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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

Ascidiacea (Chordata:Tunicata) do litoral tropical brasileiro

Lotufo, Tito Monteiro da Cruz. January 2002 (has links)
Thesis (doctoral)--Universidade de São Paulo, 2002. / Title from PDF t.p. (viewed May 21, 2006). Includes bibliographical references (p. 173-183) and index.
42

Population kinetics and related ecology of the northern sea lion, Eumetopias jubatus, and the California sea lion, Zalophus californianus, along the Oregon coast

Mate, Bruce R. 03 1900 (has links)
University of Oregon theses, Dept. of Biology, Ph. D., 1973. A print copy of this title is available from University of Oregon's Oregon Institute of Marine Biology library and the Science library, under the call number: QL 737.P63 M3
43

Environmental cues and sensory preferences directing the nesting process in loggerhead turtles, caretta caretta, nesting in Maputaland, South Africa

Brazier, Wayne January 2012 (has links)
Animals use their senses for everything on an immediate, and day to day fashion – detecting danger, finding food, finding mates among other activities. In sea turtles and other migratory species senses are used for long-distance migrations. Senses such as smell, vision and hearing, have been studied experimentally under laboratory conditions but seldom have been investigated in the field. This thesis takes a combination of field and laboratory experiments and investigates some of the hypotheses involved in natal homing and nest site selection. The loggerhead’s nesting distribution in Maputaland is distinct with characteristic high and low density nesting areas which are consistent from year to year. Investigations by earlier researchers on these beaches suggested that beach characteristics, such as beach morphodynamic type and beach width, do not appear to influence the beaches at which loggerheads emerge to nest. The high density nesting area (with approximately 440 loggerhead emergences/km) have similar beach characteristics as the low density nesting area (with <50 loggerhead emergences/km). It is therefore suggested that there is another cue that drives nest site selection. It can either be related to a physical characteristic not yet realised, or is a non-physical (but chemical or biological) cue. This dissertation aims to identify the sensory inputs received during the nest selection process, as well as sea-finding ability after nesting. To investigate the mechanism causing the high-density as opposed to the low-density nesting area, three potential drivers were investigated namely: chemical imprinting (as a natal beach cue), ambient and artificial light (as deterrents) and social facilitation (as a learned behaviour). It was also attempted to identify the strength of the most common senses – vision, hearing and smell. As animal ethics restricts interfering with emerging or nesting turtles, the strengths of these senses were tested during sea-finding by adult loggerheads. The results indicate that sulfide concentrations appear to be used as chemical cues for nesting as these concentrations are elevated (>150 percent) in the high density nesting beaches compared to the low density nesting beaches within and among seasons however further investigations are required. Artificial light (range: 0.045–0.5 lux) is an active deterrent of female emergences while ambient light, even under extreme conditions such as lightning during electric storms (up to 8.2 lux), appears to have no observable influence on the spatial or temporal distributions of emergences. Social facilitation appears unlikely as a primary nest site selection factor for loggerheads. It may however, play a minor secondary role to preferred areas or hotspots. Sea-finding in post-nesting female loggerheads appears to be driven exclusively by visual cues such as the light horizon, with minimal to no influence from other cues (the sound of the breakers, slope or smell of the ocean) which solidify the visual system’s use in sea-finding. This research on the nest site selection of loggerheads and the sensory systems involved in this process has added valuable information to the limited pool of knowledge already present and has created a solid framework on which further investigations can be based. Future work in this field should focus on integrating a suite of sensory stimuli and cues to receive a greater understanding of the sensory systems used in nest site selection.
44

Effects of formulated feeds and Saccharina latissima on growth, gonadal-somatic index, and gonad color in grow-out stage green sea urchins, Strongylocentrotus droebachiensis, in land-based echiniculture /

Kling, Ashley Lindsey, January 2009 (has links)
Thesis (M.S.) in Marine Biology--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 131-136).
45

Using agent-based modeling to examine the logistical chain of the seabase /

Milton, Rebecca M. January 2004 (has links) (PDF)
Thesis (M.S. in Operations Research)--Naval Postgraduate School, March 2004. / Thesis advisor(s): Susan M. Sanchez. Includes bibliographical references (p. 61-65). Also available online.
46

Arctic sea ice dynamics : drifts and ridging in numerical models and observations = Arktische Meereisdynamik : Drift und Presseisrückenbildung in numerischen Modellen und Beobachtungsdaten /

Martin, Torge. January 2007 (has links)
Univ., Diss.--Bremen, 2007.
47

China's naval modernization and implications for the South China Sea /

Small, Page E. January 2002 (has links) (PDF)
Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, December 2002. / AD-A411 064. Includes bibliographical references (p. 71-75). Also available online.
48

China's naval modernization and implications for the South China Sea /

Small, Page E. January 2002 (has links) (PDF)
Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, December 2002. / Thesis advisor(s): H. Lyman Miller, Randall J. Hess. Includes bibliographical references (p. 71-75). Also available online.
49

In-stream behavioral responses of female sea lampreys to pheromone components

Johnson, Nicholas S. January 2008 (has links)
Thesis (Ph. D.)--Michigan State University. Dept. of Fisheries and Wildlife, 2008. / Title from PDF t.p. (viewed on Aug. 19, 2009) Includes bibliographical references. Also issued in print.
50

Monitoring, assessment, and management of the green sea urchin (Strongylocentrotus droebachiensis) fishery in Maine /

Jones, Kate, January 2006 (has links) (PDF)
Thesis (M.S.) in Marine Biology--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 83-90).

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