Theses and Dissertations at Montana State University (MSU)
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733
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Item Do spawning salmon indirectly influence ungulate space use in the Copper River Delta, Alaska by attracting bears?(Montana State University - Bozeman, College of Letters & Science, 2020) DeFries, Elizabeth Shaw; Chairperson, Graduate Committee: Greg FrancisOne of the key challenges in ecology is understanding the drivers of animal movements and distributions. Here, I used remote camera photography to examine whether the timing of spawning salmon altered ungulate space use due to the presence of bears. Using observational data collection methods, I quantified ungulate and bear presence at individual salmon spawning sites. I then analyzed relationships between bear and ungulate detection data to test for indirect effects between salmon and ungulates by applying linear regression models. A zero-inflated negative binomial model suggested that increases in bear detections are associated with decreases in ungulate detections. Results did reveal little overlap in the timing of ungulate and bear use of stream habitat during salmon spawning times, however, rigorous testing of my hypothesis may be limited by low rates of ungulate detection. Research dedicated to understanding the indirect effects of the timing of salmon spawning in the Copper River Delta can help evaluate the evidence for trophic interactions at various ecosystem levels. It may also offer insights into the potential magnitude the impact salmon has on the prey of large predators, other herbivore densities, plant communities, riparian area morphology, and essential ecosystem functions.Item The response of parafluvial soils to beaver mimicry restoration in a Montane stream(Montana State University - Bozeman, College of Agriculture, 2020) Whitehead, Briana Katherine; Chairperson, Graduate Committee: Tracy M. Sterling and William Kleindl (co-chair); Paul Stoy, William Kleindl, Martin Rabenhorst, Rob Payn, David Wood and Anthony Hartshorn were co-authors of the article, 'Parafluvial soil response to beaver mimicry restoration in a montane stream' submitted to the journal 'Restoration ecology' which is contained within this thesis.Beaver Mimicry Restoration (BMR) is a relatively new aquatic restoration practice that seeks to improve deteriorated stream ecological functions. BMR is designed to rejoin hydrologically disconnected streams with their adjacent floodplains via the installation of small-scale, stream-spanning structures derived from natural materials and inspired by the influence of natural beaver (Castor spp.) dams. These structures capture sediment, elevate stream stage and groundwater tables, create thermal refugia, and re-establish riparian vegetation. Most research on BMR has focused on the hydrological or botanical results, but little is known about the response of parafluvial soils. I report measurements of soil water content, soil temperature, soil biogeochemical reduction, and vegetation responses at paired BMR-influenced treatment and non-BMR-influenced control locations from June through September of 2018 and 2019 in a montane stream in southwestern Montana (USA). In comparison to soils at control sites, soils adjacent to BMR activity experienced an extended period of higher water contents (0.23 m 3/m 3 higher), increased anoxic conditions (on average 27% more during the field season), a less variable and cooler soil temperature range (on average 5 °C cooler), and supported longer durations of vegetation greenness (additional 20 days) during the dry months. Results demonstrate how BMR produces conducive conditions for the development of new and/or the reestablish of historic hydric soils.Item Wetlands and copper concentrations across a headwater catchment impacted by acid rock drainage(Montana State University - Bozeman, 2000) Novak, Tracy M. Knoop; Chairperson, Graduate Committee: Paul HookItem Relationship between intensity of livestock grazing and trout biomass in headwaters of east front Rocky Mountain streams, Montana(Montana State University - Bozeman, College of Letters & Science, 2016) Gilham, Andrew Terrence; Chairperson, Graduate Committee: Alexander V. ZaleLivestock grazing is the most common land-use practice in the western United States. Riparian and stream habitats are particularly susceptible to effects of poorly-managed livestock grazing. About 80% of stream and riparian habitats in the western United States are thought to have been damaged by livestock grazing, but because grazing usually pre-dated assessments of fish populations and stream habitats, before and after comparisons are impossible. The spatial and temporal complexity of livestock grazing make it difficult to isolate its effects on instream habitat and channel morphology characteristics. Moreover, instream habitat and channel morphology are also influenced by inherent watershed characteristics (i.e., basin area, gradient, discharge). I assessed the effects of livestock grazing on 25 separate 150-m long sample sites (1400 to 1585 m in elevation) within ten headwater basins along the northeastern Rocky Mountain Front in north-central Montana. I used scat counts as an index of relative grazing intensity to assess the effects of livestock grazing on channel morphology characteristics, stream substrate, instream cover, and trout biomass. To my knowledge, this effort is the first to quantify livestock grazing intensity using scat counts to assess grazing effects on trout biomass. I assessed potential effects that grazing intensity had on habitat condition and fish biomass using linear mixed models, which also accounted for watershed and sample site effects. I found that the proportion of fine sediment in the streambed increased as the number of scats increased (P < 0.001), but the area of undercut banks declined as scat counts increased (P < 0.001). Estimated trout biomass declined as number of scats increased, even when I accounted random effects of stream and year in a linear mixed-effect model (P = 0.009). My results corroborate previous findings that livestock grazing along stream channels may reduce trout biomass, but unlike previous studies I actually quantified grazing intensity using scat counts. Since increased livestock grazing intensities were related to increased levels of fine sediments in streambeds and smaller areas of undercut streambanks, I suggest that these factors may be related to why increased livestock grazing reduced trout biomass.Item Responses of fish assemblages to bank stabilization in a large river(Montana State University - Bozeman, College of Letters & Science, 2014) Reinhold, Ann Marie; Chairperson, Graduate Committee: Alexander V. Zale; Geoffrey C. Poole, Robert G. Bramblett, Alexander V. Zale and David W. Roberts were co-authors of the article, 'Cumulative effects of floodplain dikes and linear bank stabilization on Yellowstone River side channels' submitted to the journal 'Freshwater science' which is contained within this thesis.; Robert G. Bramblett, Alexander V. Zale, David W. Roberts and Geoffrey C. Poole were co-authors of the article, 'Use of side channels by a large-river fish assemblage' submitted to the journal 'Freshwater biology' which is contained within this thesis.; Robert G. Bramblett, Alexander V. Zale, Geoffrey C. Poole and David W. Roberts were co-authors of the article, 'Spatially-dependent responses of a large-river fish assemblage to bank stabilization and side channels' submitted to the journal 'Ecological applications' which is contained within this thesis.The Yellowstone River remains the longest unimpounded river in the conterminous United States. However, bank stabilization and floodplain dikes have altered its fish habitat. Therefore, I surveyed fish habitat and fish from Laurel to Sidney, Montana, to (1) quantify changes to side channels attributable to linear bank stabilization and floodplain dikes, (2) compare the habitat use of side channels to main channels by small fish during runoff and base flow, and (3) determine if bank stabilization and side channels influenced main-channel fish assemblages during base flow. Floodplain dike frequency, but not linear bank-stabilization extent, directly correlated to a net loss of side channels from the 1950s to 2001. However, side channels provided important fish habitat. Fish habitat use was similar between side and main channels during base flow, but not during runoff when catch rates in side channels were several times higher than in main channels and assemblage structure differed between side and main channels. Shallow, slow-current velocity (SSCV) habitats were slightly slower in side channels and SSCV patches were larger in side channels than in main channels during runoff, but not during base flow. These habitat differences partially explained the patterns in fish catch rates between channel types. During base flow, fish assemblages in main channels varied with bank-stabilization extent and side-channel availability in alluvial (unconfined) and bluff (confined) river bends. Bank stabilization and side channels had different and sometimes opposite influences on fish assemblage structure. Influences of bank stabilization and side channels on fish relative abundances varied depending on species and river bend geomorphology. Assemblage responses to side channels were more consistent and widespread than to bank stabilization, and more fish species associated with side channels than bank stabilization. Physical differences probably contributed to the assemblage differences between reference and stabilized river bends; stabilized alluvial pools were deeper than reference alluvial pools. The strengths of the relationships among fish assemblages, bank stabilization, and side channels were spatial scale-dependent; optimum scales ranged from less than 200 m to 3,200 m up- and down-stream, suggesting that bank stabilization and side channels influenced fish across multiple spatial scales.Item An examination of channel geomorphology, hydraulic characteristics, and fish habitat in Cottonwood Creek on the Montana University System's Bandy Ranch(Montana State University - Bozeman, College of Engineering, 2003) Hallock, Stephanie Ann; Chairperson, Graduate Committee: Joel CahoonItem Soil retention capability of Deschampsia caespitosa, Phalaris arundinacea, and Poa pratensis upon exposure to flowing water(Montana State University - Bozeman, College of Agriculture, 1992) Strobel, Curt Calvin; Co-chairs, Graduate Committee: Clayton Blayne Marlow and Frank F. MunshowerItem A comparison of water table dynamics and soil texture under black cottonwood recent alluvial bar, beaked sedge, and Geyser's/Drummond's willow communities(Montana State University - Bozeman, College of Agriculture, 1999) Law, Darin JayItem Evaluating riparian grazing guidelines on the Long Creek Allotment, Beaverhead National Forest(Montana State University - Bozeman, College of Agriculture, 1996) Rhodes, Burk JayItem Restoring Russian knapweed-infested riparian areas(Montana State University - Bozeman, College of Agriculture, 2003) Laufenberg, Stephen Michael; Chairperson, Graduate Committee: Roger L. Sheley.
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