I intend to go in early June in Bosnia for fly fishing grayling and trout in these rivers:Pliva,Ribnik and Una.Someone can tell me some models and sizes of dry flies and nymphs are indicated on the rivers ?Thanks

There are heavy hatches of upwings on the Ribnik in particular. Fish respond well to these and there can be spectacular rises of fish. As a result dry fly is the best method. Between hatches fish can be rather dour. With the heavy hatches fish can be very selective and some kind of crippled dun is the best approach. The fly species are the same, or similar, to here so that similar patterns can be used. The same is true of nymphs with dull pale beadheads working well. As usual it is more about presentation and technique than the fly pattern.

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