A Mechanized Panel Grading System for the Golden Shiner: Proof of Concept

In 2008, we conducted one swimming performance and metabolism study and one transportation study on the golden shiner, Notemigonus crysoleucas. During field work for these experiments, we consulted baitfish farmers, observed harvests, and participated as workers in actual in-vat grading events. We concluded that the physically demanding in-vat grading process could be improved by mechanization, so we developed a prototype system based on existing grading panels. We constructed a gantry system to raise, lower, and pull grading panels through the length of a rectangular holding vat. Electrical power for the prototype was provided by a 12-volt marine battery. We conducted three successful fish grading events. The grading panel remained in contact with the vat floor and vat walls at all times. No fish evaded the panel by swimming under or around the panel, and all unwanted animals such as crawfish and tadpoles were captured. After one of the tests, the farm manager reviewed the graded fish, approved the grade, and immediately loaded the fish for shipment to a customer. A limited benefit-cost analysis indicated that the benefit of mechanization during the first year of operation was approximately US$8,600. The golden shiner Notemigonus crysoleucas is cultured for use as live bait by anglers. Golden shiners are harvested from ponds containing a mixed-size population, and are placed in rectangular holding vats, where they are sorted into specified weight categories. Workers on Arkansas baitfish farms typically sort golden shiners by physically pulling rectangular panels comprised of a set of uniformly spaced vertical rods through a vat holding as much as 400 pounds of fish. We developed and tested a device that replaces physical effort with machine power to accomplish the grading process.