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Tricos

The Trico (genus Tricorythodes) is the smallest of the mayfly family usually a size 18-24.  They hatch from late July through the month of August and into September or the first frost of fall.  They’re of the crawler type and live mostly in rivers and favor slow water that has silt covered bottoms.  The nymphs are not important to trout but the duns and spinners are.   Males have black bodies and thorax with clear wigs and the females have grayish or olive bodies with a black thorax and clear wings.   Trico’s have 2-3 emergences a day.  The males hatch in the evening and females hatch in the mornings.  The males will spend the night hanging out in stream-side vegetation waiting for the females to emerge.  The male trico will spend the night as duns and turn to spinners in the early mornings where females turn to spinners almost immediately after hatching.  In the mornings the males wait around in the trees, shrubs, and grasses until the females hatch.  As the females begin to emerge the males will join them and clouds of tricos begin to swarm looking like a cloud of smoke over the river.   This event is where males and females fly around in great masses searching for their mate.  After mating the females will head to the water to lay eggs as the males will just fall in the water and die.  This creates a ridiculous amount of food for the trout to feed on. Males usually die first and the females a short time later.  It’s important to the angler to take note of timing of these events as the males are darker and slightly larger bugs and the trout will get extremely selective when eating Trico’s. It gets really tricky when the trico’s have second and third emergences all within the same morning session. The trout will switch from eating male spinners to female spinners, then to male duns and females duns, then back again to male spinners and female spinners.  This sequence is what normally drives the fly fisherman INSANE and can be very difficult to master.

trico trico1 Tricopattern

During the hatch it’s usually best to fish a bigger dry fly that you can see such as a Parachute Adams, Lime Trude, or Royal Coachmen, and follow it with a trico spinner or dun pattern.  We really like to focus on the male spinners early in the hatch as the trout really key in on them as they are the first to die.  Most of the time the males aren’t perfect spinners as they’re death is usually results in a crash landing.  With that being said a black RS2 or a sunken trico will usually do the trick especially if the fish seem to be shying away from surface. Later in the morning we’ll switch to the female spinner as they start to die and fall into the water after laying eggs.

To fish this hatch you must use a 9-12 ft 5-6X leader.

Here in North Park the Trico hatch is very good on all stretches of the North Platte from Walden through North Gate Canyon.  Our spinner falls are generally from 9am-noon and are best on days the wind is not blowing too hard.  The best dry fly activity is during the spinner fall.  On days where weather and water temps are perfect this hatch can last until 2-3 in the afternoon but is usually done for by noon

A few flies we recommend are:  Spinners #18-24 Poly Wing Trico Olive or Black, Organza Trico Spinner Olive or Black, CDC Trico Spinner Olive or Black.  Duns: CDC Thorax Emerger Black, CDC Thorax Dun Black, Cannon’s Bunny Dun Trico Black….