Theses and Dissertations at Montana State University (MSU)
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Item Climate change at the air-water interface affects giant salmonfly (Pteronarcys californica) emergence timing and adult lifespan(Montana State University - Bozeman, College of Letters & Science, 2023) Roche, Alzada Lois; Chairperson, Graduate Committee: Lindsey K. AlbertsonAquatic invertebrates experience complex temperature regimes throughout their life history, especially during the vulnerable life stage transition from aquatic to terrestrial habitats. When climate warming interacts with snowmelt in high elevation systems, it creates a novel set of conditions in which spring water temperatures remain within a narrow range from year-to-year while summer water and air temperatures rise. Giant salmonflies (Pteronarcys californica) depend on spring water temperature cues to time their large, synchronous emergence in early summer, but it is unknown how variable temperatures after this springtime cue affect life-history traits. We experimentally tested how changes in temperature in the 6 weeks before and after emergence affect emergence timing, emergence success, and adult lifespans. We found that the timing of emergence was 2.8 days earlier with each degree of warming during the weeks preceding emergence. However, there was no evidence that emergence success was affected by higher water temperature within our test temperature range (13-23°C). In the terrestrial adult stage, adult lifespans were shortened by increased air temperatures, especially when water temperatures during the aquatic juvenile stage had also been increased. The predicted lifespan was almost five times longer at the coldest air and water temperature combination than at the warmest (28 vs. 6 days). The shortest lifespans observed (3 days) are not likely to prevent successful reproduction, given that salmonflies can mate and oviposit within days of emergence. Still, because salmonflies can oviposit repeatedly for up to 80% of their lifespan, shortened lifespans may reduce total egg production and thus fitness. Our results indicate that rising water and air temperatures will impact not only the life history of the insects, but also the organisms in the riparian zone that rely on salmonfly emergence by altering the timing, magnitude, and duration of the nutrients provided by these large-bodied aquatic insects.Item Survey of habitat and fish communities in segments of Cherry Creek, a proposed site for the re-introduction of westslope cutthroat trout(Montana State University - Bozeman, College of Letters & Science, 2001) Moran, Sean Spence-PatrickItem Natural selection in the field and the classroom(Montana State University - Bozeman, College of Letters & Science, 2012) Andrews, Tessa Marie; Chairperson, Graduate Committee: Steven Kalinowski; Bradley B. Shepard, Andrea R. Litt, Carter G. Kruse, Lee M. Nelson, Patrick Clancey, Alexander V. Zale, Mark L Taper, and Steven T. Kalinowski were co-authors of the article, 'Performance of cutthroat trout from five populations translocated as embryos into a fishless common habitat in Montana' in the journal 'Canadian journal of fisheries and aquatic sciences' which is contained within this thesis.; Bradley B. Shepard, Andrea R. Litt, Carter G. Kruse, Alexander V. Zale, and Steven T. Kalinowski were co-authors of the article, 'Juvenile dispersal among cutthroat trout introduced as embryos to vacant habitat' in the journal 'North American journal of fisheries management' which is contained within this thesis.; Mary J. Leonard, Clinton A. Colgrove, and Steven T. Kalinowski were co-authors of the article, 'Active learning not associated with student learning in a random sample of college biology courses' in the journal 'Cell biology education-life sciences education' which is contained within this thesis.; Steven T. Kalinowski and Mary J. Leonard were co-authors of the article, 'Are humans evolving? : a classroom discussion to change student misconceptions regarding natural selection' in the journal 'Evolution education and outreach' which is contained within this thesis.This dissertation examined natural selection in westslope cutthroat trout (Oncorhynchus clarkii lewisi) and undergraduate learning in the subject area natural selection. Translocation-moving individuals to a new habitat to establish, re-establish or supplement a population-is a crucial management strategy for cutthroat trout. One of the major questions managers face in a translocation is which population(s) should contribute individuals? Unfortunately, we often know little about the differences among potential contributing population. The goal of the first half of this dissertation was to look for differences in performance among individuals from five populations of westslope cutthroat trout. I assessed survival, growth, and condition (Chapter 2) and dispersal (Chapter 3) following the translocation of embryos from these five populations to six introduction sites in Cherry Creek. No differences existed among these populations in relative survival, growth, or condition at age 1 or 2. In contrast, statistically significant differences existed in dispersal distance among these populations. These differences were consistent across some, but not all, introduction locations. As our knowledge of evolutionary biology has continued to grow, so too has our knowledge of how students learn evolution. Students taught using active learning strategies can learn substantially more about complex scientific concepts than students taught using primarily lectures. The goal of the second half of this dissertation was to further examine how students learn natural selection and how instructors facilitate that learning. I conducted a national survey of the relationship between an instructor's use of active learning strategies and how much students learned about natural selection (Chapter 4). I used a random sample of instructors from the largest and most prestigious universities in the country so that my results could be inferred to this large population of instructors. The degree to which instructors used active learning was NOT associated with student learning in this population of typical biology instructors. However, I found that a discussion of contemporary human evolution that used active learning strategies could effectively facilitate student learning of natural selection (Chapter 5).Item Unintended consequences in restoration : investigating interactions between trout habitat enhancement and anglers in western streams(Montana State University - Bozeman, College of Agriculture, 2011) Black, Eva Jordanna; Chairperson, Graduate Committee: Geoffrey Poole.; Geoffrey C. Poole and Alexander Zale were co-authors of the article, 'Fish and angler use of instream habitat enhancement structures in 'restored' stream reaches' in the journal 'Fisheries' which is contained within this thesis.Previous research spanning lotic, lentic, and marine environments suggests that habitat enhancement structures (HES) may attract and concentrate fish from adjacent habitats rather than increase fish populations. In addition to concentrating fish, we hypothesized that anglers may target HES, and therefore, that fish concentrated at HES may be more susceptible to angling. To test our hypotheses, we assessed spatial patterns of: 1) habitat structure; 2) fish holding locations; and 3) fishing pressure (i.e., casting patterns) in southwestern Montana stream reaches with HES. Findings suggest that HES aggregate fish and that anglers more successfully target fish holding near artificial HES than similar densities of fish holding further from artificial structures (e.g., near natural holding structures). We conclude that installation of HES may increase angling opportunities, but could also act as fish population sinks by focusing fishing pressure over likely fish holding areas.