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

New KISS Bug Series - Part 9
Bugs 101

Terrestrial Insects - In General

Terrestrial insects are born and raised on land but often end up getting into the water. Wind and heavy
rainfall is most often the reason for this but they can also can get into the water by just making a navigation
mistake. Imitations of terrestrial insects are choice flies during the summer and fall seasons. You don't want
to be without terrestrial imitations from about the first of July until the end of the fishing season. Terrestrial
insects represent a large part of the trout's diet during the Summer months. They are especially plentiful in
the many meadows sections of the streams.

You would be hard pressed to find any place in Yellowstone National Park that didn't have plenty of ants. It
is one of the most important species of terrestrials to imitate. Ants, the Formicidae family of insects,  is one
of  the next most plentiful terrestrial insect found in the park. Fast rising water caused by heavy rains
is responsible for ants and terrestrial beetles getting into the water more than anything else. Ants live in
colonies and when they do get washed into the water, they usually do so in large quantities.

This includes the
flying ants. When flying ants show up on a stream, you will wish you had an imitation
because the trout will eat them with delight. They usually cover the water when they fall on a stream. When
they start falling on the water the trout normally go nuts eating them from the surface.

Grasshoppers are very plentiful in some places in the park. All of the streams that flow through meadows
have lots of grasshoppers. They exist on every stream in the park to some extent, even those that flow
through the timber sections of the park. The best time to fish the hopper imitations is when the wind is
blowing hard. That is not uncommon in the summer afternoons.

The meadows are the best areas to fish them. Remember to stay back away from the banks when you are
fishing the hopper. Thats where the fish are looking for them to fall into the water. We usually fish in an
upstream direction casting first right against the bank and then working the fly out on each sequent cast a
few feet at a time. You can cover a lot of water fast provided you make a lot of short upstream cast. You
will know when the trout takes you hopper imitation.

The most common terrestrial insect in the park is the beetle or Coleoptera. There are both aquatic and
terrestrial forms of beetles but here we are concerned with the terrestrial form.  Some species of beetles
can fly and these are more likely to get into the water than the others that cannot fly. Overhanging limbs of
trees, grass and shrubs provide the places for beetles to fall into the water.

Spruce Moths:
Spruce moths are insects that relate to evergreen trees. They can be very important during the late

Mormon Crickets:
These are huge insects that can be plentiful in Yellowstone National Park. They are really not crickets,
rather Katydids.

These insects can be plentiful during certain years. There are different types that appear at different time

Bees and Wasp:
Bees live in colonies. These colonies are usually very large and contains thousands of insects. They
sometimes fall into the water.

Copyright 2012 James Marsh