Theses and Dissertations at Montana State University (MSU)

Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733

Browse

Search Results

Now showing 1 - 10 of 26

Dynamics of native desert shrubs at restoration plots in the southern San Joaquin Valley, California
(Montana State University - Bozeman, College of Agriculture, 2019) Peppel, Landon Charles; Chairperson, Graduate Committee: Scott Powell
My study relied on data accumulated over multiple recent years for shrub restoration at Wind Wolves Preserve, a 37,635 ha nature preserve located in the Southern San Joaquin Valley, California. Shrub species selected for the restoration project focused on creating habitat for threatened and endangered species such as San Joaquin kit fox (Vulpes macrotis mutica), Western burrowing owl (Athene cunicularia hypugea), and blunt-nosed leopard lizard (Gambelia sila). Monitoring data from 541 individual plants across 8 different species and different height classes were examined for survival after the initial planting date. Analysis of variance (ANOVA) was used to compare the relationship to survival and individual shrub species and their heights at planting. Results indicate that certain shrub species survived more frequently than others (p < 0.0001). Plants also varied by height at the original planting date (p = 0.001); however, plant height did not significantly affect dead or alive status (p = 0.76). The results of this study have implications for management decisions for San Joaquin Valley shrub restoration on retired agricultural lands suitable for threatened and endangered species habitat restoration. Future studies might examine more closely the significance of planting date, and the use of other restoration techniques, such as inoculation of arbuscular mycorrhizal fungi.
Impacts of low-tech restoration methods on soil, vegetation, and livestock grazing in Montana's sagebrush steppe
(Montana State University - Bozeman, College of Agriculture, 2024) Lowing, Nicholas Allen; Chairperson, Graduate Committee: Bok Sowell
In the semi-arid rangelands of western North America, water is a limiting factor for plant growth. In Montana's high elevation rangelands, snowmelt is the primary source of water for ephemeral streams and mesic meadows. Wildlife and livestock rely on these areas especially when surrounding uplands have dried. Less snowpack and early melt times associated with climate change pose a threat to forage resources in this region. In 2018 and 2019, small rock restoration structures were constructed in seven drainages in southwest Montana with the intention of increasing resiliency in these systems. In this study we compare stream reaches with restoration structures to reaches without structures to assess the impacts of this technique on soil moisture, plant cover, diversity, evenness, and production. We observed cattle grazing within and adjacent to treated drainages to determine how they use the landscape. We used soil moisture probes to measure soil water content once per month in June-September of 2021 and 2022. We used 0.5m2 frames to estimate plant cover, diversity, and evenness June-September in both years. At the end of each growing season, vegetation frames were clipped and weighed to estimate production. Soil and vegetation sampling occurred in 54 reaches across 7 drainages. We observed cattle near four treated drainages in mornings and evenings to assess whether cattle prefer mesic or upland areas. Cattle observations occurred in July and August of 2021 and 2022. Using linear fixed effects models, we detected no differences (p > or = 0.05) in soil moisture between treated and untreated reaches during any sampling period. We detected no differences in vegetation cover, richness, diversity, or evenness in 92% of sampling periods. No differences in plant production were detected in 2021 or 2022. Cattle used mesic areas in greater proportion to their abundance on the landscape in both years (p < or = 0.0001). Our results indicate that these structures have not yet had major impacts on soil moisture or vegetation metrics. However, our results indicate that mesic meadows are an important resource for grazing cattle in southwest Montana's high- elevation rangelands, supporting the idea that these areas warrant restoration efforts.
Bee and butterfly communities in roadside habitats: identifying patterns, protecting monarchs, and informing management
(Montana State University - Bozeman, College of Letters & Science, 2023) Meinzen, Thomas Claasen; Chairperson, Graduate Committee: Diane M. Debinski
Insect pollinators play a critical role in our natural and agricultural ecosystems. With global pollinator declines and habitat loss, attention has turned to roadside right-of-way lands (ROWs) as potential areas for supporting pollinator populations. Although many roadsides host flowering plants, understanding whether--and under what circumstances--roadsides actually benefit pollinator populations is critical for good conservation decision-making. Through a literature review, we found that pollinator population data (e.g., birth and death rates) are lacking to assess whether roadsides are a source or sink for pollinator populations. However, conscientious management practices, including reduced, well-timed mowing, selective, targeted spraying, and well-placed native plantings can improve roadsides' potential to support robust pollinator populations. Identifying roadside habitat for diverse pollinator communities and imperiled species is essential to prioritize pollinator-focused management practices across ROW systems. To support efforts to conserve monarch butterflies (Danaus plexippus), we surveyed 1,465 km (910 miles) of southern Idaho highways, mapping 1,363 patches of showy milkweed (Asclepias speciosa), the monarch's host plant. Roadside milkweed often bordered irrigated fields and crops; water availability may best explain its distribution. Existing statewide milkweed models (Svancara et al., 2019) did not effectively predict milkweed distribution in ROWs, suggesting the importance of roadside-specific factors, such as ROW management and disturbance history. To identify patterns of pollinator richness and abundance in Idaho ROWs, we surveyed butterflies and sampled bees at a randomized set of 63 100-meter (328-foot) roadside transects in southeastern Idaho, stratified by highway class and NDVI (greenness) category. Lower NDVI (less green) sites, those with more flowering plant species, and sites along smaller, less-trafficked highways supported significantly more species of bees, while ROWs with more abundant flowers were associated with more species of butterflies. Low NDVI sites were often characterized by native sagebrush plant communities, while sites of high NDVI were associated with high proportions of non-native plants, suggesting that NDVI might be useful both in predicting bee richness and abundance (low values) and locating developing noxious weed patches (high values). These results, together with our management recommendations, can help prioritize ROWs for pollinator protection and increase their capacity to support diverse pollinator communities.
Ecological responses to meadow restoration in the sagebrush steppe of Montana
(Montana State University - Bozeman, College of Agriculture, 2023) Robison, Laura Margery; Chairperson, Graduate Committee: Bok Sowell
In the semi-arid landscapes of the Western United States, water is scarce. In the high-elevation sagebrush steppe of Southwest Montana, mesic meadows are primarily fed by melting snowpack. These meadows, often centered around an ephemeral stream, collect and store water in the soil. Between 60-80% of wildlife rely on meadows for resources when surrounding upland environments are dry. Warming temperatures and declining snowpack are threatening water resources in this region. Stream incision, often induced by historic land use, decreases water storage in surrounding meadows. In 2018 and 2019, rock restoration structures, typically less than 0.3 m tall, were installed in seven impaired catchments in Southwest Montana to mitigate climate change and incision by slowing and spreading water. Catchments spanned an ecological and abiotic gradient that accounts for over 1/3 of the variation within the sagebrush biome. We compared reaches with structures built to reaches without to assess the impact of restoration on average soil moisture, soil drying rate, water storage, water retention time after rainfall events, and sage-grouse chick food resources (plants and arthropods). We installed soil moisture probes at 24 reaches in 4 catchments, recording hourly measurements from June through September in 2020, 2021, and 2022. Using 0.5 m 2 frames, we estimated vegetation canopy cover at the species level once per month in June through September. We set 24 hr pitfall traps once per month from June through August. Vegetation and arthropod sampling occurred in 2021 and 2022 at 54 reaches in 7 catchments. We detected an increase in water residence time at treated reaches of 1.67 days (p=0.0069) after controlling for variation between catchments and reaches. We also found evidence for a 27% increase in total canopy cover (p=0.004) at treated reaches when compared to control reaches. We found no evidence of a difference in seasonal soil moisture, seasonal drying rate, seasonal water storage, arthropod activity density, or arthropod biomass. Our results indicate that rock restoration structures are effective in increasing soil moisture and vegetation components in mesic meadows in Southwest Montana, potentially providing a tool to restore meadows in semi-arid landscapes and build resilience against climate change.
Initial effects of low-tech restoration of wet meadows in sagebrush steppe
(Montana State University - Bozeman, College of Letters & Science, 2022) Sutton, Thomas Anderson; Chairperson, Graduate Committee: Andrea Litt; This is a manuscript style paper that includes co-authored chapters.
In semi-arid environments, wet meadows are important sources of late-season palatable vegetation for many wildlife species; these areas often support higher coverage and diversity of plants relative to surrounding upland environments. In the sagebrush steppe of southwest Montana, wet meadows are fed by melting snowpack. Due to climate change and land use practices, the duration and amount of moisture wet meadows receive is declining. To mitigate these changes, low-tech restoration structures, such as primitive rock dams, have been installed in six different drainages across southwest Montana. Similar structures have been studied in Colorado, where they found immediate increases in plant productivity. We used these structures within an experimental framework to compare soil moisture, vegetation structure, and vegetation composition (Chapter Two), as well as known food resources (both plants and arthropods) for sage grouse chicks and nesting sage thrashers, Brewer's sparrows, and vesper sparrows (Chapter Three) one and two years after restoration. We measured soil moisture and plant canopy coverage, as well as food resources for the focal birds during the summers of 2021 and 2022. We did not detect differences between treated and control areas in soil moisture, vegetation structure, or vegetation composition during any sampling period; however, many of our estimates for vegetation structure and composition were higher in treated than control areas two years after treatment. We also did not detect differences in plant or arthropod food resources for sage grouse chicks, nesting sage thrashers, or nesting Brewer's sparrows during any sampling period. We did find higher coverage of known plant foods for vesper sparrows in treated areas, compared to controls, during September, two years after treatment; this increase was mainly driven by Kentucky bluegrass. Given the cold climate of our study sites, more time may be needed before we can detect changes resulting from the restoration structures. Even if these low-tech solutions do not provide a 'cure-all' for wet meadow restoration, changes in climate and land-use practices emphasize the continued need to find effective and practical tools to restore wet meadows in arid landscapes.
Fish assemblage response to habitat restoration in Elk Springs Creek, Montana: implications for arctic grayling (Thymallus arcticus) restoration
(Montana State University - Bozeman, College of Letters & Science, 2021) Marsh, Jason William; Chairperson, Graduate Committee: Alexander V. Zale
The abundance and distribution of Arctic Grayling Thymallus arcticus in Montana have declined substantially during the past century as a result of habitat degradation and loss. Biologists tasked with conserving Arctic Grayling populations in the Centennial Valley of southwestern Montana implemented two habitat restoration projects to reclaim historical Arctic Grayling migration corridors and spawning habitats in Elk Springs Creek. I used before-after and before-after control-impact (BACI) study designs to evaluate the effects of these habitat restoration projects on physical habitat, water quality, and Arctic Grayling in Elk Springs and Picnic creeks. Because Arctic Grayling were rare in Elk Springs and Picnic creeks, I also examined the effects of restoration on two additional species (Brook Trout Salvelinus fontinalis and White Suckers Catostomus commersonii) with habitat requirements and life history characteristics similar to those of Arctic Grayling. I used electrofishing to monitor the abundance, biomass, and size distribution of each species before the restoration in 2016, and after the restoration during 2017 and 2018. A PIT-tag detection network monitored the seasonal movements of Arctic Grayling, Brook Trout, and White Suckers from spring 2016 through autumn 2018. In situ data loggers measured summer stream temperatures and dissolved oxygen concentration in expected fish migration corridors both before and after restoration. The abundances and biomasses of Arctic Grayling and White Suckers were similar before and after restoration. However, Brook Trout abundance and biomass increased significantly in the restored (impacted) reaches relative to the unrestored (control) reaches two years after habitat restoration. The size-class distributions of Arctic Grayling and Brook Trout broadened after restoration. Movements of Arctic Grayling, Brook Trout, and White Suckers among unique habitat segments in Elk Springs and Picnic creeks increased after restoration, but pre-restoration movement data was sparse and limited inference. Following channel restoration, summer stream temperatures decreased, and dissolved oxygen concentration increased and equilibrated. Physical habitat improved (i.e., fine sediments decreased, and depth, percentage of pools, and gravels increased) in restored historical Arctic Grayling spawning areas. I thereby showed that channel reconnection and spawning habitat restoration can substantially improve water quality and physical habitat. However, the restoration measures implemented in Elk Springs Creek affected my target species disproportionately.
Is habitat constraining bighorn sheep distribution and restoration: a case study in the Greater Yellowstone Ecosystem
(Montana State University - Bozeman, College of Letters & Science, 2019) Lula, Ethan Shawn; Chairperson, Graduate Committee: Robert A. Garrott
Rocky Mountain Bighorn Sheep (Ovis canadensis) restoration continues to be a challenge throughout western North America despite nearly a century of efforts dedicated to the species' recovery. A persistent problem for restoration is populations failing to expand into surrounding areas of habitat even during years of population growth. While populations can be constrained by several environmental factors and behavioral tendencies, we contend habitat availability is not the primary limiting factor. This study incorporated GPS data from bighorn sheep within the Taylor-Hilgard population in the Madison Mountain Range, located in the northwestern extent of the Greater Yellowstone Ecosystem (GYE), to develop summer and winter resource selection function (RSF) habitat models. The objective of this study was to evaluate a hypothesis that habitat was not the primary factor limiting distributions of bighorn sheep within the Madison Range by developing biologically-plausible RSF models and using covariates expected to influence selection. Multiple functional forms and spatial grains for covariates were considered and sets of summer and winter resource selection models compared using AIC subscript c. Results indicated that bighorn sheep resource selection was grain dependent, with bighorn sheep generally selecting covariates at the larger 500 m and 1,000 m spatial grains. Summer selection was characterized by rugged terrain, steep slopes, reduced canopy cover, southwestern aspects and ridgelines. Winter selection was characterized by low elevations, southwestern aspects, steep slopes, reduced canopy cover, ridgelines, high summer NDVI amplitude, and areas close to steep terrain (slopes > or = 45°). Predicted winter habitat occurred in a non-contiguous distribution primarily along low-elevation, southwest-facing aspects within the Madison Valley, and predicted summer habitat was concentrated along high elevation ridgelines. Model results were successfully validated using independent GPS data. Potential abundance for the Madison Range was estimated by linking the winter RSF to population estimates for the Taylor Hilgard and results suggested that the Range may be capable of supporting 2 to 4 times the number of bighorn sheep currently estimated. Study results supported the hypothesis that habitat was not the primary factor limiting extant bighorn sheep populations, suggesting that broader distributions within the Range are possible if novel restoration strategies are considered.
Understanding the biology, ecology, and integrated managment of Ventenata dubia
(Montana State University - Bozeman, College of Agriculture, 2019) Harvey, Audrey June; Chairperson, Graduate Committee: Jane M. Mangold; Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'The effects of elevated temperature and CO 2 concentration on seedling growth of Ventenata dubia and Bromus tectorum' submitted to the journal 'Western North American naturalist' which is contained within this thesis.; Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'Indaziflam provided up to three-years of control for Ventenata dubia in southwestern Montana' submitted to the journal 'Invasive plant science and management' which is contained within this thesis.; Stacy Davis, Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'Effect of seeding date of Pseudoroegneria spicata (bluebunch wheatgrass) on establishment and subsequent ability to resist invasion by Bromus tectorum (cheatgrass)' submitted to the journal 'Ecological restoration' which is contained within this thesis.
Ventenata dubia (Leers) Coss., common name ventenata or African wire grass, is a non-native winter annual grass of increasing concern in western Montana. In North American, V. dubia appeared in the early 1950s; since then it has successfully established in the northeastern and northwestern United States. It is known to invade areas previously inhabited by Bromus tectorum (cheatgrass) and Taeniatherum caput-medusae (medusahead). In the Intermountain Pacific Northwest, V. dubia has caused substantial ecological and economic impacts in perennial grass habitats. Varying disturbance regimes contribute to its rapid expansion over the last decade. Impending climate change threats have the potential to exacerbate the spread of this invasive species. Three independent studies were conducted to explore the biology, ecology, and integrated management of V. dubia populations in Montana to alleviate impacts by this species and other invasive annual grasses. A growth chamber study tested the effects of elevated carbon dioxide and temperature on seedling growth of V. dubia in response to climate change and in competition with B. tectorum. This competition replacement study indicated that at elevated climate conditions V. dubia and B. tectorum grow smaller and competition with V.dubia has the potential to decrease B. tectorum growth. A field-based herbicide efficacy trial utilizing the active ingredient indaziflam compared it to other commonly used herbicides to determine long-term control of V. dubia and potential plant community changes at 8, 11, 20, and 23 months after treatment. Foliar cover, species richness, and functional group biomass were collected. Findings indicated indaziflam can control V. dubia up to three years with positive implications for plant community dynamics. A revegetation study was used to determine the optimum seeding time for perennial grass species, Pseudoroegneria spicata, and the effects seeding time can have with competition dynamics with B. tectorum. A randomized complete block design was established and P. spicata grown for one season prior to Bromus tectorum seeding. After the second growing season, tillers and biomass were collected for both species. Findings indicated priority effects can occur with fall and early spring seeding of P. spicata, with implications for suppression of B. tectorum at earlier seeding dates.
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.
Restoring semi-arid lands with microtopography
(Montana State University - Bozeman, College of Agriculture, 2019) Dillard, Shannon Leigh; Chairperson, Graduate Committee: Anthony Hartshorn
Water is often limiting to plant establishment in semi-arid lands, and this limitation can be especially pronounced in restoration contexts where human legacy impacts and/or non-native plants are present. The application of herbicide and mulch can help retain soil moisture by killing unwanted plant species or lowering evaporative losses, respectively. Creation of microtopography, or soil surface variation, is a third technique that could alleviate growing-season water shortages. Here we report findings from a study that explored the effects of these three techniques combined with broadcast seeding a mix of four native grasses, one native shrub, and one native forb for increasing plant canopy cover and density at three sites in northern Yellowstone National Park. One year after treatment, plant cover in control plots averaged 60%. Across plots treated singly with 1.5% glyphosate herbicide, 3 cm of red cedar mulch, or hand-dug microtopography, only mulch and microtopography increased canopy cover relative to control plots, although the increase consisted mostly of non-native species (>97%). Herbicide, not surprisingly, decreased canopy cover, and that decrease also consisted mostly of non-native species. The herbicide treatment was the most effective in encouraging native species canopy cover and density while simultaneously reducing the same measures of non-native species. Microtopography treatments encouraged growth of all plants (native and non-native), particularly in the micro-lows, but for this to be an effective restoration strategy, non-native species must first be controlled. Although herbicide was quite effective at reducing non-native species populations, particularly at the Cinnabar site, spraying must be timed with the phenology of the existing non-native plant community. We learned that reducing competition with non-native plants does not necessarily encourage native plant growth, which may indicate that growing conditions need to be improved at this site before restoration can be successful. Taken together, our results suggest that soil amendments like microtopography and mulch may have beneficial restoration applications in semi-arid lands but may also show little benefit on a short time-scale in a highly disturbed system. Areas plagued by non-native species invasions and legacy agricultural and grazing impacts are likely to require careful planning of restoration approaches in order to claim long-term success.

Theses and Dissertations at Montana State University (MSU)

Browse

Filters

Settings

Sort By

Results per page

Search Results