The Zug bug was originally designed in the 1930's by J.Cliff Zug in West Lawn, Pennsylvania, USA and it became a popular fly within the Catskills Mountain region.
The Zug Bug Nymph fly pattern is thought to be a variation of a nymph called the kemp bug. In the 1940's its popularity spread to the mountainous regions of Western America. It was used successfully in Yellowstone National Park and the Sierra Nevada. It is one of those must have flies. It rates along with Pheasant Tail nymphs, Gold Ribbed Hare's Ear nymphs and Prince's nymph as one of the top 10 nymphs that you must have in your fly box. It is the use of the green Peacock Herl and Peacock Sword for the tail gives this fly it's efflorescent qualities that makes it so alluring and successful. It can also be used as a stonefly imitation. Cliff Zug developed the zug bug to imitate cased caddis and caddis larvae. The design demands that the wingcase is only tied down at the front near the eye of the hook. This gives the zug bug a juvenile caddis-type wing appearance. I have had success with using a zugbug as part of a dropper rig. In slow moving streams it works great near the bottom fished dead a drift on the current.
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