Accession Number : ADA581329


Title :   Adult Pacific Lamprey Migration in the Lower Columbia River: 2011 Half-Duplex Pit Tag Studies


Descriptive Note : Technical rept.


Corporate Author : NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION SEATTLE WA NORTHWEST FISHERIES SCIENCE CENTER


Personal Author(s) : Keefer, M L ; Caudill, C C ; Johnson, E L ; Clabough, T S ; Jepson, M A ; Boggs, C T ; Moser, M L


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/a581329.pdf


Report Date : Jan 2012


Pagination or Media Count : 39


Abstract : We tagged adult Pacific lamprey (Entosphenus tridentatus) collected at Bonneville Dam with half duplex (HD) passive integrated transponder (PIT) tags and monitored their passage and migration behaviors at Bonneville, The Dalles, John Day, McNary, Ice Harbor, Lower Monumental, Lower Granite, and Priest Rapids dams. Our objectives were to calculate lamprey passage times, to estimate escapement past the monitored sites, and to evaluate potential physiological and environmental correlates with lamprey migration through the study area. In total, we HD-PIT tagged 929 lampreys in 2011: 800 were released downstream from Bonneville Dam near Hamilton Island, 109 were released upstream from Bonneville Dam near Stevenson, WA, and 20 were released directly into the Cascades Island lamprey passage structure (LPS). An additional 85 lampreys were double-tagged with HD-PIT tags and acoustic transmitters (JSATS), and results from these fish are presented in a separate report. The 2011 escapement estimate from release below Bonneville Dam past the dam was 56%, higher than estimates in the 2005-2009 HD-PIT studies (41-53%). Escapement from the top of Bonneville Dam to the top The Dalles Dam (52%) and from the top of The Dalles Dam to the top of John Day Dam (80%) was also higher than or similar to previous estimates. Large lampreys in the downstream release group were significantly more likely than small lampreys to pass through most dam-to-dam reaches. As in previous years, lampreys last detected at upriver sites were significantly larger than those last recorded closer to the release site, indicating that size-dependent effects on migration distance and final distribution were likely.


Descriptors :   *ACOUSTIC TRACKING , *FISHES , *MIGRATION , COLUMBIA RIVER , DAMS


Subject Categories : Biology
      Acoustic Detection and Detectors


Distribution Statement : APPROVED FOR PUBLIC RELEASE