Download or read book Effects of Natural Gas Well Development on Songbird Reproductive Success in Mixed grass Prairies of Southeastern Alberta written by Jenny Yoo and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grassland songbird populations have experienced declines due to habitat loss. In Canada, gas well development continues to fragment and disturb prairie habitat. From 2010-2012, I monitored a total of 374 nests in mixed-grass prairie located in southeastern Alberta. I estimated the probabilities of nesting success relative to gas well infrastructure to test for effects on reproductive success. There was very little effect of well pads on nesting success, while roads had a greater impact. Savannah sparrow and chestnut-collared longspur clutch sizes and fledgling numbers per nest were lower near gas well pads and cattle water sources, suggesting lower quality habitat in these areas. Large-sized predators occurred less in areas with older well pads. Concentrations of new well pads may have greater effects on chestnut-collared longspur reproductive success. Minimizing habitat disturbance surrounding gas well pads, and reducing abundance of roads, should minimize impacts on reproductive success for most grassland songbirds.

Download or read book Breeding Biology of Grassland Songbirds and the Effects of Oil and Natural Gas Development on Their Density and Reproductive Success written by Sarah Maureen Ludlow and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Oil and Gas Development on Songbirds of the Mixed grass Prairie written by Jacy Bernath-Plaisted and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Oil Development on Habitat Quality and Its Perception by Mixed grass Prairie Songbirds written by Paulson G. Des Brisay and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oil development has altered mixed-grass prairies in south-eastern Alberta, potentially impacting habitat quality and suitability for grassland birds. I tested whether three passerines can accurately assess habitat quality in the presence of this anthropogenic disturbance. I monitored nesting success and stress hormones and tested for differences in settlement patterns at sites impacted by real oil infrastructure, simulated noise, and control sites. Corticosterone levels suggested that habitat quality was reduced in some cases by disturbance. I also found disturbance impacted perceived habitat quality; however, perceived and realized quality were not always affected similarly. Both Chestnut-collared Longspurs and Savannah Sparrows exhibited stress near infrastructure, but higher-quality Longspur females nested near infrastructure while Savannah Sparrows avoided it. This mismatch may help explain why species suffer disproportionately in response to disturbances. Managers should reduce human presence by concentrating above-ground infrastructure using directional drilling, decommissioning old well heads, reclaiming roads, and reducing traffic.

Download or read book The Effects of Natural Gas Development on Density Reproductive Success and Nest Survival of Grassland Songbirds in South Western Saskatchewan written by Carolyn Anne Gaudet and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Natural Gas Development and Grassland Songbird Abundance in Southwestern Saskatchewan written by Holly Jayne Kalyn Bogard and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Conventional Oil Wells and Associated Infrastructure on the Abundances of Five Grassland Songbird Species in Alberta s Mixed grass Prairie written by Heather R. Nenninger and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although grassland bird populations have steadily declined, little research has examined the effect of oil infrastructure on abundances of grassland songbirds. Even less research has identified mechanisms that explain observed effects. To evaluate this, I sampled abundance of 5 songbird species at oil well sites with different pump mechanisms, power sources, and activity levels; I also evaluated the effects of perch and road density and exotic vegetation, all of which are associated with oil development. Both Baird's sparrows (Ammodramus bairdii) and Sprague's pipits (Anthus spragueii) had lower abundances at all sites that contained oil infrastructure. The other 3 species, chestnut-collared longspurs (Calcarius ornatus), western meadowlarks (Sturnella neglecta), and Savannah sparrows (Passerculus sandwichensis), were relatively unaffected by oil wells, linear features, or exotic vegetation. Given that oil well sites negatively affected two species of concern, more research is needed to determine mitigation strategies.

Download or read book Landscape scale Effects of Oil and Gas Development on Grassland Passerines in Southern Alberta written by Jody Daniel and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Oil Infrastructure and Associated Noise on the Stress Physiology Growth and Development of an Altricial Grassland Songbird Nestling written by Alexandra L. Heathcote and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent decades, oil and gas development has increased in central North America, fragmenting grassland ecosystems and introducing anthropogenic noise to the soundscape. Chronic exposure to anthropogenic noise on the landscape may increase corticosterone levels in altricial songbird nestlings, potentially influencing growth rate, fledgling success, and adult behaviour. To determine how anthropogenic disturbance and chronic noise impacts the development of Chestnut-collared Longspur (Calcarius ornatus) nestlings, I isolated noise from the associated infrastructure by broadcasting generator-powered screwpump recordings on the short- and mixed- grass prairies of southeastern Alberta, and compared these impacts with those of real wells and controls. I measured basal corticosterone and stress response in nestlings and mothers as well as mass and outer primary length in nestlings as a metric for fitness. Surprisingly, I found nestlings closer to anthropogenic noise exhibited down-regulated HPA-axis activity as well as evidence to suggest that maternal stress mediated the relationship between noise and basal corticosterone. Mothers that responded strongly to novel stressors produced nestlings with longer primaries. In addition, across all sites nestlings with lower corticosterone were heavier. These results suggest that nestlings may benefit from living in noisy environments and that mothers may prepare their offspring for living in sub-optimal environments or growing up with sub-optimal care.

Download or read book Demographic Responses of Grassland Songbirds to Rangeland Management in the Tallgrass Prairie written by Bram Hendrik Ferdinand Verheijen and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Grasslands are among the most rapidly declining ecosystems in the world. The Flint Hills ecoregion contains one of the largest remaining tracts of tallgrass prairie, but most of the area is managed with high densities of grazing animals and frequent prescribed burns, thereby reducing variation in vegetative structure. A homogeneous landscape leads to lower diversity and abundance of wildlife species, including grassland songbirds. Patch-burn grazing management has been proposed to more closely match the historical interaction between fire and selective grazing by native ungulates. Pastures managed with patch-burn grazing have a greater variety of vegetative structure and plant species composition, and as a result, higher species diversity, abundance, and reproductive success of grassland birds. However, past work has not considered potential effects of regional variation in predation risk and rates of brood parasitism by Brown-headed Cowbirds (Molothrus ater), or annual variation in climatic conditions on the effects of patch-burn grazing management on the reproductive success of grassland songbirds. Over a six year period and at two tallgrass prairie sites, I tested the effects of patch-burn grazing on the reproductive success of three native grassland songbird species, Dickcissels (Spiza americana), Eastern Meadowlarks (Sturnella magna), and Grasshopper Sparrows (Ammodramus savannarum), as well as subsequent effects on the space use, movements, and survival of fledgling Dickcissels. I found only minor effects of patch-burn grazing on the reproductive success of grassland songbirds, supporting previous studies that show that patch-burn grazing does not have negative effects on demographic rates of grassland songbirds. Management regime did not affect densities or territory size of male Dickcissels, but bird densities tended to be higher and territories tended to be smaller on patches within the patch-burn grazing treatment that were burned in the previous year. Thus, patch-burn grazing management might benefit Dickcissel populations by providing higher quality breeding habitat in unburned patches. Last, I found evidence for a potential tradeoff between habitat selection for nests vs. fledglings of Dickcissels in some rangeland management strategies. Parents that realized high reproductive success by nesting in pastures with lower cowbird densities, produced fledglings that faced high rates of depredation by snakes and showed greater movements away from those pastures. Survival rates and movements of Dickcissel fledglings were low, especially during the first week after leaving the nest, which stresses the importance of local habitat conditions. At a larger spatial scale, I tested whether regional differences in habitat structure could drive variation in apparent survival of grassland songbirds. I found that grassland- and shrubland-breeding species had higher estimates of apparent survival than forest-breeding species, contrary to the prevailing viewpoint that birds breeding in dynamic landscapes, such as frequently burned grasslands, should show lower apparent survival than species that breed in woody habitats. The results of my field study show that restoring the historical interaction between fire and grazing on the landscape via patch-burn grazing management could benefit grassland songbirds. Moreover, my dissertation is the first study that tests the effects of patch-burn grazing management on the survival and movements of fledgling Dickcissels, and shows that high cowbird densities can cause a tradeoff between different life-stages. Future conservation efforts should take into account regional variation in species abundance, predator community composition and abundance of Brown-headed Cowbirds when assessing the effects of rangeland management on the demography of grassland songbirds.

Download or read book Indirect Effects of Wind Energy Development on Grassland Bird Habitat Use and Reproductive Success written by Anika Mahoney and published by . This book was released on 2015 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind energy development is rapidly expanding in grassland habitat, but potential indirect effects to wildlife populations are largely unknown. As observed in other types of human development, wind energy infrastructure could alter plant and invertebrate communities, change soil and hydrology, generate visual and aural noise, and increase human activity in previously undeveloped areas. These changes to habitat can indirectly affect wildlife in many ways, for example, by altering trophic interactions or habitat use. Native grasslands in the United States have undergone extensive habitat loss and degradation, and subsequently, many grassland-associated bird species have experienced precipitous population declines. We assessed the indirect effects of wind energy development on the habitat use and reproductive success of two grassland songbirds, Horned Lark (Eremophila alpestris) and McCown’s Longspur (Rhynchophanes mccownii) in Wyoming. We modeled bird density in 2012 as a function of habitat characteristics and wind energy development. We estimated bird density at two scales of development- between two wind farms and two undeveloped sites, and within wind farms as a function of proximity to nearest wind turbine. Despite a general characterization of Horned Larks as disturbance-tolerant, the numbers of Horned Lark within wind farms were substantially lower near turbines. McCown’s Longspur numbers were higher near turbines in areas with high heterogeneity in bare ground, but showed no variation with heterogeneity of bare ground far from turbines. These responses indicate potential avoidance of turbines by Horned Lark, and a difference in habitat associations by McCown’s Longspur near turbines. We evaluated nest placement of Horned Lark and McCown’s Longspur in 2012 in relation to turbine proximity on three wind farm plots. The mean turbine proximity at each plot was no different than predicted by a random distribution, and the turbine-proximity values of observed nests were uniformly distributed, indicating no evidence of displacement of nests from turbines. Although Horned Lark occur in lower numbers near turbines, there was no evidence of avoidance of turbines in nest placement. We assessed the reproductive success of Horned Lark and McCown’s Longspur in 2011 and 2012 on 3 wind farms and 2 undeveloped sites. We evaluated multiple indices of nesting productivity (clutch size, size-adjusted nestling mass, daily nest survival rate, and number of young fledged per successful nesting attempt), and modeled these reproductive metrics as a function of habitat and wind energy development. We quantified wind energy development using several measures of disturbance: turbine proximity, turbine density, distance to developed edge, and the amount of developed and reclaimed area within the neighborhood of the nest, and identified which measure was most predictive of reproductive success. Turbine density was repeatedly the measure of wind energy development most strongly associated with avian reproductive success. The nestling mass and, in 2011, nest survival of Horned Lark were negatively related to increasing turbine density. Annual variation in the effect of infrastructure on nest survival indicates that infrastructure may only have negative consequences in correlation with other biotic or abiotic events, e.g., during years of high predator abundance. The nest survival of McCown’s Longspur was most strongly predicted by nest site and neighborhood habitat variables and turbine density within 1 km of the nest. Likelihood of McCown’s Longspur nest survival decreased from 54% to 5% as vegetation density increased, and the inclusion of turbine density and grassland area in the neighborhood amplified this relationship resulting in a 28% to

Download or read book Effects of Marcellus Shale Development on Songbird Abundance and Habitat Use in Northcentral Pennsylvania Forests written by Ethan Barton and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to recent instability in the international petroleum products market, American industries are seeking to develop domestic sources of energy, and foremost among these domestic sources is natural gas. The Marcellus Shale formation in the northeastern portion of the United States contains a vast portion of the natural gas reserve of North America; the northeastern US also contains many large core forest reserves important for breeding songbirds. Within the last decade, development of wells within the Marcellus has rapidly expanded, and the number of wells permitted for drilling has increased steadily. In forested areas, Marcellus development creates large disturbances and causes substantial fragmentation, but the landscape matrix remains dominated by stands of mature forest. I examined the effects of Marcellus Shale gas development on songbird abundance and habitat use surrounding 30 well pads, mean size 2 hectares, placed within an extensive forest landscape in northcentral Pennsylvania. I used fixed-radius point counts to assess songbird abundance relative to well pads at four distances from the pad edge: two points in new edge habitat (0m and 50m) created by pad development and two points in remnant post-development interior habitat (150m and 250m), which served as a reference. I conducted bird and vegetation surveys in both northern hardwood and mixed oak habitat. To determine whether bird abundance and species composition differed between edge and reference points, I analyzed the aggregate avian community at edge and interior points and also built linear mixed models for three guilds of species based upon habitat preference: forest interior, early-successional, and synanthropic species. I also constructed linear mixed models for individual bird species within the guilds observed at >=50% of field sites. Avian communities differed between forest interior and pad edge, and they also differed by forest habitat type (northern hardwood or oak) overall and at interior reference points. However, communities did not differ by forest habitat type at edge points, indicating biotic homogenization may be occurring near well pads. Forest interior species were significantly less abundant near the pad edge relative to interior reference points. Interior habitat associates such as black-throated green warblers (Setophaga virens), black-throated blue warblers (Setophaga caerulescens), ovenbirds (Seiurus aurocapilla), red-eyed vireos (Vireo olivaceus), hermit thrushes (Catharus guttatus), and scarlet tanagers (Piranga olivacea) were less abundant at edge points than within the forest interior. In contrast, synanthropic species were more abundant near pad edges than at interior points. American robins (Turdus migratorius) were more abundant within 100m of well pad edges than at reference points within the forest interior surrounding well pads. Distance from edge was not a significant predictor of abundance for the early successional species guild or individual species associated with the guild. Common yellowthroats (Geothlypus trichas) and eastern towhees (Pipilo erythrophthalmus), two species associated with early successional habitat, did not exhibit a detectable response to development. I took nested-plot vegetation samples at points surrounding well sites to assess vegetative changes near well pads as a possible explanation for bird distribution. Average canopy cover, mean litter depth, the number of tree stems >8cm diameter at breast height, and the number of small sapling stems

Download or read book The Effects of Fire and Grazing on Breeding Birds in a Mixed grass Prairie written by Renae A. Schmitt and published by . This book was released on 2003 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Shallow Gas Development on Relative Abundances of Grassland Songbirds in a Mixed grass Prairie written by Jennifer Anne Rodgers and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mixed-grass prairie -- grassland songbirds.

Download or read book Effects of Oil Development on Grassland Songbirds and Their Avian Predators in Southeastern Saskatchewan written by Jason Howard Unruh and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The quantity and quality of Saskatchewan's remaining grassland may be threatened by energy development such as oil extraction. Grassland songbird populations are declining and increased oil development may be contributing to their declines through habitat loss and degradation. More quantitative research is needed to inform our understanding of how grassland songbirds are affected by oil development. I examined grassland songbird abundance, vegetation structure, habitat type (native and planted grasslands), and avian predator occurrence across a gradient of oil disturbance to determine the extent to which oil well proximity, density, and cumulative habitat disturbance influences the abundance of grassland songbirds and the occurrence of avian predators. I conducted 486 point counts in 243 sample sites (259 ha) at varying distances from oil wells, and in areas with varying well densities (0-48 wells/259 ha). The abundance of seven songbird species was reduced near oil wells or in areas with higher well densities, the abundance of two species was not influenced by oil wells, and the abundance of two species increased in the presence of oil wells or with greater well density. Three species also exhibited reduced abundance with greater cumulative disturbance, while two species exhibited reduced abundance when the area covered by well pads or oil access roads increased. I also found evidence that the abundance of four species was lowest in planted grassland compared to native grassland in the presence of oil development. My results indicate that oil development influenced vegetation structure, which likely influenced grassland songbird abundance to some degree. However, structural changes in vegetation did not account for all observed variation in songbird abundance. Finally, my results provide evidence that Northern Harrier occurrence is negatively influenced by oil development but that buteos and corvids are not affected. Northern Harrier occurrence is possibly influenced by habitat fragmentation caused by oil development since they are known to be area sensitive. As oil development increases in grassland habitat, its negative impacts on grassland songbirds will likely become more pronounced. Efforts should be made to limit well density and the cumulative area of disturbance on the landscape.

Download or read book Effects of Cattle Stocking Rate and Years Grazed on Songbird Nesting Success in the Northern Mixed grass Prairie written by Emily Pipher and published by . This book was released on 2012 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grazing -- Songbirds -- Nesting.

Download or read book The Effects of Timing of Mercury induced Developmental Stress on Songbird Reproductive Success written by Ohad Jonathan Paris and published by . This book was released on 2017 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis explored two questions – Does developmental exposure to methyl-mercury affect the later reproductive success of songbirds? Does the timing of such developmental exposure affect the severity of any effects on reproductive success? The second question was formulated to test the Developmental Stress Hypothesis (DSH), which states that early developmental conditions incur later-life fitness consequences. Methyl-mercury (MeHg), a potent environmental toxicant, may induce stress in developing organisms, and have far-reaching negative effects on adult fitness. I tested the DSH by investigating whether the timing of MeHg-induced stress, early vs. late in development, affected later-life reproductive success (a strong measure of fitness) in captive zebra finches (Taeniopygia guttata). Groups of siblings were divided across four treatments – early exposure (conception + 64 days), late exposure (beginning at 64 days post-conception + 64 days), complete exposure (conception + 128 days), and control (unexposed) – in order to account for genetic effects, and therefore have a rigorous test of the DSH. Birds were paired among families and within treatments once they reached adulthood. Key reproductive metrics were assessed, including the overall number of independent offspring produced per pair in an 8-month continuous breeding period (mean reproductive output). Among-treatment comparisons showed that late-exposed pairs outperformed early-exposed pairs to varying degrees, in all metrics, with a 21% higher, but not significantly different, reproductive output. Evidence in support of the DSH was therefore mixed, as performances were biologically different, but statistically indistinguishable. Mean differences suggest that the impact of stress on developing systems is greater earlier in development, and that phenotype, and therefore fitness, can be explained not only by genotype and environment, but also by the timing of stressful events. The first question was addressed by combining all performances of pairs in mercury-exposed treatments, and comparing these to controls. Control pairs outperformed developmentally-exposed pairs in all metrics but one, with large differences in the hatching success (40% higher in controls) and pair survival metrics (52% higher). The final mean reproductive output of control pairs was 80% higher than that of exposed pairs (5.58 vs. 3.11 offspring). Results were similar to ones recorded in studies of zebra finches exposed to MeHg during the reproductive process, highlighting the severe and irreversible harm MeHg-induced developmental stress can have on developing songbirds, and, more broadly, on songbird population stability. I therefore suggest that conservation and management strategies give priority to the remediation and/or protection against mercury pollution of breeding grounds and migration routes, in order to achieve the greatest impact.