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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.
11

Mutualistic interactions between the nectar-feeding little red flying-fox Pteropus scapulatus (Chiroptera: Pteropodidae) and flowering eucalypts (Myrtaceae): habitat utilisation and pollination

Birt, P. K. Unknown Date (has links)
No description available.
12

Mutualistic interactions between the nectar-feeding little red flying-fox Pteropus scapulatus (Chiroptera: Pteropodidae) and flowering eucalypts (Myrtaceae): habitat utilisation and pollination

Birt, P. K. Unknown Date (has links)
No description available.
13

Mutualistic interactions between the nectar-feeding little red flying-fox Pteropus scapulatus (Chiroptera: Pteropodidae) and flowering eucalypts (Myrtaceae): habitat utilisation and pollination

Birt, P. K. Unknown Date (has links)
No description available.
14

Mutualistic interactions between the nectar-feeding little red flying-fox Pteropus scapulatus (Chiroptera: Pteropodidae) and flowering eucalypts (Myrtaceae): habitat utilisation and pollination

Birt, P. K. Unknown Date (has links)
No description available.
15

Demography and distribution of the North Island robin (Petroica longipes) in a fragmented agricultural landscape of New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctorate of Philosophy in Ecology at Massey University, Palmerston North, New Zealand

Richard, Yvan January 2007 (has links)
Habitat loss and fragmentation are recognised worldwide as contributing to declines and extinctions of species. However, the biological factors underlying the effects of fragmentation are still often poorly understood, possibly due to the diversity of scales and approaches taken by researchers. I propose in this thesis an integrative approach that can be applied to any taxa and landscape, using a metapopulation of North Island robins (Petroica longipes) inhabiting forest patches of a fragmented agricultural landscape of New Zealand. In particular, I attempt to integrate the effects of habitat fragmentation on both habitat quality and the dispersal-driven broad scale dynamics of populations. I first analysed the distribution of robins based on presence-absence data, relating presence-absence to local habitat factors as well as size and isolation of forest patches (Chapter 2). Their distribution was found to be primarily limited by the isolation of forest patches, but was also related to some habitat factors. However, habitat fragmentation was not found to affect habitat quality, as the factors found to affect survival and productivity were unrelated to size and isolation, independent from the size or isolation of forest patches (Chapter 3). Based on the radio-tracking of juvenile robins, I applied a choice analysis technique to show that robins need woody vegetation for their natal dispersal and that they are unlikely to cross stretches of pasture greater than 150 m (Chapter 4). Juveniles dispersed a median Euclidean distance of 1129 m with a maximum of 11 km, whereas I predicted from the data that they would have dispersed a median distance of 3 km in continuous forest with a maximum of 20 km (Chapter 5). The consequences of this dispersal limitation and of variations in habitat quality were assessed using a spatially-explicit individual-based metapopulation model that incorporated realistic gap-limited dispersal behaviour of juvenile robins (Chapter 6). Whereas the movement of individuals between patches is commonly assumed to improve the persistence of populations, I found that a weaker gap-crossing ability, and therefore reduced landscape connectivity, increased the metapopulation size at equilibrium. This study highlights the complex effects of habitat loss and fragmentation on the distribution of species, but also the limits of excessive model simplification.
16

Mutualistic interactions between the nectar-feeding little red flying-fox Pteropus scapulatus (Chiroptera: Pteropodidae) and flowering eucalypts (Myrtaceae): habitat utilisation and pollination

Birt, P. K. Unknown Date (has links)
No description available.
17

APPLICATION OF ADVANCED DIGITAL TECHNOLOGY FOR WILDLIFE HABITAT MODELING

Jessica Marie Elliott (12470109) 28 April 2022 (has links)
<p>  </p> <p>In recent decades, wildlife studies have begun to incorporate more structural characteristics into studies of habitat. However, most still collect habitat data primarily from field measurements, which are limited in spatial extent and force researchers to extrapolate from small-scale, ground-based measures. LiDAR offers the opportunity to objectively measure habitat features across landscape-level extents. I mapped and measured forest canopy structural diversity at 181 plots across Indiana at a series of three (25-m, 50-m, and 100-m) radii to quantify landscape heterogeneity across space, utilizing new 2016–2020 aerial LiDAR in tandem with high-resolution camera traps. I aimed to quantify the relationship between use of forest sites by seven wildlife species and habitat structural characteristics, specifically predicting species occupancy as a function of LiDAR-derived metrics. I predicted that habitat generalists like raccoons (<em>Procyon lotor</em>) and Virginia opossum (<em>Didelphis virginiana</em>) would be best predicted by the null hypothesis and that measures of gap fraction would best predict edge species such as coyote (<em>Canis latrans</em>), white-tailed deer (<em>Odocoileus virginianus</em>), and wild turkey (<em>Meleagris gallopavo</em>). Additionally, I predicted a positive relationship between vegetation area and both eastern cottontail rabbit (<em>Sylvilagus floridanus</em>) and tree squirrels (Sciuridae spp.). I expected that measures of habitat heterogeneity would be included in best models for tree squirrels and white-tailed deer, and that models for squirrels would have lower root mean square error (RMSE) values. Ultimately, structural metrics varied across radii, and best models depended on plot radius size. Measures of vertical heterogeneity were the best predictors for species like raccoon, wild turkey, and coyote, with a higher probability of occupancy for all three with increased heterogeneity. Additionally, models for eastern cottontail rabbit incorporating vegetation area indices, Gini diversity, and gap fraction demonstrated significance and low predictive error. Habitat generalists, such as white-tailed deer and Virginia opossum did not select for specific structural metrics and were best predicted by the null model. Ultimately, these results indicated that LiDAR is a promising potential tool for measuring ecologically meaningful variables at scales large enough to properly represent home range and resource use at the home-range level, filling an important gap in our understanding. </p>
18

PUBLIC PERCEPTIONS AND VALUATION OF WILDLIFE IN THE U.S.

Nicholas A Lancaster (7042940) 13 June 2023 (has links)
<p>Chapter 1: Currently there is no hunting or trapping season on bobcats in Indiana. While a season is being considered by wildlife administrators, there is no basis for establishing a price or understanding potential demand for this species. We use contingent valuation to estimate furbearer hunter and trapper willingness-to-pay (WTP) for a hypothetical bobcat harvest permit in Indiana, USA. Using a mail survey of 2000 randomly selected Indiana registered hunters and trappers, we presented respondents with a description of a hypothetical harvest season, including season dates, equipment restrictions, check-in procedures, counties open for the legal harvest, bag limit (the number of animals that can be legally harvested per individual), and statewide quota (the number of animals that can be legally harvested in aggregate). Following the description, respondents were asked a single-bounded dichotomous choice question about purchasing the proposed permit. By applying the Turnbull estimation method to our collected data, we estimate mean WTP of $21.73 for the proposed permit. Our estimates are sensitive to scope effects, which may be linked to perceived congestion: if hunters believe the bag limit may not be filled, WTP may actually decrease with the bag limit due to perceived congestion, necessitating the simultaneous examination of the bag limit and statewide quota.</p> <p><br></p> <p>Chapter 2: One Health initiatives employed by the Centers for Disease Control and Prevention place emphasis on the interconnectedness of animals, people, plants, and the environment. As new disease threats emerge, the interactions of humans and animals with their environments becomes increasingly important. Deer represent a large, prolific, and suitable host for several diseases that are potentially threatening in the One Health context. Previous works have studied deer-related diseases, such as Bovine tuberculosis and Lyme Disease, and examined risks of transmission in households of varying compositions, such as with and without pets or children. However, research quantifying public perceptions of deer and their role(s) in modern society is lacking. Our research applies social media listening to study perceptions of deer among the general U.S. population through volume (number of mentions) and assessment of tone, in terms of positivity versus negativity (analyzed as online media net sentiment). We study media about five prominent deer-related diseases from January 2018 through December 2021 and demonstrate that while aggregate mentions of the deer diseases we study compose a small proportion of total mentions for deer, net sentiment surrounding outbreaks reflects the seriousness of the health consequences these present. Additionally, we explain fluctuations in deer-disease mentions and net sentiment through real-world events, and demonstrate seasonality in mentions and net sentiment for some diseases of interest. Better understanding of public perceptions of the roles of wildlife, particularly deer who are generally perceived as non-threatening wildlife, is particularly important in today’s One Health context.</p> <p><br></p> <p>Chapter 3: The presence of deer in shared environments with humans may result in both positive and negative affinity towards deer. While literature shows deer-related damages to humans and their property, literature also suggests that deer are a way for humans to connect with nature. Managing deer populations is vital to balancing the positive and negative impacts of deer. Currently, hunting is the most cost-effective way to manage deer populations. We are interested in how hunting impacts the affinity for deer, in addition to how the COVID-19 pandemic plays a role in the perception of deer. Online media posts were analyzed using a social media listening platform, NetBase, for the time period of January 1, 2018 to December 31, 2021. Volume of mentions and affinity via net sentiment were collected at the state level on a weekly basis, and the national level on a daily basis. We utilize an OLS regression with dummies for deer hunting season and COVID at the state level to determine the impacts of hunting seasons and the pandemic on net sentiment. We find that deer hunting being open negatively impacts net sentiment of deer. We utilize Pearson correlations to study the impact of deer management via OTC deer hunting privilege issuance in relation to affinity for deer. We find that OTC privilege issuance is positively correlated with affinity for deer in some states, but the impact on affinity may diminish over time.</p>
19

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.
20

Effects of translocation on kokako (Callaeas cinerea wilsoni) song and its application to management : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand

Van Herpt, Sarah Michelle January 2009 (has links)
This thesis fills a research gap in our knowledge of kokako song by looking at how song evolves in multi-dialect areas. Kokako only exist in small remnant populations separated by large tracts of unsuitable land. Kokako are very poor flyers, only able to fly for approximately 100 metres at a time. In order to prevent inbreeding and a loss of genetic diversity in the remaining kokako populations, managers are carrying out translocations to establish new populations, maintain gene flow and prevent inbreeding. However, these translocations have the potential to be unsuccessful because kokako exhibit macrogeographic variation in their dialects, and tend not to breed with individuals who do not share the same dialect as them. If the purpose of the translocation is to enhance genetic diversity by having kokako from different areas breed then song is an important factor that must be dealt with. Song is extremely important to kokako for a number of reasons. Chiefly, it is hypothesised that song is their primary means of territory defence. A kokako gains all its resources from its territory, so it is imperative that they successfully defend it. Their duet song functions in territory defence, but also acts to form and maintain pair bonds. In order to try and address the problem that song causes in translocations I studied if and how song evolves in a multiple dialect area. I conducted research at Pukaha Mount Bruce, where there is a population of kokako originating from two different source populations, and thus two different dialects, Northern Mapara and Mangatutu. I looked at the Northern Mapara dialect, and recorded kokako belonging to three groups; kokako currently living in the source population, kokako that were translocated to Pukaha and kokako that were born at Pukaha. In order to determine how the song may be changing I looked at element repertoires, the levels of sharing between groups, the number of unique elements in repertoires and the syntactical and temporal characteristics of phrases. This study shows that translocation into multiple dialect areas can affect kokako song. Translocation did not affect the size of the kokako repertoire, but it seemed to affect the amount of sharing within and between different groups of kokako. Currently the level of sharing within the groups at Pukaha is lower than the level of sharing within the source Mapara population, indicating that the song may be diverging. There also seem to be more unique elements found at Pukaha, which in part explains the lack of sharing. There appears to be microgeographic variation at Pukaha, with birds clustered around the second (Mangatutu) dialect sharing less with the source population than do those kokako whose territories are lower down in the reserve. The phrases which are used are also evolving, with only one phrase truly shared among all groups. There are other phrases which show additions or deletions of elements, and so are evolving. The main change found in the phrases is the timing between elements, with six out of seven phrases examined showing changes. These results have repercussions for future kokako translocations, and the future of the Pukaha kokako. A low amount of phrase and element type sharing combined with changes of intra-phrase timing could lead to the Pukaha kokako’s inability to successfully defend their territories. This research shows how kokako song can give conservation managers information on the status of their populations in regards to interbreeding and raises questions which can be answered by further research, both at Pukaha and in other mixeddialect kokako populations.

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