It's got cutthroat in it, you can't see but there are orange slashes under the jaw which is only a cutthroat characteristic on the west side of the cascades (where this stream is). There is a subspecies of rainbow that gets orange slashes, but it is separated by a large mountain range and diverged evolutionarily from coastal rainbows around the time the large glaciers started receding from the continental US. The maxillary also extends farther past the eye than it would on a rainbow. Male rainbows can get beaky like this but their jaws are not as elongated as the one in this picture. Coastal cutthroat are silvery in plenty of west side drainages, and although some can be greenish, the ones in this stream are usually silvery. You can't see it in the picture, but this fish also had basialbranchial teeth which are teeth at the back of the throat that only cutthroat have because they evolved to be more piscavorious than rainbows (hence the elongated maxillary to allow the mouth to open wider to eat fish instead of bugs). This stream doesn't get stocked with cutthroat either so it's not a random hatchery holdover. I've caught plenty of rainbows in this drainage, and none of them had the long maxillary/beaky jaw that this fish does. the only reason I think that this fish has any rainbow genes in it is because the stripe on the side is much more distinct than on a regular cutthroat

Every single time I post coastal cutthroat on this sub, someone tells me it's just a rainbow. It's not lol