As fly anglers, we are all cultured to believe that trout eat insects and nothing more. Trout gently sipping bugs from the surface of a calmly flowing stream paints the image of fly fishing narrative. It’s what we all learn in the beginning. Anything else would be culturally unacceptable in the fly fishing world. For years, I believed that no self-respecting trout would ever eat anything other than some form of aquatic insect or terrestrial bug. Fly fishing in Appalachia ingrained that into my head. That was right up until I read an article in Fish Alaska magazine about rainbow trout eating mice.
The level of disbelief wielding in my brain about what I was akin to what my grandfather thought about space travel. It wasn't happening. It didn’t happen and it wasn’t ever going to happen. Sure, I had seen a brown trout slashing at other fish and had buddies in the upper midwest that talked about mouse fishing for brown trout at night. But never, ever would a rainbow trout chase down and annihilate a mouse. Rainbows weren't that type of aggressor and besides, they didn’t get big enough to eat a mouse. Right? That’s what I, the 25 year old knower of all things trout, thought. No way.
I must have read that story 10 times before I finally accepted that the writer must have had a very minute amount of success using this “mousing” method for Alaskan Rainbow Trout. Back in those pre-internet days all we had to rely on was a trusted publication with mass circulation and a photo album. Yes kids, before internet and social media we all carried photo albums with us to trade shows, speaking engagements, etc. A three ring binder notebook full of print photographs. Sometimes carrying just one album was not enough; depending on the situation and competition. It was the only way to advertise your trade of skills and to prove that you weren't just a liar. In fact, the next trade show I worked at was where I found living proof that the “mousing” I had read about was in fact real. Not only real but a viable method for targeting the largest of the species. I was befuddled.
At that show, I met a lodge owner that hosted the writer for the story I had read in Fish Alaska. He explained to me how the whole Alaska trout universe operated. Upon understanding, the program made sense. It was no great consequence that this guy gave me my first job in Bristol Bay some years later. I adapted his explanation into my own version. If you have fished with me as a lodge guest, client or friend new to the Alaska trout universe, you have heard me deliver this lecture. Some of you may have heard it more than once. Its as follows - Alaska rainbow trout live a different life and lifestyle than lower 48 rainbow trout. They only have a three, maybe four, month window of time to get in a full twelve month life cycle, as compared to a regular lower 48 rainbow that might have nine or ten months to get everything in before the water cools to a point that their metabolism slows to a crawl. So, in three months, an Alaska rainbow trout has to find a girlfriend, find a house or two and, it has to eat everything it can. And by eating everything it can, I mean everything starting with the highest forms of protein first. In spring, voles (mice) and leeches are the prominent source. As summer comes so do the salmon producing first eggs, then flesh after the spawn is over. Fall brings on the sculpin, more leeches and whatever else they can find. All that along with finding a girlfriend and a couple houses in three months. Its a lot of living.
But more importantly, the “mousing.” While in spring and summer hordes of mice or voles, red back voles to be specific, make their seemingly ridiculous trek transitioning from tundra animal to aspiring olympic swimmer. Why? I don’t know. Some say its because of some migration pattern. Maybe. Others say its because they are seeking the same things all mammals seek. Could be. Why a tiny little vole would jump into a raging river flowing at upwards of ten knots is beyond my level of good reasoning and understanding. Why do voles jump in the river? My opinion is because they just do and I don’t care why as long as trout continue to eat them. If you are more worried about why they do as opposed to the consequences of it, you should probably change the channel. I heard re-runs of the greatest Bob Hope Christmas specials were going to air in July. You might check that out.
The first time I watched a rainbow “mousing” left a scorching imprint of what really happens in the bush. Eat or get eaten. Brutality in its purest form. This poor little red back vole was just swimming across the river in a narrow channel that didn’t seem deep enough to hold a rainbow. Its swimming along just trying to get to the other side for who knows why and this two foot rainbow manifests, chases the vole, swirls and smashes on it but misses. Then it swirls and smashes again only to miss the vole again. Just when we all thought the show was over the trout comes back for one last grab. Third times a charm right. Nope. Another swing and miss precluded with a full body leap out of the water to come crashing down on top of the vole, missing completely. All the while this vole is still just swimming. Doing its thing. While I am sure the thing was horrified beyond belief, it didn’t change its pace or course. Probably because it wasn't capable of physically fighting the river current. The fourth and final attempt from the rainbow proved worthy but not without show. The fish came back waking the even more shallow water like a great white shark chasing a seal. It literally powered its way through six inches of water to annihilate the vole just before it reached the other side of the narrow river channel. Pure unforgiving brutality. I and my Swiss clients stood there looking at each other. Until that moment, we had all struggled with a language barrier. they didn't speak much English and I didn’t speak Romansch. Once that rainbow crushed the vole, we all understood what needed to happen and it did.
The first pass with a “mouse” pattern fly was nothing less than epic. Three chases and then a hook up. Next guy cast and had four chases and then hooked up. This went on all day and the rest of the week. At one point, I even took all the flies out of my pack except mice. The fact that they witnessed the initial sacrificial lamb significantly flattened the curve. They knew not to set the hook until they felt weight on the hook. Like the precision watches the guys built, with systematical precision they took apart the entire river and covered every bit of water with mouse patterns. All week.
Now I have clients that book for Alaska specifically when “mousing” is peak. Usually, June and July. They bring only mouse pattern flies, and floating seven weight lines on 9’ rods. Most folks bring two rods, just in case the unspeakable happens. The bush isn’t a place to not be prepared but, that’s another story.......