1. Be mindful of hook size. Some mouse patterns employ very large size 2 and 4 gap hooks with Northern Pike or larger game fish in mind. With a hook that size, it can be fatal for trout. A smaller hook accommodates a smaller mouse pattern. Which is an appropriate imitation for the actual size rodents that trout eat. In many cases, Alaskan rainbow trout are actually eating voles rather than mice. So, for even the largest trout, a size 6 or 8 hook is ideal. Always pinch your barbs.
2. No light tippet. When we’re mousing for trout, we’re often fishing structure – logjams, root balls, down trees, etc. You can take one guess on where a rainbow will run when hooked in front of a logjam. Sometimes, you have to put a lot of pressure on the fish to keep it from running back into structure. Additionally, these Alaska rainbows are not leader shy with this technique. There’s no reason to use a 9ft 3x manufactured leader for mousing. 5-6 feet of 20lb test works great.
3. Disturb the surface. When mousing for trout the most important attraction feature is the surface disturbance. Plop, wake, and wiggle. Rainbow trout that regularly eat mice are keyed in on the sound and sight of these furry critters falling into the water and swimming across the surface. Big Alaska rainbows will often times smash a mouse as soon as it hits the water. The aesthetics, color and life-like look of a mouse pattern are far less important than the action on the surface of the water. Find a fly that casts well and skates right side up consistently.
4. Target fish in shallow water. This is a pretty easy concept for even a novice angler. Fish that are closer to the surface are much more likely to eat a surface fly. Yes, at times our rainbow trout come out of the deepest darkest holes to crush a mouse pattern. With that, a trout feeding in one foot of water is likely to be a mouse eater. On the flip side, a rainbow that is 8 feet down under a logjam enjoying a salmon flesh buffet may not have an interest in expending the energy to eat a surface fly. Not to mention, sight fishing to shallow water mouse eaters is one of the most exciting things in the sport.
5. Set the hook (the right way). This is a tough one. Let’s start at the beginning. Rainbow trout will eat a mouse in many different ways. Sometimes they explode on the pattern creating a big splash and/or boil. This is, of course, an exciting part of mousing for trout. In other cases, they will sip a mouse very slowly like it’s a green drake on a spring creek. With an explosive eat, it is common for anglers to have an immediate jerk reaction and set the hook to early, ultimately pulling the fly out of the fish’s mouth. When a trout eats slowly, the anticipation is the folly. And again, anglers set the hook too early. The common adage in fly fishing is to say “God Save the Queen” between the eat and the hook set. This allows ample time for the fish to take the fly fully. Another common mistake among anglers is that they have no room to trout set because they are high sticking to get good wake and wiggle action on the fly. In this case, it can be useful to side set or even strip set in order to properly hook the mouse eating trout. And lastly, whenever possible set the hook downstream. With any technique, it is very difficult to hook our Alaska rainbows by hook setting directly up stream and away from the fish.
6. Don’t give up. Missed a fish because of a bad angle or early hook set? Cast that fly right back in there. Or even better, wait 5 minutes, adjust your angle, then try again. Our rainbow trout in Bristol Bay are voracious, meat eating opportunists. Depending on the river, these fish can get pricked 2 or 3 times and still want to eat.