December-February– I have had excellent fishing days and others when I couldn’t even catch a whitefish. I have noticed fishing improves after two-three days of air temperatures in the 40s. This year Boise had a warm spell in late December. A friend and I hit the river just a few days before Christmas. We were able to land twenty fish using nymphs.

Another warm streak occurred towards the end of January. This time I tried my luck with streamers. Again I was able to catch some fish.

However, I tried a couple of other times during colder temperatures and the fishing was slow. You can still land fish on colder days, but don’t expect it to be spectacular.

Tips for winter:

• Fish slower runs. Walking pace-half the speed of a walking pace. Try large back eddies and deep holes as well. Rainbows will sometimes hold in slightly faster runs, but the browns will most likely be in the slower ones.
• When fishing streamers try swinging the fly with occasional slow strips. Also, a sinking line will get the streamer down in the deeper holes and runs.
• Pick up rocks and check out the bugs. The nymphs tend to be smaller this time of year.
• When nymphing make sure you are fishing close to the bottom. If you are not ticking the bottom every three-four casts raise your indicator or add some split shot.
• If you chose to fish somewhere between Linder and Middleton bridge know that you will often run into waterfowl hunters. They tend to be out early in the morning and a couple hours before sunset. Just be respectful and move past their blinds quickly. This should be obvious, but please give them space and don’t fish near their decoys. If you see them in the parking lot they might give you some good fly tying feathers if you ask nicely. 🙂
• Fish during the warmer part of the day. 1:00-4:00 p.m. is usually good.

Winter Fly Patterns:

Small nymphs will probably be your best bet. Zebra midges (I like olive or black), pheasant tails, and red copper johns in sizes 16-20. Sometimes small caddis patterns do the trick as well. I have also seen mop flies hook a fish now and then.

If fish are rising it is most likely to midges or blue wing olives. However, dry fly action this time of year is less common.

I find smaller streamers are often needed in the chilly weather. Traditional wooly buggers seem to do the trick. Small sculpin patterns with weighted heads can also be effective. Don’t be afraid to experiment with different streamers.

Hope that helps