Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"gear type"”.
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Bycatch of the Lake Pontchartrain Basin inshore shrimp fishery and its effect on two sea catfish species: the gafftopsail catfish (Bagre marinus) and the hardhead catfish (Ariopsis felis)
… differences in size-class distributions by gear type using density kernel plots and Mann-Whitney U tests. The two gear types collected significantly different assemblages (ANOSIM R = 0.522, p = 0.001) and gear type explained more composition differences than other factors such as month, …
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The bottom longline fishery and its use as a source of benthic biodiversity information around South Georgia
… too steep or rough for most scientific sampling gear. This thesis investigates the potential for this fishery to be a source of much needed biodiversity information and evaluates how benthic invertebrate bycatch data is collected by fishing observers. After a general introduction, chapter 2 …
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Flood pulse influences on exploited fish populations of the Central Amazon
… were modeled as a function of fishing effort, gear type, seasonal flood pulse variables, and interannual flood pulse variables. These models were analyzed to understand which flood pulse variables had the strongest relationships to catches, and evaluate different flood pulse influences among …
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Fish and decapod community structure in estuarine habitats of the New Orleans Land Bridge, including a description of the life cycle of tarpon (Megalops atlanticus) in southeastern Louisiana
… habitats was difficult. The cast net is a useful gear type for this type of sampling and can be readily standardized for each operator. Standardization of the area covered by the net allows density of collected nekton to be calculated. Little is known about the life cycle of one important …
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Ecosystem impacts of intertidal invertebrate harvesting: from benthic habitats to bird predators.
… of key invertebrate prey groups to different gear types used in different intertidal habitats. Hand gathering most severely reduces prey abundance, which is likely to be due to the accuracy of harvesting with these gear types, while recovery trends vary between different combinations of gear …
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The effects of escape panels on commercial catches of juvenile hakes (Merluccius spp.) off South Africa
… hake during the experiment. When the different gear types were compared with the controls using a normal approximation of a chi-square test, there were no significant differences in the proportions of small hake caught (square mesh, p = 0.4344; large mesh, proportion increased and plastic grid, …
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The Impact of Fishing on Populations of Deep-water Chondrichthyan Fishes of the Northeast Atlantic
… squamosus and Chimaera monstrosa by decade and gear type, suggesting that these species may be some of the most vulnerable deep-water chondrichthyans when faced with intensive commercial fishing. Nevertheless data used in multivariate models were fragmentary and unbalanced in nature, and …
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Movement of Selected Nearshore Temperate Reef Fishes Along California's Central Coast
… geographic variation, source of recapture data, gear type, days at liberty, length, initial capture depth, handling condition, and fish density. Additionally, the applicability of tag-and-recapture methodology is examined as an effective source of fish movement information. The results of this …
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Conserving dolphins and fishermen: Combining science and local knowledge to reduce cetacean bycatch
… globally, and it occurs in nearly every fishing gear type. Despite its widespread occurrence, observations of bycatch are rare, and scientific data on marine mammal bycatch are limited. Difficulties result in developing models that accurately depict the interactions. This study focuses on …
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A Comparison Between South Dakota and North American Standard Sampling Gears in Lakes and Reservoirs
<p>A statewide gear comparison was performed in South Dakota during 2013 and 2014 between current South Dakota Department of Game, Fish and Parks (SDGFP) sampling gears (i.e., gill nets and modified fyke nets) and their equivalents described in <em>Standard Methods for Sampling North American …