.......................  ......Fly Fishing Yellowstone National Park

Fishing Cold Water - Part Seven - Midges
So far, I have only discussed fishing cold water when there aren't any hatches
occurring. Everything has been to do with getting a nymph or larvae imitation in
water that's moving slowly. This is necessary due to the fact trout aren't going to
expend much energy in fast water that's very cold. They much get out of the fast
current in order to survive. If they didn't, in most cases, they would expend more
energy than they could replenish with food. However, hatches can and do take
place in cold water.

Midges can and do hatch in water that's in the mid to high thirties in terms of
degrees Fahrenheit.. Winter stoneflies (of two different families) can and do
hatch in water in the low forties. Some of these are wingless. They look a lot like
ants. If there's snow on the banks and rocks in the stream, you can usually see
the dark adult stoneflies crawling around. Like all stoneflies, these crawl out of
the water to hatch. When they do crawl out of their normal hiding place and
migrate to the banks to hatch, the trout know it and take advantage of it.

The third type of insects to hatch in cold water are some species of Blue-winged
olives. They can and do hatch when the water is between forty-five and fifty

I will write about fishing each of these hatches in this series starting with midges.
I think most anglers ignore midges in the freestone streams. They are even
ignored in some spring creeks which almost always have huge hatches of
midges. Some anglers do have very good success fishing tailwaters using
imitations of the tiny two-winged insects.

Midge patterns are tied and sold that don't remotely resemble a midge. Most of
the commercially available midge patterns are very colorful and flashy to attract
the angler rather than the trout. These work fine for newly stocked trout but in
Yellowstone Country, there aren't any stocked trout. Real midges aren't flashy
and colorful. In fact, most of them are dull colors such as shades of cream and
light green. There are also the red ones that imitate the blood worms but even
they are a rather dull red.  

There's a factor involved that does add what could be considered flashy. Midge
pupae reach the surface of the water to hatch with trapped bubbles of gas that
provides buoyancy. They can't swim as such. The tiny bubbles from this gas
does appear to make the pupae glitter.

Most of the species of midge larvae and pupae are segmented. By that, for
example,they may have alternate shades of light greens and darker greens, or
light creams and light browns. The segmentation is so subdued it's often difficult
to see with the naked eye. It's never highly contrasting colors that provide the
segmented appearance. The most difficult to match midge larvae, and some
pupae, are clear with alternating shades of light green or light cream colors.
"Clear" is difficult to match.

The midge pupae are not much different from the larvae in appearance. They
differ only because they have developed a small wing pad or fat looking darker
colored section near their heads.  They are the most important stage of life to
imitate because this is what the trout focus on eating during a hatch. The larvae
of most midge species spend their short life in the soft bottom, sand or decaying
leaves and vegetation on the bottom. Trout will eat the adults on the surface,
but nothing that compares with the number of pupae they eat during a hatch. I
will continue with the midge in the next article in this series.

Copyright 2011 James Marsh