• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 241
  • 13
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 4
  • 3
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 318
  • 318
  • 118
  • 70
  • 50
  • 49
  • 47
  • 46
  • 41
  • 40
  • 36
  • 31
  • 31
  • 25
  • 24
  • 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.
61

Contributory studies to the development, validation and field use of a telemetry system to monitor ventilation and trophic activity in wild Brown Trout

Oswald, Robert Leslie January 1980 (has links)
This work was performed as part of a major research project into the evaluation of the ecology of lake dwelling Brown Trout, Salmo trutta L. using ultrasonic biotelemetry techniques. The supplementary research results. leading up to and after the execution of a program of experiments involving the telemetry of feeding and ventilatory rhythms are described: 1. The presence of red (slow) fibres in the adductor mandibulae muscle of Brown Trout was confirmed to be as previously described in the Rainbow Trout, Sälmo gairdneri Richardson and other salmonids. 2. By electromyographic (EMG) and pharmacological means, the red fibres in the a. mandibulae were shown to be active during ventilation and the mosaic fibres comprising the bulk of the muscle were recruited during more dynamic events such as feeding and coughing. Observations were made on the innervation of the red fibres. 3. Comparative investigations made at sea on large deep sea Squaloid and Galeoid sharks (which have a simple adductor muscle like the Trout) showed an identical functional differentiation as obtained in the Trout. 4. The presence of a migratory 'pace setter potential' was found for the first time in Fish. Its use as an indicator of feeding activity by telemetry was rejected on practical grounds. ýýY NO 5. An ultrasonic transmitter was developed to telemeter an analogue of the adductor mandibulae EMG from wild Brown Trout, using a novel electrode design. Four fish were so equipped and released into Airthrey Loch, University of Stirling and tracked for up to 24 hours (following a 24 hr allowance for post-anaesthetic recovery). Feeding and ventilatory periodicity, linear and angular movement patterns and photoperiod were intercorrelated. Angle of turn and subsequent step length were positively correlated and feeding activity was marked by a preference for dextral turning. 'Area restricted searching' and 'area avoided searching' were the probable causes of the movement patterns seen in this and previous investigations at Airthrey Loch. A depth preference and orientation of the fish to topography was demonstrated. Following analysis of the angle of turn and step length data, it was concluded that the larger transmitter package and more severe surgery materially affected the fishes' behaviour relative to data previously obtained at Airthrey Loch using smaller transmitters. 6. Due to difficulties experienced in 5 above due to an unsuspected effect on the a. mandibulae EMG detectable up to 24 hrs post-anaesthesia, a frequency analysis was made of the a. mandibulae EMG of the Brown Trout and several other species. This disclosed that the EMG from red fibres has a frequency spectrum considerably lower than that of 'standard' mammalian muscle. The progressive failure of the EMG transmitter with time was due to a combination of the anaesthetic effect and the frequency spectrum relative to certain design features. In the light of these observations, subsequent designs of the EMG transmitter were able to take this into account.
62

Sustainability indicators in marine capture fisheries /

Potts, Tavis William. January 2004 (has links)
Thesis (Ph.D.)--University of Tasmania, 2004. / For consultation only. No copying permitted until 13-3-2006. Includes bibliographical references.
63

An evaluation of walleye (Sander vitreus) spawning potential in a north temperate Wisconsin lake /

Williamson, Lauren E. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2008. / Submitted in partial fulfillment of the requirements for the degree of Master of Science in Natural Resources (Fisheries), College of Natural Resources. Includes bibliographical references (leaves 82-89).
64

A conceptual and operational understanding of social resilience in a primary resource industry : insights for optimizing social and environmental outcomes in the management of Queensland's commercial fishing industry /

Marshall, Nadine A. January 2006 (has links)
Thesis (Ph.D.) - James Cook University, 2006. / Typescript (photocopy) Bibliography: leaves 172-207.
65

Stock structure of a coral reef fish, Plectropomus leopardus : identification and implication for harvest strategy evaluation /

Bergenius, Mikaela Annika Johansdotter. January 2007 (has links)
Thesis (Ph.D.) - James Cook University, 2007. / Typescript (photocopy) Bibliography: leaves 154-165.
66

The croaker fishery and dried swimbladder trade in Hong Kong, and the reproductive biology of the greyfin croaker, Pennahia Anea

Tuuli, Cynthia Darta. January 2010 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 159-171). Also available in print.
67

The economic consequences of fish habitat conservation and management /

Upton, Harold F. January 2004 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2004. / Typescript. Includes bibliographical references (leaves 217-223).
68

An evaluation of catchability and changes in seasonal catch rates of five Wisconsin game fishes /

Schoenebeck, Casey Walter. January 2004 (has links) (PDF)
Thesis (M.S.), Natural Resources / Fisheries, University of Wisconsin--Stevens Point, 2004. / Includes bibliographical references (leaves 53-58).
69

The influence of individual transferable quotas on discarding and fishing behavior in multispecies fisheries /

Branch, Trevor A. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 153-165).
70

Uncertainty in the management of activities affecting marine mammal populations : the tuna-dolphin conflict, a case study /

Alvarez-Flores, Carlos M., January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 146-157).

Page generated in 0.0989 seconds