Spedicato, M.T.; Lembo, G.; Marmulla, G. (eds.) 275 Aquatic telemetry: advances and applications. Proceedings of the Fifth Conference on Fish Telemetry held in Europe. Ustica, Italy, 9-13 June 2003. Rome, FAO/COISPA. 2005. 295p. Comparison of acoustic and PIT tagged juvenile Chinook, Steelhead and Sockeye Salmon (Oncorhynchus, spp.) passing dams on the Columbia River, USA T.W. Steig*1, J.R. Skalski2, and B.H. Ransom1 1Hydroacoustic Technology, Inc. 715 N.E. Northlake Way, Seattle, WA 98105 U.S.A. Tel.: (206) 633-3383; Fax: (206) 633- 5912. *Correspondig Author, e-mail:
[email protected] 2Columbia Basin Research, School of Aquatic and Fishery Sciences, University of Washington Seattle, WA, U.S.A. Key words: acoustic tags, PIT tags, fish behaviour, fish movement, salmon smolt survival. Abstract The purpose of the study was to compare migration behaviour and survival of acoustic and passive integrated transponder (PIT) tagged juvenile salmonids passing dams on the Columbia River, Washington State, USA. Downstream migrating yearling chinook (Oncorhynchus tshawytscha Walbaum 1792), steelhead (Oncorhynchus mykiss Walbaum 1792), sockeye (Oncorhynchus nerka Walbaum 1792), and sub-yearling chinook smolts were individually implanted with either acoustic or PIT tags and monitored at Rocky Reach and Rock Island dams dur- ing spring and summer 2002. Travel times and detection rates were compared for acoustic (“A” tag weight 1.0 g and “E” tag weight 1.5 g) and PIT (tag weight 0.06 g) tagged fish released upstream of Rocky Reach Dam and detected at a Surface Collector Bypass Channel and further downstream at the Rock Island Dam project.