When trout fishing, the environment is an ever-changing world and versatility in fishing methods is advantageous to the success of an angler.
One of the many techniques that we use to target trout at Chile West is to swing flies. When wade fishing is available, this method can be very effective for hunting up bigger fish using a streamer pattern on a sink tip.
Unlike nymphing or dry fly fishing where it is advantageous to start from below and work up, when swinging you start in at the top of the run and work down.
One thing to keep in mind is the size of the fly and the density of the sink tip. Use a tip with a sink rate appropriate for the depth and current speed of the run you are fishing. A multi-tip line is a great system to have when swinging different types of water.
As far as the size of the fly, think about a small minnow swimming in the river. In heavy water a small fish would tend to be swept downstream as it would not be strong enough to swim against the current, but a larger minnow would. As the minnow finds its way to softer or slower water it would be able to swim more easily and escape harms way.
So with this said, cast the fly across the current with a slight angle to 45 degrees downstream. As the fly line hits the water, make an upstream mend in the line and hold the rod tip out in front. As the line begins to straighten out the fly will begin to sink and literally “swing” across the current as it moves downsstream through the hole. It is not always necessary to make an upstream mend; this depends on current speed, depth of the run, size of the fly and sink tip. At times, you may even need to mend downstream, putting belly in the line – for instance if the current is too slow to swing the fly.
This can be explained as filling a sail with wind to push a boat. By mending a belly into the line, you fill the line with current and this will push the fly line and pull the fly across and through the hole. Even stripping the fly at the end of the swing can be effective.
Many times a fish will follow the fly, observing, until taking it or rejecting it. Generally when swinging flies you don’t see the fly or the fish. One can only imagine and guess what is taking place under the surface.
Think about being a minnow in a big river, with big fish that want to eat you!