CALIFORNIA DEPARTMENT OF FISH AND GAMESHARK TAGGING PROGRAM SUMMARY
In 1983, The California Department of Fish and Game (CDFG) began a tagging program to collect data on local shark species. The purpose of this program was to determine migration, growth, and stock structure patterns. The program currently includes sport anglers and commercial fishermen who voluntarily tag and release sharks. While most of these anglers fish in southern California waters some fish in the Monterey and San Francisco Bay areas. New taggers are actively recruited through CDFG representation at shark fishing tournaments, sport shows, and other public events. In addition, CDFG and National Marine Fisheries Service biologists jointly conduct several research cruises annually to capture and tag sharks throughout the Southern California Bight. A newsletter is produced annually by project biologists, providing information on the tagging program, the year's results, and other new information to the volunteer taggers and the general public. Sharks are tagged at the base of their first dorsal fin using a bright yellow dart tag (Floy FH-69). Each tag is uniquely numbered and labeled with a CDFG return address. Before a tagged shark is released, the date, species, length, sex and tagging location are recorded on a card, which is returned to the Department. The reward of a CDFG Tagging Program baseball cap is given to anyone returning a tag along with information concerning the shark's movements and growth since it was tagged. This information is also sent to the person who originally tagged the recovered shark.To date over 8,500 sharks representing 17 species have been tagged. 145 of these sharks have been recaptured. In 1997, 1874 sharks were tagged and 26 recaptured (table 1). The most common sharks tagged and recaptured in California are blue sharks, and shortfin mako sharks. These sharks represent a large portion of the recreational shark fishery in California waters.Evidence has been provided through the Shark Tagging Program supporting a theory that the southern California bight (the waters between Point Conception and the Mexican border) is a nursery area for these sharks.
Table 1. Summary of tagged (T) and recaptured (R) sharks 1983-1997.
1983-96 1997 Total T R T R T R Blue Shark 5296 38 1164 4 6460 42 Shortin Mako 1427 71 655 13 2082 84 Angel Shark 107 6 0 0 107 6 Thresher Shark 69 1 7 0 76 1 Baskin Shark 57 0 0 0 57 0 Sevengill Shark 51 3 7 2 58 5 Leopard Shark 29 0 4 1 33 1 White Shark 13 0 3 0 16 0 Soupfin Shark 4 0 1 0 5 0 Spiny Dogfish 4 0 0 0 4 0 Smoothhounds 3 0 0 0 3 0 Other Species 11 0 9 0 20 0 Total: 7071 119 1850 20 8921 139 To make a tagging stick, drill a 3/16" hole to a depth of 1 " in a wood dowel (3/4" to 1 " diameter). The dowel should be 5- to 6-feet long. The tip may be epoxied directly into the hole. Another option is to obtain a threaded stainless steel insert (check you local marine hardware) that will match the threads on the tip. Epoxy the insert into the hole. The tip can then be changed as necessary.
Mount the tag on the stick as shown above. The slot in the tip is fitted onto the leading edge of the tag's dart. Attach the trailing end of the tag to the stick with a rubber band to prevent accidental loss.
Tag the shark in the musculature next to the dorsal fin, above the lateral line. Estimate the length as shown above. "Total Length'? is preferred, but fork length is also acceptable.
Determine the sex; male sharks have claspers on their pelvic fins, females do not. Note: It is difficult to see the claspers on small mako sharks, if you cannot clearly tell the sex leave that portion of the tag card blank.
Fill out and mail the tagging report card immediately. The tag is of NO VALUE unless the information is returned promptly.
