work suggests that reliable density estimates can be generated by multiple sampling designs such that additional spatial information from collars can be used to supplement direct search effort when resources are limited, or by increasing search effort when collaring is impractical. Using the open-source code for our simulation-based approach, we further offer recommendations on sampling designs for SCR-based density estimation
Methods to Estimate Recruitment for Social Species with Limited Data
No full textPopulation dynamics for social species depend on hierarchical demography that links local, group-level processes to overall population growth. Many social species cooperatively breed, thus recruitment of offspring is affected by both population- and group-level processes. Traditional methods to estimate recruitment for a species that cooperatively breeds may be insufficient because they do not account for hierarchical demography. Furthermore, for a species that is broad-ranging, rare, or elusive, recruitment data may be too difficult or costly to collect. Our objective was to develop a method to estimate recruitment for a social species that accounts for hierarchical demography and does not rely on recruitment data. We developed an integrated population model (IPM), with both population- and group-level processes, to estimate recruitment in a social species. We were able to estimate recruitment from the IPM without data because changes in abundance are a function of survival and recruitment and we had data for survival. We tested the model using simulated datasets under five scenarios without recruitment data. For all five scenarios we ran models with and without the group-level process to determine if hierarchical demography improved estimation. Simulations demonstrated that the model performed well under most scenarios and provided unbiased estimates of recruitment. We found that explicitly incorporating hierarchical demography was important for estimating recruitment in social species. This model can easily be adjusted to estimate recruitment for any social species. Further, by removing the group-level process this model can be used to estimate recruitment for a non-social species when data are lacking