"ine, gill net, channel net, bull rake, seed fork, grabs, escalator, or dredge; and (b) any net, seine, trap, pot, tongs, rake, fork, trotline, or other device or appliance when used for taking or attempting to take fish for a commercial purpose. (12) Commercial purpose means: (a) being engaged in buying or selling fish; (b) taking or attempting to take fish in order to derive income or other con" . . . . . . .