When fish are feeding on small insects, they must eat a lot of them to fulfill their dietary needs. Possibly the best example of this happening in New Mexico is on the San Juan River, where trout feed regularly on the ever-abundant very-small midge insect.

The midge is incredibly small, only the size of a couple of flakes of pepper. They are so small that you probably will not see them floating in the water unless they are grouped in a cluster. You will notice them after a day of wading or floating in a drift boat. If you look closely after being in the water for a few hours, sometimes you will notice hundreds of tiny midges stuck to your gear.

The emerger is a midge fly resembling the transition that occurs at the water’s surface as midge transitions from pupae to adult. These flies are often used for fishing from the water’s surface down to three-feet deep.Subsurface midge flies, imitating the larvae and pupae stages, are often fished at two- to six-feet deep. The emerger is a midge fly resembling the transition that occurs at the water’s surface as midge transitions from pupae to adult. These flies are often used for fishing from the water’s surface down to three-feet deep. The depth at which any of these flies are used is dependent on the overall water depth and at what level fish are prevalent in the water column. A number six split-shot weight positioned a foot above your fly is an excellent way to achieve depth.

A strike indicator placed on your fishing line five- to six- feet above your fly serves as an indicator for when a fish eats your fly, much like how a traditional bobber works. If the water is only three-feet deep, then the indicator should be placed approximately three-feet above your fly and so on.

Dry fly or floating midge flies are often tied to imitate a cluster of adult midges grouped floating on the water’s surface. These flies work best when you can visually see fish rising to eat from the water’s surface. Floatant is used to keep your fly from sinking.

When using these techniques, the presentation of all midge pattern flies is very important in becoming a successful angler. You want your fly to look as natural as possible. To do so, one must master the art of mending and working with a light pound-test fishing line.

My good friend Chris Gallegos is a professional angler on the San Juan River. He has been teaching me for years the art of fly fishing. He says there are three main components to mastering the art.

1. Use light tackle. Chris prefers three-weight fly rods and two- or three-pound test fishing line. Light pound test line is not as stiff as a heavier pound test and therefore allows small flies to move more naturally while being fished.

2. Use little flies when imitating the midge. Midges are so small that even the smallest hooks are not smaller than an actual midge. Chris prefers size 30, 26 and 24 barbless hooks.

3. Master mending your fishing line. As your fishing line and fly float downstream, chances are that your line and fly will float at different rates. Varying speeds in the current can vary across sections of the river. Mending your line is to adjust for these variances, allowing your fly to continue at its natural rate, unencumbered by pulling from the line that it is attached to. For instance, if your line is traveling slower than your fly, then the line will pull upstream on the fly, causing a dragging effect because the fly is not able to travel at the currents rate. Contrarily, if your fishing line is moving faster than you fly, then the line is pulling your fly downstream at a rate more quickly than where the fly is positioned in the river. Both instances cause the fly to present unnaturally and many weary trout will pass on the out-of-sorts fly. Mending is, after the cast, purposely flipping a curve into your line that enables the fly to drift naturally. Here is a YouTube video by Fly Fishing Down Under that demonstrates the application of mending.