Empirically, squid is the best Dungeness crab bait.
Squid: A History
In the 1950’s, squid became one of the most commonly used Dungeness crab baits along the Oregon coast.
Cockles (Cardium corbis), razor clams (Siliqua patula), and other miscellaneous clams as well as herring (Clupea pallasii) were used for bait during the early years of the fishery. Squid (Loligo sp.), imported from California, and razor clams are at present the most commonly used bait along the Oregon coast. Some work has been done to develop an effective artificial bait, although to date a satisfactory product has not been produced.
In a 1975 research paper, Dungeness crabs exhibited the strongest response to whole squid compared to artificial test compounds. Interestingly, Pro-Cure Crab and Shrimp Attractant (“a blend of potent fish oils, salmon egg oil, amino acids and a touch of anise”) is essentially a mix of everything tested in 1975.
It must be noted that none of the test compounds or extracts approximated whole squid in chemattractant potency. Admittedly, many other compounds might have been tested. There is evidence, however, to indicate that decapod crustaceans determine the attractancy of food by a complex of chemical signals. Shelton and Mackie (1971) prepared a synthetic mixture of chemicals based on the composition of the clam Tapes japonica. None of the major components of this mixture when tested alone was as effective as the complete mixture in attracting the shore crab Caroinus maenus.
Squid: The Modern Bait
Squid continues to be the most commonly used bait by commercial fishers. Over one million pounds of squid are used as crab bait by Oregon fishermen every year!
Today, many types of bait are used to attract crab. Bait use estimates for the ocean commercial fishery derived from logbook information indicate that squid are the most used bait species, followed by clams and sardines (Figure 34).
A survey of Oregon commercial fishermen found 100% of them used squid as bait, although the sample size (N=24) was small . Twenty of those fishermen ranked effectiveness as the most important factor when choosing bait. Thus, we can infer fishermen use squid because it is effective.
Within the group of twenty-four fishermen interviewed, the three most common bait types were squid, rockfish, and razor clams. 100% of the fishermen used squid, 87.5% used rockfish, and 75% used razor clams.
When asked to rank effectiveness, availability, and cost in terms of strongest to weakest determinants influencing bait choice, 83% placed effectiveness as the most influential factor. They indicated that despite the high price of bait, the expense of preferred bait is worthwhile if it leads to higher catch. Availability and cost were evenly split as the second strongest motivators, while cost was the most frequent third choice.
Conclusion
Squid has stood the test of time as the single best Dungeness crab bait. Of course, squid can be supplemented with other baits (e.g. clams, sardines, mackerel)) or artificial attractants. Further research is needed to explain why Dungeness crabs exhibit such a strong preference for squid.