Coded Wire Tags (CWT)

Poster: Coded Wire Tags

Coded Wire Tags poster

Coded Wire Tag in fish

Coded Wire Tag in fish

Clipped Adipose Fin

Clipped Adipose Fin

You can help in the monitoring of Great Lakes salmon and trout populations. Many of these fish have been marked with a small coded-wire tag, which is implanted in the head of the fish, but invisible to the naked eye.

If you catch a fish that is missing only the adipose fin (see photo, above), it is possible that it has had a coded-wire tag implanted into its snout. Please record the following information: date caught, location caught, species, length, weight, sex (if possible) and fin clip. The data obtained can be recorded on the coded wire tag recovery form.

Remove and freeze the fish's snout (part of head from behind the eyes forward), and drop off the snout along with data sheet at a drop of location, or call 517-284-5830 for a list of local sites. Please do not mail! If a tag is extracted, the fishermen will be notified of the age and stocking location of their catch.

CWT recovery form »

Drop off locations »

Additional Information about CWT:

Other Links:

Stocking Information from the Great Lakes Fish Stocking Database

Adlerstein et al. 2007. Lake Trout Movements in US Waters of Lake Huron Interpreted from Coded Wire Tag Recoveries in Recreational Fisheries

Adlerstein et al. 2007. Estimating Seasonal Movements of Chinook Salmon in Lake Huron from Efficiency Analysis of Coded Wire Tag Recoveries in Recreational Fisheries

Chinook Life History, Stocking Methods, and Post-Stocking Survival in Lake Huron