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Crowfoot Hooks for the Harvest of Freshwater Mussels

Crowfoot Hooks for the Harvest of Freshwater Mussels The historic artifacts in this photo are called “crowfoot hooks.” They were the business end of perhaps the most effective method ever developed for harvesting mussels from the Mississippi and other mussel-bearing rivers. Mussels, most commonly called “clams,” once occurred by the tens of millions in the Upper Mississippi. Early European settlers initially paid little attention to them. Then, in 1857, an outstanding pearl was found in a mussel in New Jersey and sold to Tiffany and Co. for $2,500. Later, fine pearls were also found in Ohio. Soon the “pearl rush” was on across the mussel-bearing streams of the U.S. At first, people waded the streams during low water or dove (“pollywogged”) for mussels. They brought them to shore to be opened, often by steaming on crudely made sheet-metal “cookers.” Pearl rushes came and went in various regions, and Tiffany & Co. had traveling buyers to evaluate and buy pearls. The shells were just left in heaps along the stream banks.

Then, along came a German emigrant button maker, J. F. Boepple. In 1890-91, Boepple and two other men at Muscatine, Iowa, developed machines to cut and process buttons out of Mississippi River mussel shells. Shell buttons were lustrous and very durable. To make them, you needed a lot of shells from rather thick-shelled, deep-water mussels. These mussels occurred on dense aggregates or “beds” under fairly strong current, often in water 5–10 feet deep, or more. Now that there was a market for the shells as well as the pearls, the mussels were even more desirable. But there was also a problem– how to harvest the deeper-water mussels?

Some mussels could still be collecting by wading at the lowest water levels, or by diving, but both options were poor choices for strong currents and deep water. Other methods were soon devised, but all had limitations. Rake with handles 10–15 feet long were used through the ice in winter. Another method involved a type of dredge. About 1896, the first “crowfoot bars” were developed. These metal bars 6 feet long had attached 50–100 crowfoot hooks, often with a series 4 to 8 hooks in a single string (photo, left). The hooks were attached to the bar, and the bar was attached to a line from a john boat so it could be dragged along the mussel bed. Mussels live embedded in the bottom of the river in dense beds. The individuals are oriented with the current, with their shells open a quarter-inch or less to siphon water and food in and waste out. As the crowfoot bar was dragged over the mussel bed, and the hook touched the soft tissue, the mussel closed and clamped its strong muscles on the crowfoot hook. After a short time, the crowfoot bar was pulled to the surface with a winch, and the desirable mussels were removed. The mussels were returned to shore and placed in a cooker, and the meat was then removed and searched for pearls. The empty shells were sold to one of the dozens of button factories that sprang up along the Upper Mississippi.

After a while, mussels became scarce in many parts of the Upper Mississippi, and shells were brought in by barge from some southern streams to supply the button factories. The pearl button industry slowly came to an end with the advent of plastic buttons after World War II. Some of the button factory shell heaps still remain.

Right image source: The Freshwater and Marine Image Bank at the University of Washington

(Entry by Dr. James Theler)