TroutBum- Ill be heading out there in a few weeks for the entire summer/fall. Ill be working at a ranch as a guide so feel free to message me if you have any questions.
In early june, you will still be experiencing effects of the runoff. It ran a little late this year. Conditions will be quite similar to last year. Rock creek will be in top notch shape. The salmon fly hatch is very intense on rock creek. It starts in mid-late may and lasts through mid june, but I still do well with that pattern till the end of june. During this time, you might experience some pressure, but nothing like high pressure on the east coast. Finding a camping site is quite easy in the area. I would suggest a hike/fish day if you are fishing rock creek in june so you can get away from the crowds. The upper part of rock creek is better at this time of year since it runs much clearer, and you will have much better chances of dry fly fishing. If you are fishing nymphs, I would cast out a LARGE #2-10 stonefly pattern and drift it to the bank. This works extremely well.
You might also run into the golden stone hatch which is great as well. #2-6 on the nymphs and a little smaller on the dries. Dry fly fishing will be better here since they hatch toward the end of june.
The Bitterfoot is great in mid june. This is when it generally gets clear. Elk hair caddis #14-18, adams, and PMD in the same sizes work great for dry fly fishing. Also, you might catch the beginning of the green and brown drake hatches, which I think are the most prolific on the bitterfoot. Around Missoula wading will be difficult since it grows in size, but if you fish downstream or up you should be fine.
Big hole- Start out by saying that the big hole provides breathtaking scenery. Great montana river as well. I dont have much on the fly selection here, but stop in at a local fly shop they will hook you up. The lower sections get a bit fast and unwadable during the run off. One piece of advice...mosquitoes are crazy on this river especially in the valley. Beware, because I have left my spray at home before, and it was horrific. During late june, they peak, and be alert.
Gallatin river- By far my favorite river in Montana. I will be guiding right in this area, and I just love it. Make sure you hit up the stretches in Big sky, and gallatin gateway just south of Bozeman. The views are breathtaking, and the fishing is quite easy. Not too many large trout, but occasionally you will pick out some large browns. This stream tends to stay cold year round, since it is fed by mountain streams. My favorite part about this stream is that you dont have to deal with the damn floaters all day, but you might experience some rafters especially in the canyon in gallatin gateway. Access is awesome since it runs right along rt 191 basically the whole length. Fly selection for the time you are there would be all standard dries from caddis, salmon flies, PMD, and in the morning the spruce moth hatches are AWESOME. all sizes around #12-18. Very wadable river, and I strongly recommend you do not pass this up. Camping in the area is quite easy to find.
I might stay away from the madison since it is vulnerable to run off issues. The west fork brings in ALOT of mud during run off, but you might miss the mud, so hit it up if you can. I would float this river if you are going to fish it. I have not fished the lower madison, but I hear that it does not mud up as well as the upper. The upper madison is amazing fishing if you can miss the mud. Known as the 60 mile riffle.
Bighorn- A few of my buddies are saying that the bighorn is fishing better than any river in montana right now. If you are looking to pull out HUGE fish, the bighorn provides just that. Although the pressure on the bighorn is quite heavy, you can find spots especially near the confluence with the yellowstone, where it slows down a bit. The upper part is very packed with floaters and is very annoying, but like I said. The bighorn is a great river to fish while you are out there. In the summer, it gets extremely slippery. I do not really know why, but moss tends to grow here more than any river in the states if you ask me. Parachute adams and BWO in smaller sizes work great in june here. You might also be there to see the little yellow stonefly hatch, which is my favorite on the bighorn.
As I said before, camping in all these areas are very easily accessed. Beware of bears, and bring bearspray or even a sidearm if you are paranoid about them. If you get a chance to fish the park, I would do that. There are a lot of really nice streams and spring creeks. Ill be located just north of yellowstone in emigrant near the yellowstone river. Hope your trip goes well, and if this is your first trip, I will tell you now...it will NOT be your last. Once you get out there you will want to go back as much as possible. Hopefully this info will help, and I am not a total expert out there, so make sure you stop in at a fly shop for the daily menu.
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