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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

Survival rate estimates of Florida manatees (Trichechus manatus latirostris) using carcass recovery data

Schwarz, Lisa Kimberley. January 2007 (has links) (PDF)
Thesis (Ph. D.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Daniel Goodman. Includes bibliographical references (leaves 124-144).
2

Quantitative evaluation of a boater education program for manatee protection

Morris, Julie. January 2004 (has links) (PDF)
Thesis (M.S.)--University of Florida, 2004. / Title from PDF title page (viewed on July 7, 2005). Includes vita. Includes bibliographical references (p. 83-85).
3

Seasonal habitat use of the Florida manatee (Trichecus manatus latirostris) in the Crystal River National Wild[l]ife Refuge with regards to natural and anthropogenic factors

Berger, Ryan W. January 2007 (has links) (PDF)
Thesis (M.S.)--Georgia Southern University, 2007. / Title from PDF title page (viewed on Feb. 19, 2008). Electronic version approved: May 2007. Vita. Includes bibliographical references.
4

The role of science in the creation of endangered species law and policy the case of the West Indian manatee /

Goedeke, Theresa L. January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 520-556). Also available on the Internet.
5

The role of science in the creation of endangered species law and policy : the case of the West Indian manatee /

Goedeke, Theresa L. January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 520-556). Also available on the Internet.
6

Regionalization of Scar Patterns on the Florida Manatee (Trichechus manatus latirostris) Observed at Harbor Branch Oceanographic Institute, Florida.

Unknown Date (has links)
The Florida manatee (Trichechus manatus latirostris) is native to Florida and the Indian River Lagoon. Harbor Branch Oceanographic Institute (HBOI) is located in Indian River Lagoon and is frequently visited by manatees. The Manatee Project was created in 2009 to document and photograph the manatees visiting HBOI. Analyzing photographs of 146 manatee that visited HBOI showed that a majority of the injuries sustained were caused by boats. 97% of the manatee had at least one propeller injury and 31% of the manatee had at least one skeg injury. Other non-boat related injuries seen in the images included cold stress and entanglement injuries. This study looked at the prevalence of scar by anatomical region, the cause of injury, and compared injury locations between male and female manatees. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
7

Sound localization abilities of two Florida manatees, trichechus manatus latirostris

Colbert, Debborah E 01 June 2005 (has links)
Florida manatees (Trichechus manatus latirostris) live in the shallow, often turbid inland and coastal waters of the southeastern United States. Since their vision is poor (Bauer et al., 2003), other senses probably guide orientation. Previous studies have found that manatees can hear over 40 kHz (Gerstein et al., 1999) and have the capacity for rapid auditory temporal processing (Mann et al., 2005). However, it is not known if manatees have the ability to localize underwater sounds. Two Florida manatees were trained to identify underwater sound source locations using a four-choice discrimination paradigm. Three broad-band signals ( 0.2 - 20, 6 - 20, and 0.2 2kHz) were tested at four durations (3,000, 1,000, 500, and 200ms) and two tonal signals (4 and 16kHz) were tested with a 3,000ms duration. A total of 1,008 test trials were analyzed per subject. Both manatees learned the task easily, and could localize all of the test signals at a performance rate well above the 25% chance level. Within all of the broad-band conditions, performance accuracy ranged from 93% - 79% for Buffett, and 93% - 51% for Hugh. Broad-band signal duration did not have an effect on performance accuracy with Buffett who ranged from 89% to 87%, but did with Hugh who ranged from 87% - 58%. Broad-band frequency type did not have an effect on performance accuracy with Buffett who averaged 90%, 86%, and 89%, but may have with Hugh who averaged from 76%, 68%, and 65% at the 0.2 20, 6 20, and 0.2 2 kHz conditions. Both animals performed above chance levels with the pure tone signals, but at a much lower accuracy rate with Hugh at 49% and 32% and Buffett at 44% and 33% with the 4 kHz and 16 kHz conditions. Results from this experiment provide information about the manatees ability to localize different types of sounds in a controlled environment. This knowledge is important for understanding how manatees detect and localize noise generated from conspecifics and boat engines and contributes to making competent conservation management decisions about these endangered marine mammals.
8

Call Categorization and Vocal Behavior of the Florida Manatee (Trichechus manatus latirostris)

Unknown Date (has links)
Florida manatees are semisocial marine mammals that vocalize when interacting with conspecifics and to maintain contact with offspring. While many aspects of their biology have been studied, there is a dearth of information on the diversity and complexity of vocal behavior during social, nonsocial, and stressful situations. Investigations of vocal communication repertoires which define, categorize, and correlate varied call types with behavior are needed in order to understand the behavioral and social function of associated calls. Arguably the most important social bond in manatees is the period of cow/calf dependency and empirical evidence indicates cows recognize the vocalizations of offspring. Exploration of individually distinctive vocal features can provide insight on which parameters might be salient to facilitate recognition between cows/calves. This study is focused on vocal communication in Florida manatees, how calls are structured, utilized and function while animals are distressed and during social interactions in their shallow water habitats. Hydrophones recorded vocalizations from individual calves and manatees in different behavioral contexts and varying size aggregations. Analysis of the vocal repertoire indicated manatee vocalizations can be parsed into five broadly defined call types which include the hill-shaped high squeak, tonal squeak, noisy squeal, two toned chirp, and the combinatorial squeak-squeal. Furthermore, the high squeak is likely a discrete call whereas the others are graded and do not have strict boundaries between call types (Chapter 2). Broadly defined call types were used to explore call usage with variations in behavior, group size, and group composition (Chapter 3). Manatees vocalized using few call types and altered structural parameters depending on behavioral state. Calls were longer and more frequency modulated when stressed. Vocalizations produced while cavorting were higher in entropy and more frequency modulated than when manatees were resting or feeding. Vocalizations obtained from individual calves suggest that the high squeak is a stereotypical call that is produced by smaller calves. All calves had individually distinctive acoustic features that could potentially be used in recognition (Chapter 4). Lower fundamental frequencies and higher emphasized frequencies from smaller calves suggest that the fundamental frequency may not be a reliable indicator of body size in calves. This research increases our knowledge of the vocal behavior and call characteristics of the Florida manatee. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
9

Multi-Scale Habitat Selection of Antillean Manatees (Trichechus manatus manatus) in Sian Ka'an Biosphere Reserve, Southeastern Mexico

Gagnon, Émilie 06 September 2023 (has links)
The distribution of organisms across the globe forms non-random patterns that are based on their selection for certain environmental features. Habitat selection is the study of how organisms choose where they live. It is a fundamental behavior shaping several ecological and evolutionary processes. The hierarchical nature of the environment makes it imperative to consider multiple scales in habitat selection studies. Even though there is extensive coverage of scaling in habitat selection literature, most published papers only consider one scale. To our knowledge, habitat selection studies of the Antillean manatee (Trichechus manatus manatus) have never included more than one spatial scale. Hence, we modeled Antillean manatee habitat selection in the Sian Ka'an Biosphere Reserve, in Mexico, at two spatial scales: study area and 1 km buffer. We used GPS coordinates of opportunistic encounters (n = 102) recorded since 2009. We randomly generated 500 pseudo-absences per presence point for both scales, and extracted the environmental conditions from each point: seagrass abundance (leaf area index or LAI), water depth, and shortest distance to land, closest river and closest resting hole. We fitted a binomial regression of the probability of presence as a function of the environmental parameters using a Bayesian approach. Our results show that the probability of manatee presence increases in proximity to resting holes for both scales and increases with land proximity at the large-scale. Overall, we showed that proximity to resting holes is the most important feature of habitat selection for Antillean manatees in Sian Ka'an, followed by proximity to land. This study demonstrates the importance of multi-scale designs in habitat selection and highlights the need for more studies looking at the use and ecological implications of manatee resting holes.

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