Theses and Dissertations at Montana State University (MSU)

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    Grizzly bears and humans at two moth aggregation sites in Wyoming
    (Montana State University - Bozeman, College of Agriculture, 2020) Nunlist, Erika Ana; Chairperson, Graduate Committee: Bok Sowell
    Human interactions with grizzly bears at moth sites is an important management issue because of the potential for displacing bears and the implications for human safety. The objective of our study was to quantify human and bear use overlap and interactions associated with two of the most human-accessible moth sites in the Greater Yellowstone Ecosystem. Our field work was conducted during the summers of 2017 and 2018. We conducted systematic bear surveys and analyzed the data using a resource selection function. Human use was quantified through trailhead monitoring, peak log entries, and opportunistic documentation. Hiking route data were collected using GPS tracking units distributed at trailheads. Human-bear overlap was assessed by comparing human and bear use and validated against interaction location data. We conducted 293 surveys and documented 266 bear locations. Landscape covariates describing temperature, moisture, terrain, and landcover were important to grizzly bear use. We recorded very different human use levels between the two study sites (North site: 3 groups/year; South site: 35 groups/year). Human use at the North site was dispersed and associated with hunting and use at the South site was most often associated with peak climbing and/or bear viewing and was concentrated along one primary route to the peak. We documented a total of 43 interactions (at the South site only) and obtained location data for 29 of those interactions. During human-bear interactions, bears strongly avoided human presence 80% of the time and had no apparent reaction 20% of the time. Most interactions occurred immediately around the South site peak (14/29) or along the primary route (12/29), areas that we identified to have high human and bear use overlap. We confirmed significant human safety and bear disturbance management concerns. Human safety concerns were most apparent in uneducated, and consequently unprepared, mountain climbing groups with small groups sizes (<4 people, n=64/70). Bear disturbance concerns were apparent from numerous interactions that resulted in bear displacement. Overall, we suggest that the concern expressed by managers over human and bear use overlap at the South site is warranted. Mitigation efforts should be explained in a management plan.
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    Serological studies of moth proteins with special reference to specific immune bodies and their phylogenetic significance
    (Montana State University - Bozeman, College of Agriculture, 1933) Martin, Saxon
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    Determination of host races in three insect species attacking Dalmatian toadflax and yellow toadflax in North America
    (Montana State University - Bozeman, College of Agriculture, 1991) McDermott, Gregory James
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    Evolution of the molecular mechanisms of pheromone reception in European and Asian corn borer moths
    (Montana State University - Bozeman, College of Agriculture, 2010) Allen, Jean Elaine; Chairperson, Graduate Committee: Kevin Wanner.; Kevin W. Wanner, Andrew S. Nichols, Peggy L. Bunger, Stephen F. Garczynski, Charles E. Linn Jr., Hugh M. Robertson and Charles W. Luetje were co-authors of the article, 'Sex pheromone receptor specificity in the European corn borer moth, Ostrinia nubilalis' in the journal 'PLoS ONE' which is contained within this thesis.; Kevin W. Wanner was a co-author of the article, 'Asian corn borer pheromone binding protein 3, a candidate for evolving specificity to the 12-tetradecenyl acetate sex pheromone' in the journal 'Insect biochemistry and molecular biology' which is contained within this thesis.
    The insect order Lepidoptera includes more than 180,000 species and some of the most well known pests of food and fiber crops. Ninety-eight percent of lepidopteran species belong to a taxonomic group called the Ditrysia. Modern Ditrysia use long distance sex pheromones to facilitate mating. The European corn borer, Ostrinia nubilalis (ECB) is a well known pest of agricultural crops throughout North America and Western Europe. The European corn borer species exists as two different pheromone races. Females of the species produce, and males are attracted to different blends of the isomers (Z)-11-tetradecenyl acetate and (E)-11-tetradecenyl acetate. The closely related Asian corn borer (O. furnacalis, ACB) has evolved to use a pheromone blend that is unique among all Lepidoptera, (Z)- and (E)-12-tetradecenyl acetate. O. nubilalis and O.furnacalis species can be used as models to study pheromone evolution. Pheromones are detected at the periphery of the olfactory system by olfactory sensilla located on the antennae. Proteins involved in pheromone detection at the periphery include: odorant receptors, pheromone binding proteins, and sensory neuron membrane proteins. In this study, the coding sequences of seven odorant receptors, five pheromone binding proteins, and two sensory neuron membrane proteins were cloned from Asian and European (E and Z race) corn borer antennae. Five odorant receptors and two pheromone binding proteins were expressed at high levels in male corn borer antennae based on quantitative real-time PCR assays. Several odorant receptors were heterologously expressed in Xenopus laevis oocytes, and odorant receptor 6 was found to respond specifically to (Z)-11-tetradecenyl acetate in electrophysiological studies. The coding sequences of all fourteen genes were analyzed by computational and statistical methods to identify candidate genes that may play a role in the detection of the ACB pheromone blend. Odorant receptor 3 and pheromone binding protein 3 may have evolved specificity to 12-tetradecenyl acetates. Future studies will clarify the role of these proteins in the evolution of pheromone detection at the molecular level. An improved understanding of the evolution of pheromone detection may lead to new pheromone based controls for these economically damaging species.
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