Other static tagging techniques currently under investigation include the use of laser beams to apply small brands and the use of gas branding devices. Neither technique, however, has yet reached the field biologist.
The success of any tagging program using static tags depends on the resighting of tagged animals and the recovery of tags. For that reason, we appeal to readers to be on the lookout for tagged animals and to report sightings to one of the authors.
[Illustration: Appendix Figure A1.--Some of the basic kinds of tags used to mark porpoises, dolphins, and small whales. A, B, and C are nylon button tags, which are placed in the dorsal fin of animals and may be clearly visible as the animal surfaces to breathe. D is a vinyl spaghetti tag. (_Photo by R. Krenic, courtesy of Naval Undersea Center._)]
[Illustration: Appendix Figure A2.--A spaghetti tag in the back of a blue whale off San Clemente Island, Calif. (_Photo by S. Leatherwood._)]
[Illustration: Appendix Figure A3.--A spaghetti tag in the flank of a bottlenosed dolphin off Loreto, Baja California, Mexico. This particular tag was placed unusually low. The streamer and spaghetti tags are usually placed high on the back, just in front of the dorsal fin, and are clearly visible as the animal surfaces to breathe. (_Photo by W. E. Evans._)]
[Illustration: Appendix Figure A4.--A button tag placed on the dorsal fin of a newly captured saddleback dolphin off Catalina Island, Calif. (_Photo by W. E. Evans._)]
[Illustration: Appendix Figure A5.--This is the way the button tag appears on an animal swimming free in the open sea off Palos Verdes, Calif. (_Photo by B. Noble, courtesy of Marineland of the Pacific._)]
[Illustration: Appendix Figure A6.--Freeze-branding is an apparently painless method of applying a permanent identifying mark to the body of a porpoise or whale. (_Photo of a bottlenosed dolphin off Sarasota, Fla., by A. B. Irvine._)]
In recent years, radio transmitter tags have been developed for use on marine mammals. As they continue to become more reliable, these tags are expected to come into more and more widespread use.
Early radio tags (Fig. A7) were simple locator beacons which permitted the animal to be tracked by sending a signal to a tracking vessel or aircraft every time the animal surfaced and the antenna tip was exposed. Even these basic packages provide important information on movement, activity patterns, and respiration rates.