Re: BWO emergers not working during the hatch
sounds like time for a dropper or a smaller or larger fly combo, maybe even a twitch. Try positioning yourself so the nymph reaches the end of it's drift & starts to swing up in the vacinity of the feeding fish. Often during a hatch just dead drifting a fly just doesn't work so change your tactics & fly size or color. A hatch doesn't start instantly. There will be a lot of nymph activity before it starts. Look for the type of bottom & river flow that insect likes & fish downstream from there judging where the bugs will be in the water collumm where the fish are feeding.