Coeur D’alene River Fly Hatch Chart

Fly hatch chart for Coeur D’alene River in northern Idaho including fly hatch species, fly size, and peak months of activity based on historical data.

Coeur D'alene River Hatch Chart

Fly Hatch Chart for Coeur D’alene River in northern Idaho

Hatch sizes and dates will vary from year to year based on weather conditions, water flows, and temperatures. In some years, hatch may be more or less prolific. Typically the biggest indicator of fly hatches is when temperature reach above 50 degrees.

Fly HatchSizeDate
Western Green Drake10 -12Feb 1 - Mar 31; Aug 1 - Dec 31
Winter Stonefly16 - 18Feb 1 - Mar 31
Blue Winged Olive18-20Mar 1 - Apr 30; Sep 1 - Nov 30
Skwala14-16Mar 15 - Apr 30
March Brown14 -16May 1 - June 15
Little Black Caddis16 - 18May 1 - June 30
Golden Stonefly4 - 6May 15 - July 15
Salmonfly4 - 6June 1 - July 31
Carpenter Ant14 - 18June 1 - Aug 31
Japanese Beetle10 - 12June 1 - Aug 31
Pale Morning Dun14-18June 1 - Sep 30
Green Drake10 - 12June 15 - July 31
Yellow Quill16 - 18July 1 - Sep 30
Grass Hopper8 - 10July 1 - Sep 30
Mahogany Dun12 - 18Aug 1 - Sep 30
Tricos18 - 22Aug 1 - Sep 30
Spotted Sedges14 - 16Aug 1 - Sep 30
Flying Ants14 - 18Sep 1 - Sep 30
October Caddis6 - 10Sep 1 - Oct 31

Major Fly Hatches

Trout start surfacing in late winter early spring as the Coeur D’alene River comes to life with aquatic insects. Major spring hatches include midges, Blue-winged Olives (baetis), March Brown Mayflies, Stoneflies , and the Skwala Stonefly hatches the Coeur D’alene is known for.

As spring runs into summer a number of new hatches enter the scene including Salmonfly, Pale Morning Dun (PMD) Mayfly, Yellow Sally, Golden Stonefly, Green Drake, and caddis, which make up the majority of trouts’ diet during late spring early summer.

Other prolific hatches on the Coeur D’alene River, especially in the lower elevations, include Mahogany Duns, Yellow Quills, and Tricos. Important, but less prolific hatches include Golden Stonefly, Winter Stonefly and Little Yellow Stonefly.

While the Skwala Stonefly hatches are popular among anglers, they’re far less prolific and predictable than others. Anglers will find caddis hatches throughout the spring and fall with Little Black Caddis hatches in May, Spotted Sedge hatches in August, and the October caddis hatches in the late fall being the most prolific.

As with most of Idaho’s major river systems, terrestrial insects such as ants, beetles, and grasshoppers become a major food sorce for hungry trout come summer. Japanese Beetle, Carpenter Ant, and hopper imitations all get the trout biting early to late summer.

A few of the more effective flies to fish on the Coeur D’alene are sculpin and baitfish. Nymphing and fishing streamers tends to be the more effective method for trout fishing, although fishing dry fly is also productive during much of the season.