| Summary: | This dataset contains the short-term survival and tag loss data from tagging of juvenile pink salmon with passive integrated transpondar (PIT) tags in southwestern Prince William Sound, Alaska. The catch data is referenced by date, time of day, latitude and longitude. This was a feasibility study and contains catch data from 1 purse seine set on 1 day. This is the only test of the mortality of juvenile pink salmon captured in the marine environment and tagged with PIT tags documented in the primary or gray literature as of 2005. The goal of this project was to evaluate the use of PIT tags as a second mark on otolith thermal marked juvenile hatchery pink salmon. The mortality could then be evaluated separately for early marine and the open ocean phases of the pink salmon life cycle. Also included are water temperature and slainity data for the water in which the juvenile pink salmon were held during the short term mortality test. Data on tag detection in a adult pink salmon in a processing plant and detector configurations are also included. The fish were captured on 7/6/2005 at 17:51 GMT and tagging was complete by 01:59 on 7/7/2005 GMT. The fish were held on board the ADFG vessel R/V Solstice in an insulated fish tote until the study ended after 96 hours (7/11/2005 @ 02:00 GMT). Survival to 96 hours was 92.5% (185 of 200), but 2 more fish had injuries that would have caused mortality. A lack of tagging experience probably increased the mortality because 6 of 15 mortalities were in the first 25 fish tagged. Examination of processing plants in Cordova for locations to scan for tags in returning adult pink salmon indicated that changes in the plant would be necessary to get acceptable detection probabilities. Detection tests in August 2005 at one processing plant in Cordova supported that assessment. Detection probabilities from three tests (n=51 tagged fish) were 0.14, 0.24, and 0.06. Changes to processing lines to reduce the amount of metal would be required to get acceptable detection rates. The Exxon Valdez Trustee Council provided most of the funding for this project. The Alaska Department of Fish and Game contrbuted a significant amount of vessel time and PIT tag readers and data loggers (Mark Williette in the Soldotna office). The United States Forest Service (Dirk Lang) also loaned a portable PIT tag reader.
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