|Document Type:||Contract Report|
|Title:||An assessment of freeze–brand and PIT–tag recovery data for juvenile salmonids at McNary Dam, 1988|
|Author/Editor:||Clinton Scott McCutcheon, Albert E. Giorgi|
|Publisher:||National Marine Fisheries Service|
|Contracting Agency:||Bonneville Power Administration. Portland, Oregon|
This study evaluated mark recovery data from PIT–tagged and freeze–branded river–run yearling and subyearling chinook salmon (Oncorhynchus tshawytscha), sockeye salmon (O. nerka), and steelhead (O. mykiss) at McNary Dam in 1988. Double–marked (PIT–tagged and freeze–branded) juvenile salmonids were released within the McNary Dam collection system upstream from the PIT–tag detectors and brand–sampling system. Results indicate that brands were recovered in smaller proportions than PIT tags, and the variability of brand data was considerable. Most of the error associated with brands was attributable to human error inherent in brand detection and interpretation.