For example, young or small adult sharks cannot handle tags designed for larger, tougher animals. Sharks are tagged at the base of their first dorsal fin. The most frequently used tag for sharks is the Dart Tag which has a small dart connected to a cord about 8 inches long. Contact information and instructions for the person who recaptures the shark are printed on the cord. Sonic or radio tags are sometimes used as a way to track sharks continuously by sound, but these are expensive and only used in special studies.
Casey tags are similar to dart tags except that they have a larger barb at the end.
These tags are used less frequently than dart tags, and only for very large sharks. Very large sharks that cannot be brought on board a boat are tagged using a pole, which attaches the tag to the shark s first dorsal fin. Roto tags are an older design, less effective than dart tags and used rarely, since they are more awkward and bulky than dart tags.