3 Tricks to Catch More Trout on Mouse Flies

Mousing at night for very large trout can become an angling addiction. Photo: Chris Gerono

When I first heard that big trout would come to the surface to explode on mouse flies, I plunged headfirst into madness. After work, I would rush to the river, tie on a mouse pattern at sunset and then fish through the night. I’d smack, strip, and skate my mouse patterns for hours in the moonlight with no success. Then a few hours before dawn, I’d reel up and return to my car to try and get a few hours sleep before going back to work, determined to have better luck the following evening.

For three nights, I kept up this grueling schedule until finally, on the fourth night, I saw what looked like a toilet flushing around my mouse fly. I set the hook and immediately felt a heavy, struggling weight on the end of my rod. After a short battle, I landed a hefty, 22-inch brown trout, my mouse dangling from its kyped jaws. That fish started it all, and I’ve been completely obsessed with mousing ever since.

I’ve fished mouse flies nearly everywhere I’ve been—from New England and New York to Montana and Patagonia. I’ve caught trout on mice in many different rivers, and even in some lakes, hooking up with the big fish at different times of the day and night, under all sorts of conditions. During my years of rodent fixation, I have discovered ways to make mouse flies work for me nearly every time I hit the water. And, while there are many little intricacies to successful mousing, three details in particular will help you connect with more mouse-eating trout.

Small mouse patterns or those with a slim profile work better than fatter, more realistic imitations. Photo: Kubie Brown

1. Fish a Skinny Minnie

Almost every angler who takes up mousing has a “big fish eat big flies” mentality. They head to their local fly shop and buy the biggest, most realistic mouse pattern they can find. Then they tie this New York City sewer rat to their line and splash it down like an atom bomb for a few hours and wonder why they aren’t catching anything. While I don’t begrudge this sort of ambition—as I used to fish that way myself—if you want to catch big trout on mice and catch them consistently, use smaller, thinner flies.

While there are places in the world—such as New Zealand, Patagonia, and Alaska—where trout key in on mice or lemmings, in most places trout aren’t actually out there hunting rodents. In fact, when trout hit a mouse fly on the surface, they likely don’t know what they’re eating. Instead, they’re simply responding to the commotion of something splashing around, and that’s where thinner profile mouse patterns come into play.

After months of eating struggling stoneflies, caddflies, hoppers, and such off the water’s surface, trout begin to associate anything that’s making a commotion on top of the water with food. When you go mousing, you’re capitalizing on this behavior. By using a smaller mouse pattern you’re giving trout something that looks edible and will trigger their predatory instincts. This is especially true for the larger trout you’re after, which are more opportunistic and less hatch oriented, meaning that you can still catch some hefty fish on relatively small mouse patterns.

My favorite, most productive mouse patterns have a thin profile and give off the impression of prey. These flies include the Morrish Mouse, No-Miss Mouse, Mr. Hankey, and Master Splinter. Like a Great White mistaking a surfer for a seal, trout strike these mouse patterns because they look and move like something the fish are used to eating, rather than looking like an actual mouse itself.

The mouse pattern’s commotion on the surface is what triggers strikes. Photo: Chris Gerono

2. Strip or Skate?

There are only two real ways to fish a mouse pattern—stripping and skating. Both techniques can be incredibly effective at producing both hard strikes and subtle inhales from hungry trout, yet it’s rare for both methods to be effective in the same area at the same time. Each technique works best in specific water conditions, and knowing when to strip and when to skate a mouse will help you get more trout to respond.

Stripping is a more aggressive technique. Cast the mouse slightly upstream, and then start stripping, ripping, and popping it across the surface. It’s a great choice for faster, choppier water where the trout don’t have a lot of time to look the fly over and are more inclined to dash out and smash prey. This is especially true in areas with a lot of structure, such as log jams, or along sharp drop-offs where big trout will hold against the bank and wait to pounce on meals passing by in the fast current. Stripping can also be effective in still water or on very slow-moving currents, as long as you mix in plenty of twitches, pauses, and stalls into your stripping rhythm to give the trout time to strike.

Skating a mouse is best done on long, slow flowing runs where the current is moving at roughly a walking speed. These areas allow the fly to create an impressionable V-shaped wake as it moves across the surface, ringing the dinner bell for hungry trout, especially in shallower water. Cast down and across the river at a 45-degree angle and then swing the mouse like a streamer. You can also add a bit more action to the presentation by raising your rod high and wiggling the rod tip, causing the mouse to flutter and dart as it moves. This added movement is especially effective when skating mice through the tailouts of pools above fast water or across the top of mid-river boulders and other underwater structures.

Overcast, cool days can provide opportunities for daylight mousing. Photo: Chris Gerono

3. The Right Light

Because most mousing is done at night, many anglers don’t consider light when they plan a mouse-fishing expedition. However, the amount of available light can affect the trout in different ways, and understanding the best light conditions for mousing can make all the difference between getting consistent strikes and going home empty handed.

The most obvious light source when mousing at night is, of course, the moon. When it’s full, that giant reflective orb in the sky can provide enough light to make you feel like you’re fishing in daylight. Yet at the same time, a full moon might be one of the worst times to go mousing.

While this isn’t universally agreed upon, I’ve found the mouse bite to be slow or even completely non-existent during a full moon—as have most other anglers that I know. Perhaps the trout feel more vulnerable to predation under the full moon’s light or they can simply see more food in the water and are less apt to want to choke down something as big as a mouse.

Whatever the reason, a full moon is rarely—if ever—a great time to mouse, as is the new moon. When there is absolutely no light on the water, trout seem to become completely inactive. However, clear nights during a half-moon or quarter-moon phase put a gentle, flickering glow out onto the river, and these are my most productive mousing evenings, as the trout seem to have just enough light to see a stripped or skating fly without feeling exposed.

Other ideal times to mouse are the first half-hour after sunset or the first half-hour before sunrise. In this half light, trout become aggressive and will occasionally smash a mouse fly as soon as it hits the water. Pay particular attention to any shallow, backwater areas with slow or completely still currents, as these are often the first spots trout will move into when they’re beginning or ending their nocturnal feeding sessions.

Believe it or not, you can have good luck fishing mice during the middle of the day, especially when it’s extremely cloudy and windy on the water. Under these conditions, your mouse makes a big impression on the surface, and it may attract trout that may be having trouble finding and targeting insects in the low light and turbulent water. If it’s raining or even snowing, as well, even better. Accordingly, it’s a good idea to keep a mouse fly close at hand any time you’re planning on fishing during stormy weather, as it will often induce strikes when nothing else will.

The author shows off a fat rainbow, as well as the crazed look of a mousing fanatic. Photo: Kubie Brown

Of Mice and Fishermen

Be warned: mousing can become a complete obsession. It’s a way of fishing that appeals to thrill-seeking anglers who are tired of the typical casting-and-drifting style of fly fishing and want to make something happen. The desire to see a beast of a trout explode on the surface becomes a driving force that can and will send you out onto the water every night, creating a level of sleep deprivation that tickles the edges of insanity.

Yet, it’s in that crazy state of mind where you find the true beauty of mousing. You come to love it and see it as a technique that allows you to interact with trout on an entirely raw and predatory level which dry flies, nymphs, and even streamers simply can’t provide. And as long as you keep the right tricks in mind, it’s an interaction you can experience almost every time you pick up a mouse fly and head off into the madness of the night.