Ruddy
Ruddy Fly, Berners

FLY FISHING DICTIONARY
Midge
Midge Flies
   
dun   English
  A growth stage of the mayfly with the Latin name subimago (= sub adult) that encompasses the stage just before adulthood. As a nymph transforms itself and its wings grow at the water surface or at the shore, it becomes a dun. The molting, namely the backing out of its old shell, is usually performed in a few seconds. After becoming a dun, when the last molting is performed, it becomes a spinner (= imago, adult). Although the period of the dun stage varies according to mayfly species, it is 24 to 48 hours long on average.
  Although the dun resembles the spinner in general, the body of the dun is thicker, and the tail is shorter than that of the spinner. The body color is modest, and it is without luster on the body surface. The wings are gray (dun color) or straw color. In the spinner, the body is slim, its color is clear and glossy, the wing is transparent, and the tail is long.
  When a hatch takes place and the hatching process is completed successfully, most of the dun on the water surface will fly away immediately. The time on the water surface is short. Therefore, it is generally assumed that few chances exist for the dun to be preyed on by trout. Most likely to be preyed on by trout during hatch are the emergers - the ones that failed to become duns in the hatching process (stillborn), and the duns unable to fly away from the water surface (drowned dun). They are especially easy to be preyed on by trout, and many fly patterns imitating the dun are devised.
ReferenceHatches II, 1986.
spinner, hatch, hatch pattern, emerger, stillborn, drowned dun
 
 
 
 
Selected
Selected Headings


Top
Top
Stomach content of Yamame in May. Tanzawa Mountains, Kanagawa Pref., Japan.
Stomach content of Yamame in May. Tanzawa Mountains, Kanagawa Pref., Japan.
Next
Next