Development of an Index to Bird Predation of Juvenile Salmonids within the Yakima River.

Grassley, J. M. ; Major, W. ; Ryding, K. ; Grue, C. E.

Technical Information Center Oak Ridge Tennessee

关键词: Predation;    Salmonids;    Yakima River;    Washington State;    Juveniles;   

RP-ID  :  DE2003812189

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

Avian predation of fish is suspected to contribute to the loss of juvenile spring chinook salmon in the Yakima Basin, potentially constraining natural production. In 1997 and 1998, the Yakama/Klickitat Fisheries Project (YKFP) and the Washington Department of Fish and Wildlife (WDFW)--whose goal is to increase natural production historically present within the Yakima River-- initiated investigations to assess the feasibility of developing an index to avian predation of juvenile salmon within the river. This research confirmed that Ring-billed Gulls and Common Mergansers were the primary avian predators of juvenile salmon, and that under certain conditions could impact migrating smolt populations.