Great Lakes Fish Tag and Recovery Laboratory
Begins 2014 Chinook Salmon Tagging
BY ALLEN LANE, GREEN BAY FWCO
In early March, the Great Lakes Fish Tag and Recovery Laboratory, located at the Green Bay Fish and Wildlife Conservation Office, began marking and coded wire tagging (CWT) Chinook salmon. Over the next two months, the biologists from the lab will travel to seven state operated hatcheries in Illinois, Indiana, Michigan, and Wisconsin. About 2.4 million Chinook salmon destined for Lake Michigan and Huron will be tagged and marked (Table 1). Each salmon will receive a 1-mm coded wire tag made of stainless steel and injected into the snout prior to release into the Great Lakes. Each tag has a six digit numerical code that allows fish to be traced back to a hatchery, stocking location, and year class. Along with the CWT, the fish is marked by removing its adipose fin. Removing the fin allows anglers and technicians to identify the fish as one that may contain a CWT.
The snouts of fish containing a CWT are sent to the lab in Green Bay to be extracted and read. Since 2010, nearly 13 million Chinook salmon have been tagged and marked, and when recovered, provide state agencies with an understanding of the levels of natural reproduction, post release survival, movement within and between Lake Michigan and Huron, interjurisdictional contributions to the creel, evaluation of stocking locations, and hatchery performance.