Tagged Animals

If your vessel encounters a tagged fish, marine mammal, or sea turtle, please make every effort to recover the tag (if the fish is dead) or record the information in it (e.g., for a tagged turtle that will be released). In most cases, instructions on where to report recaptures appear on the tag. With these types of tags, there is often a reward associated with the returning the tag to the researchers who deployed it. Generally, the date, location, animal’s length (and sex when it is noticeable), and fishing conditions should be reported. Your observer program can provide specific recovery information for the tags likely to be encountered in your region. This is valuable data used in fisheries management decisions, stock assessments, and other biological research.

Tag types. There are a variety of tag types in use, from simple numbered plastic tags to complex electronic tags. Plastic spaghetti or dart tags are attached on the back of the fish. Rototags are a two-piece, plastic cattle ear tag, which is inserted through the first dorsal fin. Sonic tags are miniature radio transmitting devices that are surgically implanted inside the tuna. Since sonic tags are not visible externally, a conventional tag of a certain color will be visible on the outside. Internal archival tags, implanted in the body cavity, record the internal body temperature and the environment’s temperature, pressure, and light. Smart Position or Temperature Transmitting (SPOT) tags are attached to the animal’s dorsal fin and this tag sends a signal to a satellite every time the animal surfaces. Pop-up Satellite Archival Tags (PSAT) are inserted with an anchor and a tether into the dorsal musculature, recording temperature, pressure, and light, and they detach from the animal on a preprogrammed date.