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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

An analysis of hunter kill data

Tait, David E. N. January 1983 (has links)
A stochastic model is developed that can be used to compute the likelihood of observing a specific time stream of harvests of a wildlife population. The harvest is assumed to be a count of the total number of animals in each age in each sex in each year removed from the population for a sequence of consecutive years. In the stochastic model it is assumed that the harvest process and the natural survivorship process can both be treated as binomial processes. The recruitment process is approximated as a product of normal processes. This formulation allows for the development of an iterative numerical scheme that will reconstruct the most probable underlying unknown population given a set of harvest data and a set of life history parameters. A heuristic procedure that checks for internal consistency between the reconstructed population, the set of harvest data, and the life history parameters may be used to estimate a number of unknown population parameters together with the unknown population. The scheme has been tested with Monte Carlo simulations and, using only harvest data, has simultaneously estimated the survivorship rate, the recruitment rate, the male harvest rate, the female harvest rate and the yearly harvest effort together with the unknown population. The scheme has been applied to Alaskan brown bear harvest data demonstrating its potential value as a management tool. / Forestry, Faculty of / Graduate
42

An integrated data system for wildlife management

Kale, Lorne Wayne January 1979 (has links)
ID 1975 the British Columbia Fish and Wildlife Branch implemented the Management Unit system for controlling and monitoring wildlife harvests in the province. This change in management boundaries should have been accompanied by an intensified data handling system, so that accurate and reliable management indices could be produced for each M.U. This thesis describes a data system that was developed in response to Region 1 blacktailed deer management needs and offers a new approach to wildlife data system management. The proposed system integrates field contact and hunter questionnaire data, and allows managers to monitor the effects of their policy decisions. Management strategies can be tested by manipulating exploitation parameters, such as bag limits and season lengths, to determine their effect on specific wildlife populations. In addition, the system restores and upgrades obsolete data files, thus allowing past harvest trends to be applied to new management zones. Flexibility, for both anticipated changes in resource stratification and unanticipated data needs, is also preserved. Biologists require management estimates for specific areas within M.U.s to manage wildlife effectively at the M.U. level. Each of the 15 M.U.s in Region 1 have been subdivided into between 5 and 32 subunits, depending on area and geography. The total 246 subunits attempt to partition large unmanageable wildlife resources into separate populations of manageable size. A location list or computerized gazetteer was used to automatically assign hunt location descriptions to appropriate M.U.s and subunits. Hew techniques for hunter sample estimates are proposed in this thesis. Mark-recapture methods for determining sampling intensities and the partitioning of large resident areas into resident M.U.s can improve estimates. Different methods for treating multiple mailing stage data are also presented. The data system described in this thesis consists of two parts; 1) the establishment of master data files and 2) the retrieval of data from those files. Five subsystems of PORTBAN computer programs control the input of Fish and Wildlife harvest data and manipulate them into master data files. The information retrieval is accomplished by standard statistical packages, such as SPSS. A hierarchial file structure is used to store the harvest data, thus most wildlife management data requests can be answered directly. The 1975 Region 1 blacktailed deer harvest data were used to test the sampling assumptions in both the hunter sample and field contact programs. Significant differences between resident M.U.s were found for hunter sample sampling intensity, percentage response, percentage sampled, and percentage of hunters among respondents. Significant differences were established in the percentage hunter success in different resident M.U.s and for different mailing phases. The 1975 field contact program produced a non-uniform distribution of contacts with respect to M.U.s. Highly significant differences between the percentage of licence holders checked from different resident M.U.s were also found. Kills for field checked hunters who also responded to the hunter sample questionnaire were compared to kills reported on the questionnaire. Numerous irregularities, including unreported kills, misreported kills, and totals exceeding bag limits, were found and a minimum error rate of about 20% was calculated. Known buck kills were generally (87.9%) reported as bucks, while does were only reported correctly 74.% of the time, and fawns only 48.0%. The format of the 1975 deer hunter questionnaire is suspected to have influenced those error rates. Successful and unsuccessful hunters had different probabilities of responding to the hunter questionnaire. Only 48.0% of unsuccessful hunters responded, while 59.6% of successful hunters reported. Hunter sample harvest estimates using different estimation methods were compared to known kills in two Vancouver Island subunits. During the 1975 season, 88 deer were shot in subunit 1-5-3 Nanaimo River), while 140 were estimated to have been shot in subunit 1-5-7 (Northwest Bay), all estimated kills were considerable higher than the known harvest, with the marked success-phase mailing estimation method producing the lowest estimates — 170 deer (193%) for subunit 15-3 and 179 deer (127%) for subunit 1-5-7. Although the total estimated deer kill for Vancouver Island remained relatively constant from 1964 to 1974, the same data when analysed by M.U. and subunit showed decreasing harvests in some M.U.s and subunits which were balanced by increasing kills in others., The data system proposed in this thesis provides an opportunity for B.C. wildlife management to develop an effective management framework for B.C.'s valuable wildlife resources. However, to do so the proposed system or one with similar capabilities must be implemented and supported by the B. C. Fish and Wildlife Branch. / Land and Food Systems, Faculty of / Graduate
43

Roosting, site fidelity, and food sources of urban gulls in massachusetts: Implications for protecting public water supplies

Clark, 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.
44

Using activity budgets and space use preferences to define enclosure appropriateness for African painted dogs, Lycaon pictus (Temminck 1820)

Hunter Burnam, Sally C. January 2020 (has links)
As natural habitat is lost, the need for keeping and breeding animals in zoological gardens is increasing. For animal welfare reasons and to promote health and effective breeding having as close to natural enclosures has become essential on zoological gardens. A clear understanding of how an animal uses its space and activity budgets may be required to understand their biological requirements more fully in zoological environments. The findings in these behaviour observations will aid the design of exhibits and, in turn, potentially maximize the animals’ welfare. The welfare of animals in human care often has been examined in relation to the amount of space provided. However, more recently, welfare has been assessed by the quantity and the quality of the space being given. In this study, I examined two different packs of African painted dogs (Lycaon pictus) in two separate outside, naturalistic enclosures at the San Diego Zoo (SDZ) and Bronx Zoo (BZ). I use electivity indices as a tool to determine under and over-utilized exhibit areas. This type of index provides a novel way of measuring spatial preferences. Areas that are used in greater proportion than their availability in the environment are considered over-utilized. Conversely, areas that are proportionately under-utilized are avoided. In this study, I also looked at “rest” and “locomotion” behaviours to determine if the African painted dogs in these zoos show the crepuscular activity of their wild counterparts. I also looked at “stereotypic” behaviours and whether they were more significant at specific times of day. Because of the crepuscular activity, complex social structure, and nomadic nature of painted dogs; managers of zoological facilities have a challenge ensuring a suitable exhibit for these animals. An activity budget formula was used for observations during each designated time frame (morning, noon, evening, and dusk) and the average behaviour during the entire day. This was found also to be highly influenced by the presence of humans. In this instance, the SDZ dogs preferred the area near the keeper area. The times that they were more active in the area, keepers were present, and therefore some of the dog’s behaviour could be attributed to the anticipation of movement or food. The lack of stereotypic behaviour in the BZ dogs was not expected, while the SDZ dogs may have only had higher instances of stereotypies because of the trauma within the pack. There is a risk of negatively influencing ‘natural’ behaviours of African painted dogs in zoological facilities. This study was completed to influence how zoological managers create ‘naturalistic’ exhibits for several different wide-ranging, nomadic, and charismatic species of carnivores. This research has influenced how I currently care for the Chinese dholes (Cuon alpinus) at the San Diego Zoo Safari Park. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2020. / Zoology and Entomology / MSc (Wildlife Management) / Restricted
45

Variation in abundance and body condition of the Meletse bat assemblage, Limpopo Province, South Africa

Shanahan, Monique January 2020 (has links)
More studies are needed to understand how bat assemblages vary temporally in conjunction with environmental factors. This study investigated the temporal variations in relative abundance and body condition of a bat species assemblage in relation to with temperature and rainfall variations. Bats were captured and recorded using passive (echolocation recordings) and active monitoring (mist net and harp trap captures). The temporal variation in relative abundance, activity and body condition as temperatures and rainfall changed. Temperature was the main factor that correlated with variations in relative abundance and activity for Rhinolophus blasii, Miniopterus natalensis, Scotophilus dinganii and Neoromicia zuluensis. Relative activity peaked from spring to summer and reduced from autumn to winter. Body condition was positively correlated with both temperature and rainfall for Hipposideros caffer, R. simulator, R. smithersi, Nycteris thebaica, Min. natalensis and S. dinganii. These results indicate that Forearm Mass Index (FMI) changes in autumn to winter for H. caffer, Min. natalensis and N. capensis, and in spring to summer for R. blasii, Ny. thebaica, Min natalensis, Myotis tricolor, S. dinganii, N. capensis, N. zuluensis and Pipistrellus rusticus. These variations are important when developing management systems in the Meletse mountains to monitor important seasonal changes. Monitoring should consider breeding seasons and key species such as Min. natalensis, R. blasii and R. simulator which were strongly correlated with temperature and rainfall variations. This study can serve as a baseline for long-term monitoring programmes to assess high-risk species and develop early warning systems for conservation. This information is also critical for national and international reporting programmes and illustrates the importance of incorporating multiple monitoring techniques in developing temporal monitoring programmes to accurately assess bat assemblages. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2020. / National Research Foundation (NRF) Ref: SFH160720180270 / The Rufford Foundation Ref: 23603-1 / Zoology and Entomology / MSc (Wildlife Management) / Unrestricted
46

Impacts of Amur Honeysuckle (<i>Lonicera maackii</i>) Removal on the Composition ofAvian Assemblages in Rural Riparian Forests

DeJong, Leanna January 2020 (has links)
No description available.
47

Proximate factors of migration in Miniopterus natalensis (A. Smith 1833) in north-eastern South Africa

Pretorius, Mariëtte Estelle January 2020 (has links)
Migration is one of the key evolutionary adaptations allowing animals to survive in a landscape with seasonally changing and geographically separated resources. Understanding the various underlying processes governing migration in species is crucial to the conservation of many migratory species. This is especially true for migratory bat species in South Africa, for which limited information is available and no conservation action plans are in place. In this thesis, I focus on investigating the different factors affecting migration in the cave-dwelling, insectivorous Natal long-fingered bat Miniopterus to ultimately better understand the process of migration, including the internal motivation to move, the physical ability to move, the timing of the movement and the external factors affecting movement. The populations of bats used for this study were located in a maternity cave in Thabazimbi, in Limpopo Province and an unconfirmed stopover cave in the Hennops River Valley, Gauteng Province, South Africa. Using long-term, historically collected data as well as data collected during this study, I investigated which climatic factors likely initiated migration, arrival and departure times at the maternity site and factors affecting nightly activity patterns (Chapters 2 and 3), the physiological needs of females during the maternity period and whether this species prepares for migration away from the site through fattening (Chapters 4 and 5), whether the sexes exhibit morphological differences in their ability to move (Chapter 6) and whether differential movement is detectable between the sexes using isotopic signatures (Chapter 7). Lastly, I summarised current known important roost localities for M. natalensis, assessed their current protection status and modelled likely migration paths between ecologically important roost sites (Chapter 8). My research provided novel information on the migratory processes of M. natalensis and will be useful for informing future conservation action plans for this and other cave dwelling bat species in South Africa. / Thesis (PhD (Wildlife Management))--University of Pretoria, 2020. / National Research Foundation / University of Pretoria / Rufford Foundation / Zoology and Entomology / PhD (Wildlife Management) / Unrestricted
48

Movements and Habitat Relationships of Virginia Rails and Soras within Impounded Coastal Wetlands of Northwest Ohio

Hengst, Nicole M. January 2021 (has links)
No description available.
49

Impacts of Coyotes (Canis latrans) on White-tailed Deer (Odocoileus virginianus) Behavior and Mortality in the Chicago Region

Anchor, Gretchen 08 July 2019 (has links)
No description available.
50

Population Demographics and Diet Variation of the North American River Otter (Lontracanadensis) in Ohio, USA

Adamczak, Sara January 2019 (has links)
No description available.

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