A 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.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/291362 |
| Date | January 1993 |
| Creators | Villegas, Selso Valenzuela, 1952- |
| Contributors | Maughan, O. Eugene |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Thesis-Reproduction (electronic) |
| Rights | Copyright © 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. |
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