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dc.contributor.advisorMaughan, O. Eugeneen_US
dc.contributor.authorVillegas, Selso Valenzuela, 1952-*
dc.creatorVillegas, Selso Valenzuela, 1952-en_US
dc.date.accessioned2013-05-16T09:21:43Z
dc.date.available2013-05-16T09:21:43Z
dc.date.issued1993en_US
dc.identifier.urihttp://hdl.handle.net/10150/291362
dc.description.abstractA reported decline in Arctic grayling (Thymallus arcticus) caused the Alaskan State Board of Fisheries to close sport grayling fishing at the Ugashik Narrows, Alaska, in 1990. Sport fishing did not appear to have caused the reported decline; the decline occurred during a period with negligible harvest (Meyer 1990). My objective was to evaluate whether the decline might be an artifact associated with fish movements. I determined locational fidelity between years and persistence of occupation of individual areas and grayling population structure over time. Changes in population structure are circumstantial evidence that movement is occurring. The following factors may effect population parameters: (1) the movement of grayling into and out of the Narrows and (2) periodic displacement of grayling from the Narrows during spawning and migration of sockeye salmon (Oncorhynchus nerka). Therefore, a single sampling effort may seriously underestimate the population.
dc.language.isoen_USen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectBiology, Zoology.en_US
dc.subjectAgriculture, Fisheries and Aquaculture.en_US
dc.titleArctic grayling in the Ugashik drainageen_US
dc.typetexten_US
dc.typeThesis-Reproduction (electronic)en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.levelmastersen_US
dc.identifier.proquest1352389en_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineRenewable Natural Resourcesen_US
thesis.degree.nameM.S.en_US
dc.identifier.bibrecord.b27056491en_US
refterms.dateFOA2018-08-29T23:12:33Z
html.description.abstractA reported decline in Arctic grayling (Thymallus arcticus) caused the Alaskan State Board of Fisheries to close sport grayling fishing at the Ugashik Narrows, Alaska, in 1990. Sport fishing did not appear to have caused the reported decline; the decline occurred during a period with negligible harvest (Meyer 1990). My objective was to evaluate whether the decline might be an artifact associated with fish movements. I determined locational fidelity between years and persistence of occupation of individual areas and grayling population structure over time. Changes in population structure are circumstantial evidence that movement is occurring. The following factors may effect population parameters: (1) the movement of grayling into and out of the Narrows and (2) periodic displacement of grayling from the Narrows during spawning and migration of sockeye salmon (Oncorhynchus nerka). Therefore, a single sampling effort may seriously underestimate the population.


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