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Fish Bulletin No. 118. California Abalones, Family Haliotidae


Abalones provide a unique fishery in California. It is the only fishery in which the fishermen use diving gear and the catch cannot be exported. Because they are taken both by sportsmen and commercial fishermen, abalones have almost always attracted considerable attention and interest. A lack of early life history and other quantitative information has caused almost continuous dispute between the sport and commercial fisheries. Several previous abalone studies were concerned primarily with the early fishery and fishing methods or discussed nomenclature and geographical distribution. Limited biological studies yielded inaccurate conclusions because of insufficient data.

In 1939, the commercial abalone industry was asked to offer suggestions for regulating the fishery, and a crew supervised by a Fish and Game biologist surveyed the coastline from Monterey to San Miguel Island. Thirty-four dives were made and 16 1/2 hours were spent on the bottom; however, this survey (Bonnot, 1940) and others (Bonnot, 1948) failed to provide an answer to the question, "What is the effect of the commercial offshore fishery on the shoreside sportfishery?" In an attempt to obtain the answer, the State Legislature directed the Department of Fish and Game to set up an abalone program and solve the dispute once and for all. In 1951, the Department launched a full-scale investigation with two vessels and a diving crew. The untimely death in August 1951 of Paul Bonnot, who had been assigned to head the investigation, was a serious setback. It was necessary for a new biologist (me) to take over and start from the bottom. Since I had no previous diving experience, I had to undergo training so I could handle myself safely underwater.

With the exception of Bonnot's underwater experiences, almost all previous observations had been made from the littoral zone. It was decided that this investigation would concentrate on the underwater aspects of the problem and most effort was directed toward fulfilling this objective. Over 1,500 hours were logged underwater by the project's divers during the investigation. Considerable new information was gathered and this report contains many of our findings.

It is my intent in this paper to provide not only the specific information requested by the State Legislature but, as far as is practical, to present as much additional information as seems appropriate and of interest.

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