Re: Tips for Rocky Mountain N.P.
RMNP is my home range and I know the Moraine Park trailheads and trails like the back of my hand, although I have only fished the Big Thompson in MP a handful of times. My targets are usually the high country lakes way above MP. The BT in Moraine Park is a delight to fish. It is scenic and the stream meanders through a rather flat meadow with thickets of willows here and there. I have only caught rather small browns on caddis and midge dries. A huge elk herd winters here every year and I always wonder what their impact is on the BT in the open meadows of Moraine Park.
You most likely will have this stretch of the stream to yourself. You will see tons of hikers, but few anglers. The stream closest to the campground is almost void of any brush at all, so leave the waders behind if you want. There are very few people even on this stretch. The hikers tend to stay up on the trails of the Cub and Fern Lake trailheads. If elk are around (probably not during the summer) then there will be tons of idiots in their cars stopping and holding up traffic on the road.
The stretches of river up towards the Cub Lake trailhead has better fishing IMO but is loaded with willow thickets. Although I have never fished the stretch of the BT past the Fern Lake trailhead, it seems as if there are tons of little brookies and browns in every hole. You can even spot fish as you hike past the dozens of holes along the trail. This stretch is loaded with timber and willow thickets but you could get in there easily with waders. And you can drive right up to the trailhead and the first mile or so is very flat.
Man, if you're going to come all the way to RMNP just to fish for trout, why not make the effort to get to some Greenbacks? I personally would recommend some lakes above Moraine Park. If you have the time and ability to make the 10 mile round trip hike, Fern, Odessa, Spruce and Loomis Lakes are some of the park's best Greenback Cutthroat lakes. Loomis especially holds a few high country brutes. The inlets and outlets at these lakes are pure Greenback heaven. And if you think the scenery in Moraine Park is fantastic, the scenery above these lakes will mesmerize you.
For mileages (estimates only here) - From the campground down to the flat stretch of the BT in Moraine Park is about a half mile. The Cub Lake trailhead is about another half mile past that and the Fern Lake trailhead is about two miles from the campground.