In watersheds with salmon, like many rivers across Alaska and the Kamchatka Peninsula, rainbow trout thrive on high protein diets provided by the salmon life-cycle. After wild salmon return to their natal rivers and spawn, they die. When the salmon carcusses’ decay, trout eat chunks of salmon flesh tumbling down the river. Understanding this concept helped anglers begin flesh flies fly fishing fly fishing with flesh flies, which has arguably become one of the most efficient tactics to catch trophy rainbow trout.
Other productive ways to catch these protein-packed trout is by fishing the salmon fry bust or fly fishing with beads. Just remember, these salmon based watersheds have short seasons, so make sure you know what protein source the trout will be keyed in on when you show up to fish!
Flesh Flies for Trout
Flesh flies imitate salmon flesh so chances are you will only ever use these flies in Alaska. While most flesh flies for trout are extremely simple patterns to tie, there are some considerations for selecting the best pattern to fish. These variables make the difference between a slow day of fishing and a memorable one. Fly color, fly size, fly weight, fly texture, and even fly smell are key considerations.
Fly color:
When you buy a fresh wild salmon filet at the store it should be bright orange. If you took that filet and left it in a bucket of water you’d notice it slowly turn from that bright orange into peach/cream into an off-white and then eventually into a dirty-sock color before it degrades beyond recognition.
Understanding of this color change should be considered in correlation to time of season when you are fishing. By this we mean that in the early season the first salmon flesh in the river will likely be gut bucket remnants from filet tables, so peachy colored flesh is a good choice. Once the post-spawn salmon start dying, try fishing with off-white colored flies. Late autumn (and even early spring) is best for dirty-sock.
Fly size:
Like fly color, fly size can be an important factor for choosing your flesh fly. As a generalization, the process of decay breaks things down from large to small. In theory, this correlates to ‘fresher’ flesh being larger chunks and older flesh becoming smaller chunks – correlate this to your flesh fly color if you can!
However, we know big fish move farther from their lie for bigger meals – so sometimes fishing a “mega” flesh fly results in connecting with trophy fish. While it is illegal to fish within 200 yards of a filet table in Alaska, you can learn a lot about the massive sizes of flesh a rainbow trout will attempt to eat. We’ve frequently watched rainbows eat whole salmon rib cages, skein and roe sacks.
To the contrary of the argument for “mega” flesh flies, sometimes a “micro” flesh fly presents just innocently enough to fool the massive rainbow you might be sight fishing too. The main thing here is to change up the fly size until you know what they want!
Fly weight:
Salmon flesh tumbles along near the bottom of rivers at the whim of the current. While it is important to get your fly down in the water column, it is also important that your fly is not overly weighted. Too much weight hampers its natural appearance of drifting around in the hydrologics. In our experience, it is okay to add some weight to the fly itself when tying, but we prefer to control the depth with split shots when on the water.
Fly texture:
A decaying salmon obviously has different textures of tissues, bones and scales that all decay when they die. This means you can get creative when tying flesh flies! While its hard to argue the efficacy of rabbit strips for cranking out lots of flies, other materials have their value.
Egg yarn in natural colors is very popular as well. Not only is it easy to tie with, but it has another secret advantage; the material gets caught in the small teeth that trout have making it harder for them to quickly spit out. Why’s that important? We know guides that swear they have observed trout eating a flesh fly and spitting it out before the angler’s strike indicator ever moved. This surely is uncommon, but if egg yarn gives the angler a split second more to set the hook it might be worthwhile!
Fly smell:
The difference between fly fishing and bait fishing is, well, smell. Fly fisherman do not use artificial scents on their flies and in many rivers it is illegal to do so. While purposefully enhancing your flies with scent is a big ethical no-no, it’s equally important to realize you might be accidentally diminishing your fly’s efficiency by adding unnatural smells to your flies. The two most common ways this happens is by the use of fly tying glues/cements (many guides purposely do not use glue when tying flesh flies) or from cigarette smoke becoming infused with the fly.
While this seems like a somewhat silly consideration, wary Alaskan rainbows have been witnessed by guides floating downstream behind flesh flies before deciding to eat or refuse the imitation – and we believe they are oftentimes smelling the fly more than they are looking at it!
Alaska Flesh Fly Patterns
There is a tremendous difference between the rainbow trout you catch in Alaska and those that you catch in the lower 48. That difference? Trout rivers in Alaska are packed with salmon-fueled protein while most trout fisheries mainly provide diets of aquatic insects.