Cooperative Shark Tagging Study off the Pacific Coast of Mexico

摘要

The report is concerned solely with the shark-tagging cruise undertaken November 1-December 30, 1964. This study was undertaken to gain knowledge about the migration and growth rates of some eastern Pacific sharks by means of tagging, with a corrolary objective of determining which of the many types of tags are best suited for tagging sharks. Tagging efforts were concentrated on the larger species, especially those of the genus Carcharhinus. These sharks are important as commercially desirable species in Mexico, and as detrimental pests in the American and Mexican tuna, mackerel, and shrimp fisheries. The Bureau of Commercial Fisheries Tuna Resources Laboratory launched a study in 1962 to learn the causes, effects, and possible remedies to the problem of shark attacks on purse seine nets. Mexican biologists are interested in the life history of sharks because of their commercial importance. The goals of this cooperative study, then, is expected to yield information which will be of functional value as well as contributing knowledge to a little-known field of shark biology.