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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.
1

DNA fingerprinting analysis of captive Asian elephants, Elephas maximas

Bischof, Laura Louise 01 January 1990 (has links)
This thesis examined the effectiveness of DNA fingerprinting analysis for paternity ascertainment and the establishment of relatedness of captive Asian elephants (Elephas maximas). Eighteen Asian elephants from three North .American zoos were examined. Thirteen of these elephants were wild caught. Relationships between these elephants and the remaining elephants born in captivity were known.
2

A study on elephant and human interactions in Kodagu, South India

Narayana, Malavika Hosahally January 2014 (has links)
Increasing human populations have resulted in the extensive conversion of natural forests and range lands into agricultural lands, resulting in an expansion of the interface between people and elephants across the elephant range countries of Asia and Africa. This interface describes the nature of two-way interactions between people and elephants, which can be positive and reverential or hostile and negative. Elephant crop-raiding, one of the most negative interactions for people at the interface, is not only the result of decreased food resources and space, but has also been attributed to a preference for cultivated crops and to damage caused during elephant movements between habitats. The aim of this thesis was an attempt to understand the use of coffee agroforestry areas by elephant populations in a South Indian district, Kodagu, and to assess the risks to elephants and people of coffee plantations. Geographically, located at a significant position in the Western Ghats, Kodagu district is a part of one of the largest wild Asian elephant ranges harbouring India’s largest elephant population. Kodagu has a unique topography and coffee agroforestry system in considered as the boon for conservation. This thesis is the first long term (one year) study on the elephant populations using coffee estates in Kodagu. Crop-raiding events across Kodagu and their intensity of occurrence were determined from the Forest Department compensation records. Virjapet taluk was one of the three administrative units of Kodagu with frequent incidences of crop-raiding, including elephant mortality and human deaths. High rates of crop-damage in Virajpet included both coffee and paddy rice produce as the land is conducive for the cultivation of both. To understand the use of coffee estates by elephants, coffee estates in Virjapet were directly and indirectly monitored for the presence of elephants using dung sampling (N=202), camera trapping, video and photo documentation, as well as sightings (N=408) and reports by local workers, in order to identify the individuals or groups of elephants frequenting these coffee estates. Lone male and all male groups used coffee estates most frequently and family herds ranging in group size from 2 to 10 were present mainly during the peak season of coffee ripening (post monsoon). Presence of large numbers of elephants, especially with large female groups, was associated with crop-damage during the months of December-January. As seasonal movements of elephants in Kodagu districts are still not known, it is unclear why the number of elephants in coffee estates post-monsoon increases when food availability should also be higher in forests. These large coffee estates were used as refuge areas by elephants during the day by all individuals and groups, and feeding on estates occurred during the night to early morning hours. Dung analysis and observations suggested that coffee estates were attractive for elephants due to the constant availability of water (for irrigation), green fodder, and cultivated fruit trees, especially jackfruit. Coffee plants were damaged both due to consumption (47% of dung samples in this study) and accidental damage during elephant movements within the estates. Although the dung sampling could not confirm whether coffee had become a novel food resource, the presence of large number of elephants during the coffee ripening season suggested that the potential for coffee berries to be added regularly to the diet in the future, with potential consequences for coffee invasion of native forests through dung seed dispersal. People working on large coffee estates were accustomed to the presence of elephants and were generally knowledgeable of the areas that elephants frequented, thus avoiding fatal encounters. However, safety of farmers and other people working on the estates remains a major concern, especially for large coffee estates owners. The constant interaction between elephants and people also led to more negative perceptions of elephants, and reduced the tolerance of elephants in the area. The unique topography of Kodagu as a mosaic of forests and farms challenges the number of possible mitigation methods to prevent negative encounters between people and elephant. The elephants of Kodagu may have adapted behaviourally to the presence of people, but long-term monitoring of the elephant population is important to understand their ecological and social adaptations to the various costs and benefits of using this agroforestry landscape. Suggestions for management of the elephant-human interface and mitigation of negative attitudes and actions were made, through a model that incorporates a multiple stakeholder (including elephants) action plan.
3

Analysis and Classification of Sounds Produced by Asian Elephants (Elephas Maximus)

Glaeser, Sharon Stuart 01 January 2009 (has links)
Relatively little is known about the vocal repertoire of Asian elephants (Elephas maximus), and a categorization of basic call types and modifications of these call types by quantitative acoustic parameters is needed to examine acoustic variability within and among call types, to examine individuality, to determine communicative function of calls via playback, to compare species and populations, and to develop rigorous call recognition algorithms for monitoring populations. This study defines an acoustic repertoire of Asian elephants based on acoustic parameters, compares repertoire usage among groups and individuals, and validates structural distinction among call types through comparison of manual and automated classification methods. Recordings were made of captive elephants at the Oregon Zoo in Portland, OR, USA, and of domesticated elephants in Thailand. Acoustic and behavioral data were collected in a variety of social contexts and environmental noise conditions. Calls were classified using perceptual aural cues plus visual inspection of spectrograms, then acoustic features were measured, then automated classification was run. The final repertoire was defined by six basic call types (Bark, Roar, Rumble, Bark, Squeal, Squeal, and Trumpet), five call combinations and modifications with these basic calls forming their constituent parts (Roar-Rumble, Squeal-Squeak, Squeak train, Squeak-Bark, and Trumpet-Roar), and the Blow. Given the consistency of classifications results for calls from geographically and socially disparate subject groups, it seems possible that automated call detection algorithms could be developed for acoustic monitoring of Asian elephants.
4

Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus)

Velonis, Heather Kelly 08 June 2017 (has links)
Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately predict parturition can have a direct impact on elephant welfare. Elephants in captivity often require significant preparation and management throughout the birthing process, and complications during labor and delivery can necessitate immediate intervention, including stillbirth, protracted labor, maternal aggression towards a newborn calf, and dystocia. Being able to predict when parturition will commence can ensure appropriate staff is available and adequate monitoring is performed. Routine endocrine sampling can be used to predict parturition in Asian elephants, with a drop in progesterone (P4) to baseline levels signaling parturition in 2-5 days. However, we determined this method is not without limitations, and it is not used in all institutions that house elephants. As changes in hormones regulate and alter behaviors, we investigated behavioral indicators as an additional management tool for predicting parturition, a time of drastic hormone changes. We conducted a study of five pregnancies in Asian elephants at the Oregon Zoo, U.S.A, and Taronga Zoo, Australia, between 2008 and 2012. In Chapter 2, I evaluated progesterone (P4) and cortisol levels across three time periods: Baseline; Pre, (the week preceding the drop in P4); and Post, (the period after the P4 drop). Levels of P4 were significantly lower, and levels of cortisol were significantly higher in the days just prior to parturition. I found considerable intra- and inter-individual variation in both endocrine profiles, which can make endocrine assessments difficult to interpret in real time. In Chapter 3, I investigated whether behaviors in the preparturition period could be predictive of impending parturition in the Asian elephant. ANOVA results indicated a significant difference in the amount of time that elephants spent walking backwards across three time periods (F(2) = 3.723, p = 0.033), with the behavior increasing as parturition approached. These results were supported by a non-parametric Kruskal- Wallis. Using a generalized linear mixed model (GLMM), I found that as P4 levels decrease, walking backwards behavior significantly increases. In Chapter 4, I evaluated investigative trunk behaviors, or "trunk checks", directed towards the temporal gland near the ear, mammary glands, vulva and anus of the pregnant dam. Investigative behaviors included both self-directed behaviors and those sent from herd mates towards the pregnant dam. Self-directed behaviors are most likely associated with physical changes in the pregnant dam, such as using the trunk to pull on swollen teats. Other-directed behaviors may stem from chemo-sensory signaling or other types of communication between herd mates, such as detecting changes in progesterone or cortisol. I ran GLMM and found that four trunk-check behaviors varied significantly with P4 and/or cortisol profiles. These were: self-checks of mammary glands increased with decreasing P4 levels; herd-mate-checks of mammary glands increased with decreasing P4 levels; self-checks of vulva increased with decreasing P4 levels and increasing cortisol levels; herd-mate-checks of anus increased with increasing cortisol levels. In Chapter 5, I evaluated activity budget behaviors in the pregnant elephants. Generalized comparisons were made to published activity budgets of typical captive Asian elephants. I report that activity budgets are within the range of normal activity, though I note a high level of inter-individual variation. In addition, I compared two sampling techniques, including one-zero and instantaneous sampling, that were used for activity budget data collection. I discuss the different results obtained by each sampling technique. These results are a very promising indication that behaviors, including walking backwards and multiple trunk-check behaviors, are changing over time or with parturition-related hormone profiles. We recommend that keepers, veterinary staff, and other observers that are familiar with the regular behavioral repertoire of a pregnant female should pay close attention to these highlighted behaviors. Keeping track of these behaviors, especially in conjunction with P4 and cortisol tracking, can help staff refine existing windows of expected parturition.
5

Applying GPS and Accelerometers to the Study of African Savanna (Loxodonta africana) and Asian Elephant (Elephas maximus) Welfare in Zoos

Holdgate, Matthew Robert 16 March 2015 (has links)
African savanna elephants (Loxodonta africana) and Asian elephants (Elephas maximus) are a focus of welfare research in zoos due to their high intelligence, complex social structure, and sheer size. Due to these challenges, some argue that zoos are inherently incapable of providing appropriate care for elephants, while others believe that zoos can fulfill the needs of these species with improved husbandry. There is a general consensus from both within and outside of zoos, however, that zoos must improve their elephant programs or cease exhibiting these animals altogether. Now more than ever, applied research on zoo elephant welfare is needed to provide context for this debate. Researchers are interested in how far zoo elephants walk due to the potential health and welfare benefits of walking in these highly mobile species. Zoo researchers recently adopted GPS technology to study elephant walking, and preliminary evidence suggests that African elephants in large zoo exhibits walk distances that correspond with wild elephants under non-extreme conditions. However, data are limited from Asian elephants and from elephants in more typically-sized exhibits. In Chapter Two, I discuss important methodological considerations of utilizing GPS in a zoo environment, including an introduction to the technology, sources of error and mitigation, methods to improve GPS performance, and possible effects of GPS device attachment on animal behavior. This review shows GPS performance is adequate for tracking zoo elephant walking when proper methodological techniques are applied, and should serve as a useful reference for zoo researchers considering using GPS. In Chapter Three, I used GPS anklets to measure outdoor daily walking distance in 56 adult female African (n = 33) and Asian (n = 23) elephants housed in 30 zoos. I collected 259 days of data and found that elephants walked an average of 5.34 km/day with no significant difference between species. Multivariate regression models predicted that elephants with more dynamic feeding regimens (more diverse feeding types and frequencies; unscheduled feeding times) will walk more. Distance walked was also predicted to be higher in elephants that spend time in a greater number of different social groups. Distance walked was predicted to decline with age. Finally, I found a significant negative correlation between distance walked and nighttime space experience. The results of the analysis suggest that zoos that want to increase walking in their elephants need not rely solely on larger exhibits, but can increase walking by adding quality and complexity to exhibits. However, my results failed to establish a definitive link between walking distance and other validated measures of elephant welfare. Thus, the direct health and welfare benefits of walking in zoo elephants remain unresolved. Resting behaviors are an essential component of animal welfare, but have received little attention in zoological research. In Chapter Four, I used accelerometers in anklets to complete the first large-scale multi-species investigation of zoo elephant recumbence. I collected 344 days of data from 72 adult female African (n = 44) and Asian (n = 28) elephants at 40 zoos. I found that African elephants are recumbent an average of 2.14 hours/day, which is significantly less than Asian elephants at 3.22 hours/day. Multivariate regression models predicted that African elephant recumbence increases when they experience more space at night, and Asian elephant recumbence increases when they spend time housed alone. Both species showed a similar response to substrate, such that African elephants spending time on all-hard substrates are predicted to be recumbent less, while Asian elephants spending time on all-soft substrates are predicted to be recumbent more. The discovery that occasional non-recumbence is a common behavior in zoo elephants also introduces a new area of research that may have important animal welfare consequences. Finally, this study established that zoos should continue their efforts to replace hard substrate with soft substrate in order to provide zoo elephants with environments that facilitate recumbence. Overall, this work assessed walking and recumbence in zoo elephants, which will allow zoos to gauge the prevalence of these behaviors in their elephants as compared to the sub-population studied here. A variety of factors that are associated with these behaviors were also identified. With this information, zoos can prioritize modifications to their facilities and animal management programs to create an environment that encourages zoo elephants to express walking and recumbence behavior, should they choose to do so. This work is one component of the Elephant Welfare Project, the largest zoo animal welfare project ever undertaken, and is unprecedented in both scope and scale. The project was funded by the Institute of Museum and Library Services (IMLS), an independent, U.S., federal, grant-making agency that supports libraries, museums, and zoos. At the time of this writing, the first manuscripts from this project are being submitted to academic journals. These papers will describe the prevalence and distribution of a variety of elephant behaviors and welfare indicators, serve as a benchmark for future elephant welfare studies, and aid in decision making with regard to best practices in elephant management.

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