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Effects of Aquaculture Decline on Spatial Distributions of Piscivorous BirdsRhodes, Ciera A 04 May 2018 (has links)
The effects of aquaculture decline on piscivorous birds in the Mississippi Delta concern catfish farmers with possible increases in fish loss and disease transmission. My study was aimed to (1) develop a new harassment method using unmanned aerial vehicles (UAVs) to effectively control piscivorous birds at fish farms; (2) determine change in spatial distribution of American white pelicans (Pelecanus erythrorhynchos) in the Mississippi Delta since aquaculture decline; and (3) determine third-order habitat selection by the pelicans in the wintering grounds. The UAV harassment did not reduce piscivorous bird abundance more than human harassment in a 2-year field experiment. Aerial surveys demonstrate that the pelicans used natural water bodies to find food more frequently in 2015–2017 than in 1997–1999. Average pelican flock size decreased following the aquaculture decline. Lastly, land cover and land use did not predict fine-scale habitat selection by the pelican.
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The Saguwentje of Berg En DalVeres, Michael J. 27 November 2012 (has links)
No description available.
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Multi-scale patterns of habitat use by Roanoke logperch (Percina rex) in Virginia rivers: a comparison among populations and life stagesRosenberger, Amanda Elizabeth 27 January 2003 (has links)
The Roanoke logperch (Percina rex) is a federally endangered large darter that occurs only within the Roanoke and Chowan drainages of Virginia. This dissertation examines multi-scale habitat use patterns by logperch in three river systems in Virginia, including comparisons among rivers and life stages.
The first study in this dissertation compares microhabitat use patterns of logperch among the Roanoke, Pigg, and Nottoway rivers. My objectives are to: 1) compare available microhabitat and microhabitat use by logperch among these rivers; and 2) examine the transfer of habitat models among rivers. Habitat availability in the three rivers indicates that the Nottoway River is least impacted by human activity, while the Pigg River is most impacted. The Roanoke and Pigg rivers are found within the same region of Virginia and share many habitat characteristics. Logperch consistently use silt free, loosely embedded gravel in all rivers and can occupy a variety of depths and velocities to accommodate substrate requirements. Microhabitat models transfer better between the similar Pigg and Roanoke rivers.
The second study in this dissertation compares micro- and meso-habitat use patterns by Roanoke logperch in the Roanoke and Nottoway rivers. My objectives are to: 1) compare micro- and meso-habitat use patterns of logperch in the Roanoke and Nottoway rivers; and 2) examine transfer of habitat models at both scales. An increase in scale from micro- to meso- habitat did not improve model transfer. Habitat selectivity and transfer was strongest at the microhabitat scale. Logperch appear to be microhabitat substrate specialists and mesohabitat generalists.
The final study in this dissertation examines ontogenetic patterns of habitat use by Roanoke logperch in the Roanoke and Nottoway rivers. My goals are to: 1) examine habitat use by three age classes of logperch and 2) compare ontogenetic patterns of habitat use between the Roanoke and Nottoway rivers. In the Roanoke River, adult and subadult logperch primarily used run and riffle habitat, often over gravel substrate. Subadults were found in lower water velocities and more embedded microhabitats than adults. Young-of-year logperch were found in shallow, stagnant backwaters and secondary channels. In the Nottoway River, both adult and subadult logperch were found over sand and gravel in deep, low velocity pools and runs. Subadults were observed in slightly more silted, lower velocity habitat. Younger age classes of logperch appear to be more vulnerable to sedimentation caused by human activity.
Evidence in this dissertation strongly indicates that logperch have strict substrate requirements and the distribution of habitat types and pathways of dispersal will be critical for completion of the logperch life cycle. A watershed-level conservation approach that addresses sediment loading and preserves ecological processes that provide ephemeral, seasonal, and persistent types of habitat required over logperch ontogeny will be most effective for management geared towards the recovery of this endangered species. / Ph. D.
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Black bears in Canyon de Chelly National Monument: Life in a changing environmentTredick, Catherine Anne 18 August 2011 (has links)
Understanding how wildlife utilize habitat at varying scales is important for understanding and predicting potential impacts of landscape changes (e.g., habitat loss and fragmentation, restoration efforts, climate change, etc.) and in determining effective strategies for conservation and management. This research examines fine-scale and landscape-level habitat use of black bears in Canyon de Chelly National Monument (CACH), Arizona, USA in the context of large-scale landscape change. Currently, CACH is undergoing a large-scale restoration effort to remove all of the non-native Russian olive (Elaeagnus angustifolia) and tamarisk (Tamarix ramosissima and T. chinensis) within the monument. As black bears rely on the Russian olive as a primary food source, a major goal of this research was to evaluate how bears currently use this resource and how its removal might affect bear habitat use and bear-human interactions within the monument.
I developed a model of 3rd order (fine-scale) black bear habitat use in CACH using an occupancy modeling approach. Model results indicated that fine-scale habitat selection by bears in CACH is being driven by the presence of non-native Russian olive as well as native food sources. Thus availability of native foods may be sufficient to maintain the bear population in CACH, and bears may quickly adapt to the loss of the non-native food source. Similarly, results showed that bears avoid human areas and farmsteads and prefer higher elevations, suggesting that once olive is removed in the lower canyons near human areas, bear-human interactions may become less of a problem over the long term.
I also developed a model of 2nd order (landscape-level) habitat use and evaluated movement patterns of black bears in CACH using location data collected from GPS collars. Model results showed that bears selected areas with higher tree canopy cover and terrain ruggedness, indicating that forest cover and escape cover are primary factors driving black bear habitat selection at the landscape scale in this region. Movement patterns revealed large mean daily movements and low average turning angles, indicating long, linear movements designed to take advantage of the mosaic of available habitats and food resources available over larger areas.
I extracted DNA from hair samples collected throughout the study area to examine genetic variability and population structure of black bears in the region. Analyses revealed a relatively healthy, panmictic population across the wider landscape. No substantial genetic structuring was observed in multiple analyses, though I did find evidence of a slight isolation-by-distance pattern within the population. Measures of both current (Nb = 24) and long-term (Ne = 579) effective population size indicated a relatively high number of breeders in the current population and a sufficient amount of gene flow within the larger "superpopulation" to maintain long-term genetic viability.
I focused the final portion of my dissertation research on understanding the factors that influence stakeholder acceptance capacity for black bears, which plays a central role in contemporary wildlife management issues, including human-wildlife conflict. I used data from telephone interviews of 1,546 residents in Virginia to develop conceptual models of black bear acceptance capacity at both county and state levels. Model results suggested that more deep-seated and less easily influenced factors (e.g., values and risk perceptions) are at the heart of stakeholder attitudes and perceptions of wildlife, making influencing these perceptions more difficult. Agencies can indirectly affect these attitudes and perceptions, however, by targeting more potentially pliable factors related to wildlife acceptance capacity such as knowledge, personal experience with wildlife, and trust in management agencies. / Ph. D.
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Determining Habitat Associations of Virginia and Carolina Northern Flying Squirrels in the Appalachian Mountains from Bioacoustic and Telemetry SurveysDiggins, Corinne Ashley 23 August 2016 (has links)
The Virginia northern flying squirrel (Glaucomys sabrinus fuscus) and the Carolina northern flying squirrel (G. s. coloratus) are geographically isolated subspecies of the northern flying squirrel found in montane conifer-northern hardwood forests the Appalachian Mountains of the eastern United States. Both subspecies were listed under the Endangered Species Act in 1985 as endangered, and accordingly, the Virginia northern flying squirrel and the Carolina northern flying squirrel are considered high conservation priorities by state and federal agencies. Although the listing prompted work to determine the broad distribution and habitat associations of both subspecies, numerous data gaps remain, particularly with regard to habitat management and development of efficient monitoring techniques. Regional interest in restoration of red spruce (Picea rubens) forests in the central and southern Appalachian Mountains, considered to be the flying squirrels' primary habitat, increases the importance of understanding habitat selection and managers' ability to detect squirrels at multiple spatial and temporal scales.
I compared two novel survey techniques (ultrasonic acoustics and camera trapping) to a traditional technique (live trapping) to determine which method had higher probability of detection (POD) and lower latency to detection (LTD, number of survey nights to initial detection) of northern flying squirrels in the region. Both novel techniques performed better than the traditional techniques with higher POD and lower LTD. I found that ultrasonic acoustics and camera trapping had similar POD, whereas LTD was significantly lower with ultrasonic acoustics versus camera trapping. Additionally, the ability to distinguish between northern flying squirrels and the parapatric southern flying squirrel (G. volans) also is possible with ultrasonic acoustics, but not with camera trapping. This ultimately makes ultrasonic acoustics the most effective and efficient method to obtain detection/non-detection data. To better inform management decisions and activities (i.e., red spruce restoration), this method should be used in conjunction with existing traditional monitoring techniques that provide demographic data such as nest boxes.
I assessed habitat selection of radio-collared Virginia and Carolina northern flying squirrels at multiple spatial scales with use-availability techniques. I analyzed field data from paired telemetry and random points and determined Virginia northern flying squirrels microhabitat (within-stand habitat) selection showed preference for conifer-dominant stands with deep organic horizons, a factor that might be directly linked to food (hypogeal fungi) availability.
Similar to previous studies on the Virginia northern flying squirrel on the landscape- and stand-level using Euclidean distance based analysis, Carolina northern flying squirrels also selectively preferred montane conifer forests in greater proportion than their availability on the landscape. Additionally, Carolina northern flying squirrels did not select for or against northern hardwood forests regardless of availability on the landscape. Habitat preference of both subspecies indicates that red spruce restoration activities may be important for the persistence of Appalachian northern flying squirrels into an uncertain future, as anthropogenic climate change may cause further reduction of the quality and extent of high-elevation montane conifer forests in the region. / Ph. D.
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Quantifying patterns and select correlates of the spatially and temporally explicit distribution of a fish predator (Blue Catfish, Ictalurus furcatus) throughout a large reservoir ecosystemPeterson, Zachary James January 1900 (has links)
Master of Science / Division of Biology / Martha E. Mather / Understanding how and why fish distribution is related to specific habitat characteristics underlies many ecological patterns and is crucial for effective research and management. Blue Catfish, Ictalurus furcatus, are an important concern for many fisheries agencies; however, lack of information about their distribution and habitat use remains a hindrance to proper management. Here, over all time periods and across months, I quantified Blue Catfish distribution and environmental correlates of distribution in Milford Reservoir, the largest reservoir in Kansas. I tested relationships among acoustically tagged Blue Catfish and three groups of variables postulated to influence Blue Catfish distribution in the literature (i. localized microhabitat variables, ii. larger-scale mesohabitat variables, iii. biotic variables). Blue Catfish were consistently aggregated in two locations of the reservoir across five months during summer and fall, 2013. Using multiple linear regression and an information theoretic model selection approach, consistent correlates of distribution included localized, microhabitat variables (i.e., dissolved oxygen, slope) larger-scale, mesohabitat variables (i.e., distance to channel, river kilometer from the dam) and a biotic variable (i.e., Secchi depth). This research identified which 5 of the 12 variables identified in the literature were most influential in determining Blue Catfish distribution. As a guide for future hypothesis generation and research, I propose that Blue Catfish distribution was driven by three ecologically-relevant tiers of influence. First, Blue Catfish avoided extremely low dissolved oxygen concentrations that cause physiological stress. Second, Blue Catfish aggregated near the channel, an area of bathymetric heterogeneity that may offer a foraging advantage. Third, Blue Catfish aggregated near low Secchi depths, shown here to be associated with increased productivity and prey abundance. Building on my results, future research into the distribution and habitat use of Blue Catfish should incorporate aggregated distributions of fish into research designs, focus on how both small and large scale relationships interact to produce patterns of distribution, and explore further the mechanisms, consequences, and interactions among the three tiers of influence identified here.
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Frogs about town : aspects of the ecology and conservation of frogs in urban habitats of South Africa / David Johannes Donnavan KrugerKruger, David Johannes Donnavan January 2014 (has links)
Globally urbanisation impacts on 88% of amphibian species and is recognised as a major cause for the observed amphibian declines. This is as result of habitat fragmentation, alteration in habitat morphology and degradation of habitat quality. The interference of anthropogenic noise on anuran communication and the impacts thereof on their breeding success has become a major research focus in recent conservation studies. . However, within the African continent very little research has been conducted on the effects of urbanisation on anuran habitat and the acoustic environment, which is the main focus of this study. The thesis is structured as follows:
CHAPTER ONE provides an introduction to the field of urban ecology and relates it to amphibian conservation. The chapter reviews the far reaching and diverse effects of urbanisation on frog populations reported in literature across the world and also supply a broad introduction to the succeeding chapters. It also briefly summarises evidence from literature on the positive contributions brought about by the developed world. Following the vast negative impacts of urbanisation, the importance of amphibians is briefly discussed to motivate their conservation in urban environments, before concluding with a motivation for the need for urban ecological research on amphibians in South Africa.
CHAPTER TWO addresses the distribution of amphibian communities across an urban-rural gradient in the city of Potchefstroom and assesses the habitat determinants explaining distribution at both local (pond) and landscape scales. Four surveys conducted spanned the breeding seasons of all species occurring in this region and included three different sampling techniques to detect fish and anuran larvae species. Seven micro-habitat and seven landscape variables were included to evaluate determinants of habitat use among local species and species richness. Using Bayesian modelling, aquatic vegetation, predatory fish and pond size was found to be major determinants shaping species richness on a local scale, whereas surface area of urban central business district had only a slightly negative correlation with species richness on a landscape scale. This is a pioneer study for documenting effects of urbanisation on amphibian communities along an urban-rural gradient in Africa.
CHAPTER THREE evaluates the extent of the influence of aircraft acoustic noise on the calling behaviour of the critically endangered Pickersgill’s Reed Frog, Hyperolius pickersgilli. Literature documenting the effects of airplane noise on anuran calling activity is very limited and this study aimed not only to contribute to existing knowledge, but also to provide the first study of its kind within South Africa. Effects on five call properties of H. pickersgilli were determined
using passive and directional recording equipment at two sites, reflecting presence and absence of aircraft flybys. Results showed an increase in calling rate of H. pickersgilli during aircraft flybys. Hyperolius pickersgilli was found to call throughout the night until just before sunrise. The calling behaviour, frequency structure and call sound pressure level of H. pickersgilli suggest that this species is prone to be effected by continuous anthropogenic noise. However, the lack of flights between midnight and sunrise provides a period of no disturbance for the frogs. Future studies on the effects of change in calling behaviour should be supported by playback studies at quiet sites and connected to breeding success to determine if these effects are detrimental to the survival of this critically endangered species.
CHAPTER FOUR focussed on the Western Leopard Toad, Amietophrynus pantherinus and was divided into two major parts. One component focussed on the migration of this species across roads and aimed to firstly quantify the number of individuals migrating over a 500 m stretch of road using a drift fence system operated by public volunteers. The drift fence proved very successful, with no roadkill observed during the time it was in place. This study also stressed that large numbers of toads (average of 20.47% of 2 384 toads over six breeding seasons) are still being killed on the urban and suburban roads. Road patrol statistics collected by volunteers are biased in the sense that it is prone to human error, but when a drift fence is constructed, bias is excluded and space for human error limited. The study also provided road sensitivity areas analysed using geographic information systems to create digital buffer zones of 250 m, 500 m and 1 000 m around selected breeding sites.
Secondly the study aimed to evaluate the use of data collected by these citizens occupying a volunteering role in the toad’s conservation. The second part of this study was directed towards the acoustic analysis of the call of A. pantherinus. The two main objectives of this component were to 1) evaluate the extent of variation of the call properties in order to 2) assess whether the ambient anthropogenic noise have an effect on these properties. Seven call properties for advertisement calls and four for release calls were analysed. Call properties were found to vary significantly between populations (P<0.05). Although sound pressure level was found to have an effect on variation by using canonical redundancy analysis, variation can also be explained by the geographical isolation of the populations.
CHAPTER FIVE provided novel data on the extensive repertoire of Amietia quecketti in terms of its unique calling behaviour. Directional recordings were used to examine the extent of the variation in the two-part call (click-note followed by a whine-note). The whine-note was re-described and four different notes were designated, including the tonal-note, creak-note,
pulsatile- / rip-note, and whine-note. Furthermore, the newly assigned whine-note was divided into nine phases that differed in frequency structure. Also, evidence is provided that A. quecketti males call at high frequencies. The success of A. quecketti in urban environments as observed in Chapter 2 is described in terms of this species’ extensive repertoire and unusual frequency structure.
CHAPTER SIX provides insight into the effects of atmospheric conditions on the calling behaviour of Amietia quecketti, giving the proximate impact urbanisation has on weather conditions as well as the potential impact human activities can have on climate change on the long term. Calling activity was monitored over a nine-week period together with data from a mobile weather station which logged atmospheric variables every five minutes. Amietia quecketti was found to call most intensely between 00h00 and 03h00 in the morning and was most active in May, June and August. Humidity, temperature and wind velocity were found to have significant effects (P<0.05) on the calling activity of A. quecketti.
CHAPTER SEVEN is concerned with the attitudes of people towards frogs in South Africa. The first part of this study assessed the attitudes of people towards frogs in Potchefstroom. Surveys were distributed via the internet as well as manually to reach people with no internet access as well. Attitudes of people of Potchefstroom were mostly positive with more than half of the sampled population of 295 respondents indicating a strong liking in frogs. This study provides evidence that the presence of myths and knowledge can highly affects people’s attitudes towards frogs. The second part of this study focussed on the motivations of volunteers saving Western Leopard Toads from roadkill in Cape Town, South Africa. Volunteers were motivated by a strong value-driven approach to saving toads.
CHAPTER EIGHT provides a general discussion and outline on the contributions this study presented and also the new areas where more research is needed within the extent of the field of urban ecology from a South African perspective. / hD (Zoology), North-West University, Potchefstroom Campus, 2014
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Frogs about town : aspects of the ecology and conservation of frogs in urban habitats of South Africa / David Johannes Donnavan KrugerKruger, David Johannes Donnavan January 2014 (has links)
Globally urbanisation impacts on 88% of amphibian species and is recognised as a major cause for the observed amphibian declines. This is as result of habitat fragmentation, alteration in habitat morphology and degradation of habitat quality. The interference of anthropogenic noise on anuran communication and the impacts thereof on their breeding success has become a major research focus in recent conservation studies. . However, within the African continent very little research has been conducted on the effects of urbanisation on anuran habitat and the acoustic environment, which is the main focus of this study. The thesis is structured as follows:
CHAPTER ONE provides an introduction to the field of urban ecology and relates it to amphibian conservation. The chapter reviews the far reaching and diverse effects of urbanisation on frog populations reported in literature across the world and also supply a broad introduction to the succeeding chapters. It also briefly summarises evidence from literature on the positive contributions brought about by the developed world. Following the vast negative impacts of urbanisation, the importance of amphibians is briefly discussed to motivate their conservation in urban environments, before concluding with a motivation for the need for urban ecological research on amphibians in South Africa.
CHAPTER TWO addresses the distribution of amphibian communities across an urban-rural gradient in the city of Potchefstroom and assesses the habitat determinants explaining distribution at both local (pond) and landscape scales. Four surveys conducted spanned the breeding seasons of all species occurring in this region and included three different sampling techniques to detect fish and anuran larvae species. Seven micro-habitat and seven landscape variables were included to evaluate determinants of habitat use among local species and species richness. Using Bayesian modelling, aquatic vegetation, predatory fish and pond size was found to be major determinants shaping species richness on a local scale, whereas surface area of urban central business district had only a slightly negative correlation with species richness on a landscape scale. This is a pioneer study for documenting effects of urbanisation on amphibian communities along an urban-rural gradient in Africa.
CHAPTER THREE evaluates the extent of the influence of aircraft acoustic noise on the calling behaviour of the critically endangered Pickersgill’s Reed Frog, Hyperolius pickersgilli. Literature documenting the effects of airplane noise on anuran calling activity is very limited and this study aimed not only to contribute to existing knowledge, but also to provide the first study of its kind within South Africa. Effects on five call properties of H. pickersgilli were determined
using passive and directional recording equipment at two sites, reflecting presence and absence of aircraft flybys. Results showed an increase in calling rate of H. pickersgilli during aircraft flybys. Hyperolius pickersgilli was found to call throughout the night until just before sunrise. The calling behaviour, frequency structure and call sound pressure level of H. pickersgilli suggest that this species is prone to be effected by continuous anthropogenic noise. However, the lack of flights between midnight and sunrise provides a period of no disturbance for the frogs. Future studies on the effects of change in calling behaviour should be supported by playback studies at quiet sites and connected to breeding success to determine if these effects are detrimental to the survival of this critically endangered species.
CHAPTER FOUR focussed on the Western Leopard Toad, Amietophrynus pantherinus and was divided into two major parts. One component focussed on the migration of this species across roads and aimed to firstly quantify the number of individuals migrating over a 500 m stretch of road using a drift fence system operated by public volunteers. The drift fence proved very successful, with no roadkill observed during the time it was in place. This study also stressed that large numbers of toads (average of 20.47% of 2 384 toads over six breeding seasons) are still being killed on the urban and suburban roads. Road patrol statistics collected by volunteers are biased in the sense that it is prone to human error, but when a drift fence is constructed, bias is excluded and space for human error limited. The study also provided road sensitivity areas analysed using geographic information systems to create digital buffer zones of 250 m, 500 m and 1 000 m around selected breeding sites.
Secondly the study aimed to evaluate the use of data collected by these citizens occupying a volunteering role in the toad’s conservation. The second part of this study was directed towards the acoustic analysis of the call of A. pantherinus. The two main objectives of this component were to 1) evaluate the extent of variation of the call properties in order to 2) assess whether the ambient anthropogenic noise have an effect on these properties. Seven call properties for advertisement calls and four for release calls were analysed. Call properties were found to vary significantly between populations (P<0.05). Although sound pressure level was found to have an effect on variation by using canonical redundancy analysis, variation can also be explained by the geographical isolation of the populations.
CHAPTER FIVE provided novel data on the extensive repertoire of Amietia quecketti in terms of its unique calling behaviour. Directional recordings were used to examine the extent of the variation in the two-part call (click-note followed by a whine-note). The whine-note was re-described and four different notes were designated, including the tonal-note, creak-note,
pulsatile- / rip-note, and whine-note. Furthermore, the newly assigned whine-note was divided into nine phases that differed in frequency structure. Also, evidence is provided that A. quecketti males call at high frequencies. The success of A. quecketti in urban environments as observed in Chapter 2 is described in terms of this species’ extensive repertoire and unusual frequency structure.
CHAPTER SIX provides insight into the effects of atmospheric conditions on the calling behaviour of Amietia quecketti, giving the proximate impact urbanisation has on weather conditions as well as the potential impact human activities can have on climate change on the long term. Calling activity was monitored over a nine-week period together with data from a mobile weather station which logged atmospheric variables every five minutes. Amietia quecketti was found to call most intensely between 00h00 and 03h00 in the morning and was most active in May, June and August. Humidity, temperature and wind velocity were found to have significant effects (P<0.05) on the calling activity of A. quecketti.
CHAPTER SEVEN is concerned with the attitudes of people towards frogs in South Africa. The first part of this study assessed the attitudes of people towards frogs in Potchefstroom. Surveys were distributed via the internet as well as manually to reach people with no internet access as well. Attitudes of people of Potchefstroom were mostly positive with more than half of the sampled population of 295 respondents indicating a strong liking in frogs. This study provides evidence that the presence of myths and knowledge can highly affects people’s attitudes towards frogs. The second part of this study focussed on the motivations of volunteers saving Western Leopard Toads from roadkill in Cape Town, South Africa. Volunteers were motivated by a strong value-driven approach to saving toads.
CHAPTER EIGHT provides a general discussion and outline on the contributions this study presented and also the new areas where more research is needed within the extent of the field of urban ecology from a South African perspective. / hD (Zoology), North-West University, Potchefstroom Campus, 2014
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Foraging and Roosting Behaviors of Rafinesque's Big-eared Bat (Corynorhinus rafinesquii) at the Northern Edge of the Species RangeJohnson, Joseph S 01 January 2012 (has links)
Bat populations in the eastern United States are currently declining at unprecedented rates as a result of habitat loss, commercial wind energy development, and white-nose syndrome. Effective conservation of these declining populations requires knowledge of several aspects of summer and winter ecology, including daytime habitat use (day-roost selection and social behaviors), nocturnal habitat use (foraging habitat selection, prey selection, and prey abundance), and winter hibernation (torpor) patterns. This dissertation addresses these questions for Rafinesque’s big-eared bat (Corynorhinus rafinesquii), a species of conservation concern in the southeastern United States. Kentucky represents the northern edge of the range of Rafinesque’s big-eared bat, and summer and winter behaviors in Kentucky are likely to differ from what has been observed in southern portion of the range, where available habitats and climate are different. My research occurred in two study areas in Kentucky, Mammoth Cave National Park in central Kentucky, and the Ballard Wildlife Management areas in western Kentucky. This dissertation includes all of the work done in western Kentucky, where I radio-tagged 48 adult big-eared bats and documented daytime and nighttime habitat use. Also included is a portion of the work done in central Kentucky, focusing on hibernation patterns of 14 adult big-eared bats radio-tagged during the winter at Mammoth Cave. Data disseminated in this dissertation provide insights into the summer and winter ecology of Rafinesque’s big-eared bat in Kentucky, and can be used to manage populations threatened by habitat loss and white-nose syndrome.
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Habitat Use By Early Successional Bird Species Along Powerline Rights Of Way: Making Connections Across Private LandsPeterson, Christine Rose 01 January 2015 (has links)
Wildlife species that rely on early successional habitat are showing long-term region-wide declines, including songbirds such as Eastern Towhee (Pipilo erythrophthalmus), Field Sparrow (Spizella pusilla), Blue-winged Warbler (Vermivora cyanoptera), Golden-winged Warbler (Vermivora chrysoptera), Prairie Warbler (Setophaga discolor), and Brown Thrasher (Toxostoma rufum). All six species are listed as Species of Greatest Conservation Need on a majority of the New England state's Wildlife Action Plans and in 2011, the Golden-winged Warbler was placed under review for federal listing. In areas where vegetation structure is actively maintained in early successional stages, such as powerline rights-of-way (ROWs), there is an opportunity to provide habitat over long time frames. This study focused on habitat use by six early successional bird species in the Champlain Valley in Vermont along powerline ROWs. Thirty sites that included potential habitat were established. During the breeding season, trained citizen scientist volunteers spot-mapped species distribution patterns along transects. Focal habitat use by individuals was mapped during timed field observations (n=83). Vegetation species composition and structure was evaluated within 1m2 vegetation plots across each site (n=965). Logistic regression models of study species' abundance patterns and focal habitat use were compared using Akaike's information criterion (AIC). Surrounding landscape composition, vegetation species composition and vegetation structure had the greatest influence on species abundance and focal habitat use based on best-fit models. All species occurrence, except Blue-winged Warbler and Brown Thrasher, decreased with greater development and fragmentation in the surrounding landscape. While the covariates that influenced habitat use patterns by the species were similar, the effect size and direction of influence varied. These results suggest that a universal management approach for shrubland songbird habitat would not support a broad range of species. The findings from this study determined species-specific habitat preferences that can improve management practices to benefit these declining species.
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