For those looking for info on what is happening at Rock Creek, John Perry has info for you here:
Here is an accurate fishing report: Rock Creek seems to be the only major creek or river in Western Monta
na that has any sort of fishing. The salmon flies are out on the lower section-but no fish are tuned into them yet. The water level has been fluctuating a bit and with these very high temps. we could see it become unfishable for awhile. If the creek does not blow out soon-you could have some good fishing with an indicator system with two flies. Wire worms, san juan worms, and glints seem to be doing the best. Some action on the girdle bugs and jumping jack flash. Dry dropper may be a good choice.
Try using a large salmon fly pattern dropped off with a pink san juan worm or a nymph that represents the salmon fly nymph. Look for drop offs, slower water and meandering foam lines-adjust depth accordingly. You could have a little bit of fun.
The Missouri river has been fair to good fishing also. No consistent dry fly action. Once again a double nymph rig is by far your best chance! Try using a large wire worm dropped off with a glint, carpet or sow bug, small crawdad pattern, or a smaller san juan worm. Adjust your leader depth from 6 to 10 feet-depending on water depth and current. Also, you may want to add B or BB’s to get down to where the fish are-once again depending on water depth and current.
I only have a couple of reports on Georgetown Lake-but they were pretty good. If fly fishing, try using a subtle little indicator with a small nymph-not too far down from indicator. The colors that seem to be working are gray, bright red, and black. I’ve also heard that back swimmers have been working with a very very slow stop and go retrieve. Sizes vary from 12 to 16.
The attached picture is of some salmon flies on lower Rock Creek on Memorial Day.