I have only fished for them in Alaskan rivers that had an active salmon run at the time. Egg patterns were the fly of choice at that time.

They have a reputation of not being very selective. If you have a decent assortment of standard patterns, such as hare's ears, prince nymphs, pheasant tails in size 10-14, some wooly buggers and some Adam's dries, I am sure you will catch plenty.

Ted