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Factors influencing nest survival of white-tipped doves in the lower Rio Grande Valley, TexasGiese, Jordan Clarence 03 March 2017 (has links)
<p> The white-tipped dove (<i>Leptotila verreauxi</i>) is a sedentary, secretive columbid that ranges from Argentina to the Lower Rio Grande Valley (LRGV) of south Texas. Since its designation as a game species in 1984, little research has been dedicated to the species’ reproductive ecology. My objectives were to (1) identify predators of white-tipped dove eggs and nestling, (2) determine how the predator community differs among land cover types, (3) examine the impact of vegetation and landscape variation in both citrus and woodland land cover types on nest survival, (4) examine the impact of temporal variation on nest survival, (5) provide information on general nest ecology that is currently lacking, (6) investigate movements of doves and examine feasibility of tracking and recapture using a GPS/VHF transmitters pilot study. During the summers of 2015 and 2016, I conducted nest searches in citrus and woodland sites in Hidalgo County, Texas. I placed real-time, infrared emitting camera systems on a subset of nests to monitor predation. I also trapped, banded, and placed backpack transmitters on doves in Estero Llano Grande State Park (ELGSP) In the 2 years, I located 63 dove nests, 34 in citrus and 29 in woodland. I placed camera systems on 33 nests and identified 9 species of nest predator. Green jays (<i>Cyanocorax incas</i>) were our most common nest predator, accounting for 10 of 28 predation events. Other predators were crested caracara (<i>Caracara cheriway</i>), Harris’s hawk (<i>Parabuteo unicinctus</i>), great-tailed grackle (<i>Quisicalus mexicanus</i>), tawny crazy ant (<i> Nylanderia fulva</i>), rat (<i>Rattus</i> spp.), opossum (<i> Didelphis virginiana</i>), house cat (<i>Felis catus</i>), and Texas indigo snake (<i>Drymarchon melanurus erebennus</i>). Based on AIC candidate model selection, I identified nest stage as the best predictor of daily nest survival rate across both land cover types. By separating land covers for a second step to model selection, I identified different environmental variables as predictors of daily survival rate in each land cover type. In the woodland site, my null model was most important, indicating that no measured variables were important for predicting nest survival. In citrus, canopy cover was the top model. In citrus, a diverse predator community due to heavy human disturbance may have increased the importance of canopy cover and other concealment variables for nest survival. The different predator communities they encounter in the two land cover types that they nest in prioritize much different environmental conditions for nest survival.</p>
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The development and application of simulation models to aid in wildlife management decision-making /Cooper, Andrew B. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 98-104).
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The Trophic and Spatial Ecology of the Southern Flying Squirrel (Glaucomys volans) and Non-lethal Deterrent MethodsMeyer, Robert Timothy 18 May 2018 (has links)
<p> Southern flying squirrels (SFS; <i>Glaucomys volans</i>) are known kleptoparasites on the endangered red-cockaded woodpecker’s (RCW; <i> Picoides borealis</i>) cavities and cost land managers time and money to control, and the ecology of SFS in habitats managed for RCWs is poorly understood. This study is designed to obtain a better understanding of the general ecology of SFSs surrounding RCW habitat and provide possible non-lethal deterrent methods to prevent harmful interactions between SFSs and RCWs. Spatially-explicit capture-recapture showed generally higher SFS densities and habitat associations outside of RCW cluster partitions. Stable isotope analysis of SFS diets across Mississippi and Alabama revealed a narrow dietary breath relative to food items, thus habitat management may still be viable option to control SFSs. Lastly, investigation of odor deterrents resulted in the greatest avoidance of cavities containing gray rat snake (<i>Pantherophis spiloides </i>) feces and warrants further investigation.</p><p>
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Roosting, site fidelity, and food sources of urban gulls in massachusetts: Implications for protecting public water suppliesClark, Daniel E 01 January 2014 (has links)
Anyone who has spent time in coastal New England has seen gulls flying overhead and heard their familiar sound; gulls may be one of the most recognizable birds in the world. There are over 50 species of gulls worldwide, and many of them are closely associated with human development or activities. In Massachusetts, there are several common gull species including herring (Larus argentatus), great black-back (Larus marinus), laughing (Leucophaeus atricilla), and ring-billed (Larus delawarensis). While coastal encounters with gulls are ubiquitous, gulls can also be found inland, and ring-billed and herring gulls are now a common sight at lakes, parks, and commercial parking lots dozens or hundreds of kilometers from the ocean. This inland population of gulls presents unique challenges and exciting research opportunities. Because they are often closely associated with human activity, concentrations of inland gulls can lead to potential water quality concerns (when large roosts form on public water supply reservoirs), airplane hazards (when groups of gulls concentrate near airports or flight paths), or disease transmission (when gulls forage at landfills or waste water treatment plants then visit areas with people). In the following chapters I explore various aspects of inland gull ecology during the non-breeding season. In chapter 1, I review the concept of philopatry in birds and discuss ways to assess site faithful behavior. In Chapters 2 and 3, I explore some of the ecological aspects of inland gulls. Chapter 2 examines the site fidelity of gulls to their wintering areas and my results suggest that gulls exhibit high winter-site fidelity but variable site persistence during the winter season. Chapter 3 explores roost site selection throughout the year and models roost selection in Massachusetts. My results indicate that ring-billed gulls prefer freshwater roosts, while herring gulls use saltwater roosts more often. In Massachusetts, both herring and ring-billed gulls select inland freshwater roosts based on the size of the water body and proximity to their last daytime location. In Chapter 4, I detail the results of an experimental study trying to reduce the amount of anthropogenic food available to gulls at inland parking lots. Ring-billed gulls were the most common gull found in parking lots, and my educational approach to reduce feedings had mixed results; education seemed to reduce the number of feedings in some cases, but the number of gulls in each parking lot was not affected. In Chapters 5 and 6, I detail some applied management techniques. Chapter 5 discusses efforts to exclude gulls from a waste water treatment plant in central Massachusetts. Overhead stainless-steel wires were completely effective at preventing gulls from using structures at the treatment plant. Chapter 6 describes an innovative technique that was used to efficiently and effectively catch gulls during winter in highly urbanized environments. I captured over 1000 gulls using a net launcher in various parking lots and other urban areas.
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Impacts of Amur Honeysuckle (<i>Lonicera maackii</i>) Removal on the Composition ofAvian Assemblages in Rural Riparian ForestsDeJong, Leanna January 2020 (has links)
No description available.
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Movements and Habitat Relationships of Virginia Rails and Soras within Impounded Coastal Wetlands of Northwest OhioHengst, Nicole M. January 2021 (has links)
No description available.
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Impacts of Coyotes (Canis latrans) on White-tailed Deer (Odocoileus virginianus) Behavior and Mortality in the Chicago RegionAnchor, Gretchen 08 July 2019 (has links)
No description available.
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Laying the groundwork for public participation in cougar management : a case study of southwestern Oregon /Chinitz, Amy E. January 2002 (has links)
Thesis (M.C.R.P.)--University of Oregon, 2002. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 147-158).
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The politics of Mexican wildlife conservation, development, and the international system /Rose, Debra A. January 1993 (has links)
Thesis (Ph. D.)--University of Florida, 1993. / Vita. Includes bibliographical references (leaves 587-658).
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Comparing conventional and noninvasive monitoring techniques for assessing cougar population size in the southern Greater Yellowstone ecosystemAlexander, Peter D. 02 April 2016 (has links)
<p>Cougars (<i>Puma concolor</i>) are difficult to census due to their large home ranges, low densities, and cryptic nature. The conventional “gold-standard” method for estimating cougar abundance entails the capture and radio-tagging of individuals in a study area in an attempt to acquire a direct enumeration of animals in the population. While this method provides an accurate abundance estimate, it is logistically challenging and prohibitively expensive. Noninvasive survey techniques may offer the ability to both accurately and inexpensively monitor cougar populations. While noninvasive techniques have been used on cougar populations, there remain questions on their accuracy and comparative efficacy. We estimated the density of a cougar population in Northwest Wyoming using direct enumeration, and used this estimate as a reference with which to evaluate the accuracy and cost-effectiveness of three types of noninvasive surveys performed between 2010 and 2014. The noninvasive methods included two annual mark-recapture sessions of: 1) remote camera trapping, 2) winter hair-collection transects, and 3) scat detection dog surveys. </p><p> We GPS tracked 13 adult cougars (males = 5, females = 8) over 3 annual periods (Sep 2010–Sep 2013). We used proportional home range overlap to determine density in a 1,570 km<sup>2</sup> area. The average density was 0.82 cougars/100 km<sup>2</sup> (± 0.10 SD; n = 3 years). The remote camera surveys produced a mean density of 0.60 cougars/100 km<sup> 2</sup> (n = 2 years; relative SD = 56.5%). The scat detection dog surveys produced an average density of 2.41 cougars/100 km2 (n = 2 years; relative SD = 12.6%). The winter transects failed to produce a sample size large enough for an abundance estimate. Due to the inclusion of non-adults in the scat sampling, and the fact that the reference estimate was essentially a minimum count of adults, we believe that the scat-based estimate was more accurate than the lower estimate produced by remote cameras. Additional analysis indicated that individual identification of cougars in photographs may not be reliable, challenging the validity of photo-based abundance estimates of cougars. On a cost-per-detection basis, scat detection dogs were the most cost effective method (scat detection dogs = $341; remote cameras = $3,241; winter transects = $7,627). </p>
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