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首页> 外文学位 >Juvenile life history, downstream migration rate, and survival of wild Snake River fall chinook salmon (Oncorhynchus tshawytscha).
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Juvenile life history, downstream migration rate, and survival of wild Snake River fall chinook salmon (Oncorhynchus tshawytscha).

机译：少年生活史，下游迁移率和野生蛇河秋努鲑（Oncorhynchus tshawytscha）的生存。

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摘要

Snake River fall chinook salmon Oncorhynchus tshawytscha were listed for protection under the Endangered Species Act in 1992. In 1992, there was little information on life history, downstream migration rate, or survival of young fall chinook salmon in the former and current spawning and rearing areas. There was also little information on the efficacy of summer flow augmentation, which was intended to improve downstream migration rate and survival of fall chinook salmon smolts in the lower Snake River. In this dissertation, I analyzed data collected on wild Snake River fall chinook salmon from 1992 to 2000 to provide the above information.; I found that development through the early life stages (fry, parr, and smolt) proceeded in direct accordance with the water temperatures of present-day spawning and rearing areas. Wild fall chinook salmon emerged, reared along the shorelines, and began seaward migration earliest in the warmest spawning and rearing area, and latest in the coolest area. The historical spawning and rearing area, which was eliminated by dam construction, was warmer than present-day areas. Therefore, I believe it produced young fall chinook salmon that developed on an earlier time schedule than observed in the spawning and rearing areas currently available for production.; I found that downstream migration rate of wild fall chinook salmon was influenced by several variables. Larger juveniles migrated downstream faster than smaller juveniles. Fish that were initially captured, tagged, and released at warmer temperatures typically migrated downstream faster than those released at cooler temperatures. Fish that passed downstream during periods of higher flow usually migrated faster than fish that experienced lower flow levels. Downstream migration rate also increased as the distance traveled in free-flowing river increased.; I found that survival of wild fall chinook salmon during early seaward migration was influenced by both flow and water temperature. Survival increased as flow during downstream passage increased. Smolts that migrated downstream when temperatures were relatively cool survived better than those that migrated when temperatures were relatively warm.; I developed modeling techniques to estimate the effects of summer flow augmentation on downstream migration rate and survival of wild juvenile fall chinook salmon. Model runs suggested that the increases in flow caused by summer flow augmentation increased downstream migration rate. Model runs also indicated that increases in flow and decreases in water temperature caused by summer flow augmentation increased smolt survival during early seaward migration.
机译：根据1992年《濒危物种法》，Snake River秋季奇努克鲑鱼（italic> Oncorhynchus tshawytscha

著录项

  • 作者

    Connor, William Paul.;

  • 作者单位

    University of Idaho.;

  • 授予单位 University of Idaho.;
  • 学科 Agriculture Fisheries and Aquaculture.; Biology Zoology.
  • 学位 Ph.D.
  • 年度 2001
  • 页码 p.4288
  • 总页数 130
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 水产、渔业;
  • 关键词

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