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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.
21

Haul out patterns and diet of harbor seals, Phoca vitulina, in Coos County, Oregon

Graybill, Michael Ray, 1954- 06 1900 (has links)
vii, 55 leaves : ill. ; 28 cm Typescript. (Another copy on microfilm is located in Archives) Thesis (M.S.)--University of Oregon Includes vita and abstract Bibliography: leaves 52-56 University of Oregon theses, Dept. of Biology, M.S., 1981
22

The seasonal movements and abundance dynamics of the Pacific harbor seal (Phoca vitulina richardsi) along the southern Oregon coast

Wilson, Michael Turner January 1993 (has links)
Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 84-90). Description: xiv, 90 leaves : ill. ; 29 cm.
23

Pearl Harbor a case study in administration /

Habbe, Donald Edwin, January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 255-260).
24

Revised map of California butt-in-bay magnified 1000 times /

January 1900 (has links)
Humorous map of California with faces and heads drawn around the bays of San Francisco and San Diego, holding a conversation about the "Los Angeles 'Navel' Station".
25

Hauling out behaviour of harbour seals : (Phoca vitulina richardsi), with particular attention to thermal constraints

Watts, Peter January 1991 (has links)
Harbour seals throughout their range are known to "haul out" onto land according to a daily cycle, which has never been fully investigated. This cycle may represent a tradeoff between the need to forage and the need to avoid aquatic predators; if so, seals should forage when prey availability is greatest and remain hauled at other times. A model based upon these premises accounted for approximately two thirds of the variation in observed hauling behaviour at a harbour seal colony in the Strait of Georgia, once other environmental effects had been filtered from the data. Some such effects could not be corrected for; since air temperature and solar radiation follow the same general pattern as that predicted by the hauling model, the possibility that hauling occurs in response to thermal conditions could not be excluded. This issue was addressed by correlating hauling activity at three seal colonies with "flux" Fs, an index of heat exchange between a seal and its environment. Once time of day and tidal effects were accounted for, there was no evidence of a positive correlation between hauling and Fs. However, under warm summer conditions there was a steep negative relationship. This is consistent with the possibility that hauled harbour seals are vulnerable to hyperthermia due to their adaptation to an aquatic lifestyle; the same blubber layer which keeps them warm when immersed may make it difficult for them to lose excess heat when on land. This was confirmed by a series of controlled experiments. Captive seals overheated when exposed to a radiant thermal environment similar to that in which wild animals stopped hauling. These data allowed me to derive an equation which described the rate of change in a seal's core temperature as a function of both present core temperature and Fs. I incorporated this function into a simulation model which described hauling behaviour in terms of a foraging/predator-avoidance tradeoff. The model performed well when used to predict the haul out durations of a sample of wild radio-tagged harbour seals in a known thermal environment. However, it is apparent that the processes which constrain hauling in this species are somewhat better understood than those which presumably cause it. An understanding of the foraging efficiency of harbour seals throughout the day, and of the predation risks they face, is probably fundamental to an understanding of hauling; yet these issues remain virtually unexplored. / Science, Faculty of / Zoology, Department of / Graduate
26

Incidental capture of harbour porpoise, Phocoena phocoena, in three gillnet fisheries of the northwest Atlantic : an investigation of possible factors /

Hood, Catherine Catania, January 2001 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 279-295.
27

Anthropogenic influence on the sedimentary regime of an urban estuary - Boston Harbor

Fitzgerald, Michael Gerard January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 234-241. / by Michael G. Fitzgerald. / Ph.D.
28

Demography and breeding phenology of a marine top predator

Cordes, Line Søltoft January 2011 (has links)
Worldwide harbour seal populations are showing differing and fluctuating trends in abundance, but the drivers of change remain uncertain. Within the Moray Firth, NE Scotland, count surveys carried out over the last 20 years highlighted the development of a new breeding site, providing a unique opportunity to carry out an individual-based study of harbour seal demography and pupping phenology using photo-identification techniques within a mark-recapture framework. Sightings of individual seals suggested that a large proportion of harbour seals are year-round residents at haul-out sites. Both sexes displayed high levels of between-year breeding site fidelity as well as seasonal variation in their haul-out behaviour. Apparent sex-specific survival rates (0.89♂, 0.97♀) and birth rates (0.88) were high. There was a strong correlation between lactation durations and the timing of pupping, suggesting that shifts in pupping phenology are a result of energetic constraints. This highlights the potential for using the timing of pupping as an indicator of ecosystem conditions. This study provided the first concurrent real-time estimates of survival and fecundity in a naturally regulated population of harbour seals. Demographic parameters and physiological responses indicate that prevailing conditions within the Moray Firth are favourable, and that this population should be recovering. However, observed patterns may also be an artefact of the long-term decline having caused an increase in per capita food availability through the reduction in intra-specific competition. This study highlights the current and long-term importance of individual-based data in understanding population dynamics. Through the identification of sentinel sites around the world, harbour seals could provide a single-species indicator of coastal ecosystem conditions in the Northern Hemisphere.
29

Vivre et travailler dans les ports de Gaule Narbonnaise : recherches sur le mobilier découvert en contexte portuaire ( Ier s. av. J.-C.-VIIe s.apr.J.-C.) / Live and work in the harbors of Narbonensis : research on material discovered in a harbor's context (1st century BC - 7th century AD).

Doniga, Aline 08 December 2017 (has links)
Cette thèse vise à appréhender l’ensemble de la société portuaire à travers le mobilier présent, de possibles spécificités suivant les contextes portuaires de la Narbonnaise, d’en étudier la population, l’économie et l’activité plus ou moins importante. Enfin, permet-elle de différencier un site portuaire de celui d’un site urbain ou rural ? Mon travail porte sur l’abondant matériel inédit mis au jour dans cinq ports, complété par une étude instrumentum publiée. Suite à l’analyse, des tendances se dégagent. Elles déterminent une hiérarchisation économique des ports. Cette recherche permet de percevoir toutes les strates sociales, ainsi que la présence de groupes religieux ou de corporations. La confrontation avec les sites urbains et ruraux met en évidence des spécificités propres à la nature d’un site portuaire. Les résultats témoignent du rôle d’interface des ports entre sites ruraux et centres urbains, ainsi que de leur place prépondérante dans le grand commerce. Ce travail met également en avant la diversité des activités de production au sein des ports, contrairement aux autres types de contextes. Il montre également l’importance quantitative de l’instrumentum mis au jour. Enfin, cette thèse souligne un nouvel apport de l’étude instrumentum qui permet de caractériser la nature d’un site. Toutefois, l’enrichissement des données demeure nécessaire pour confirmer ces tendances. À l’issue de cette thèse, je peux affirmer que l’instrumentum constitue le témoin majeur du « vivre et travailler » dans des lieux d’intense activité tels que les ports. L’instrumentum constitue alors un atout qui ne peut être négligé dans la connaissance de la société romaine. / This thesis aims at understanding the whole society of the harbors through the discovered items, possible specificities according to the port’s contexts of the Narbonensis, to study the population, the economy and the more or less important activity. Finally, does it make it possible to differentiate a harbor from an urban or rural site? My work focuses on the abundant unpublished material uncovered in five harbors, complemented by a published instrumentum study. Following the analysis, trends emerge. They determine an economic hierarchy of harbors. This research makes it possible to perceive all the social strata, as well as the presence of religious groups or corporations. The confrontation with urban and rural sites highlights specifics characteristics to the nature of a harbor site. The results demonstrate the interface between ports and rural and urban centers, as well as their preponderance place in the trade. This work also highlights the diversity of production activities in the ports, unlike other types of contexts. It also shows the quantitative importance of the instrumentum uncovered. Finally, this thesis emphasizes a new contribution of the instrumentum study which makes it possible to characterize the nature of a site. However, data enrichment remains necessary to confirm these trends. At the end of this thesis, I can affirm that the instrumentum constitutes the major witness of "living and working" in places of intense activity such as harbors. Then, the instrumentum constitutes an asset which can not be neglected in the knowledge of the Roman’s society.
30

Three Dimensional Mammalian Skull Morphology

Krippaehne, Suzanne Louise 09 March 1992 (has links)
This thesis deals with archiving morphological data utilizing a three dimensional coordinate system. Morphological reference points are archived via rectangular position coordinates, rectangular position vectors, and spherical position vectors. The concepts of translation trajectories, translation vectors, and relative position vectors are developed. Analysis of three dimensional coordinate data utilizing translation trajectories and translation vectors is described. In order to test the methodology developed, the method is applied to an analysis of harbor porpoise, Phocoena phocoena L., skull morphology. (Key words: morphology, ontogenetic trajectories, allometry, position coordinates, position vectors, translation trajectories, translation vectors, relative position vectors, and harbor porpoise).

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