The Study of Fish Tagging for Coastal Fisheries Management

By Frank Sargeant.

Fish tagging is a powerful tool for the study of fish in coastal fisheries management where ever it’s used, allowing fishery scientists and fishery managers to keep tabs on the growth, mobility and to some extent the mortality rate of various fish.

When anglers recapture a tagged fish and report the info, researchers can track the movement of the fish and also see how much it has grown during from the time when it was tagged to get an idea of the general growth rate of that species of fish in that given estuary.

The rate of tag return also gives fishery managers some idea of fishing pressure and angler success—if all the fish that are tagged are re-caught, it’s likely fishing pressure is so high that management measures will be needed, while if only a few are re-caught, assuming good survival rates after tagging, it’s likely the fishery does not need restrictions.

Seasonal migrations can also be tracked—overall, tagging gives fishery managers some important tools to manage fish populations.

Keys To Successful Tagging in the Study of Fish

The process of tagging and the tag itself shouldn’t influence the fish’s behavior or increase its chances of dying from handling or predators, of course. Also, the tag needs to stay put in the fish. Good tags and proper tagging methods avoid these issues for the most part, researchers tell us.

Captain Richard Rutland, a Mobile Bay guide who helped researchers get the current Alabama inshore tagging program supported funded by the Coastal Conservation Association of Alabama (CCA-Alabama) underway, says successful tagging depends on preparation and working quickly to tag and release each fish. (Rutland is consistently the top tagger in the program, it should be noted.)