This pattern goes by several different names—Del’s Merkin Crab or Del Brown’s Permit Fly, to name a few. Semantic differences aside, three things are certain—it was invented by Del Brown, it resembles a merkin crab, and it is one of the best permit flies ever invented. But why is it so popular? The primary explanation would be the number of permit taken on this fly, which is relatively astronomical. But when you take a closer look you’ll see another reason—it’s paradoxical simplicity. I say paradoxical because this fly doesn’t look simple at all in its finished form. And yet it consists of relatively few ingredients: two feathers that mimic pincers, a yarn body, Sili Legs and dumbbell eyes. Nothing more, nothing less.
After decades of permutations there have arisen different shapes-styles and variations of Del’s Merkin Crab. Whatever the style, it’s worth sticking to several basic rules at the vise. First of all, always add your weight near the hook eye—this is the secret of proper fly position after it drops into the water (pincers up and out, like a real crab defending itself). Second, experiment with body materials. Originally the fly was tied with rug yarn (Aunt Lydia’s Rug Yarn, which has since been discontinued), but you can substitute EP Fibers or a Mono Yarn for extra stiffness (as we did with our variant). Lastly, the final trim of the body should be dictated by your ultimate presentation goals: a narrow body for a faster drop in deeper water, or wider body for a slower drop in shallow water.
Last but not least, try to match yarn colors with the colors of the crab in your fishery. If you’re heading to new water and are unsure, yarns in cream or tan are a safe bet for filling your fly box.