Peacock This well known pattern is a version of the original pheasant nymph used in the mid eighteen hundreds on English chalk streams.
Many people use it in both lakes and streams.
I consider it the number one lake nymph when imitating the Callibaetis nymph. In rivers I still feel the Birds Nest is a more successful pattern. Fish this fly under a long light tippet and slowly swim it around or above weedbeds where Callibaetis and Siphlonurus nymphs abound.