Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York

Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

I like this one. Glacial river, taiga, tundra, and the perpetual ice cover of a massive high ridge dozens of miles away in the Wrangell Mountains.

From the Copper River in Alaska

Stream photos

Featured on the forum

Re: Trico emergers
In the Mayfly Genus Tricorythodes by Bwoklink (Martinlf replied)

Re: Trico Tips
In the Mayfly Genus Tricorythodes by Martinlf

Re: UV spectrum and trout
In General Discussion by Martinlf

Re: closing the gender gap in flyfishing
In General Discussion by Konchu (Smallflyguy replied)

Re: Fishing Kupa River, Slovenia
In Fishing Reports by Slocum (Fish1 replied)

Onocosmoecus (Great Late-Summer Sedge) Caddisfly Larva Onocosmoecus (Great Late-Summer Sedge) Caddisfly Larva

Lateral view of a Onocosmoecus (Limnephilidae) (Great Late-Summer Sedge) Caddisfly Larva from the Yakima River in Washington

This specimen keys pretty easily to Onocosmoecus, and it closely resembles a specimen from Alaska which caddis expert Dave Ruiter recognized as this genus. As with that specimen, the only species in the genus documented in this area is Onocosmoecus unicolor, but Dave suggested for that specimen that there might be multiple not-yet-distinguished species under the unicolor umbrella and it would be best to stick with the genus-level ID. I'm doing the same for this one.

9 Recently Added Photos

27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.

Troutnut is a project started in 2003 by salmonid ecologist Jason "Troutnut" Neuswanger to help anglers and fly tyers unabashedly embrace the entomological side of the sport. Learn more about Troutnut or support the project for an enhanced experience here.

Caddisfly Species Brachycentrus occidentalis (Mother's Day Caddisflies)

Gary LaFontaine tells the story in Caddisflies of how this species came to awareness through rumors of a widespread, intense hatch of an undentified brown and green caddisfly throughout the West. He traveled across the West collecting these flies and determined that they were Brachycentrus occidentalis.

Where & when

Time of year : Late April and early May

In 36 records from GBIF, adults of this species have mostly been collected during June (33%), May (31%), April (22%), and September (6%).

In 15 records from GBIF, this species has been collected at elevations ranging from 66 to 19029 ft, with an average (median) of 5367 ft.

Species Range

source

Map of specific collection sites

Hatching behavior

Time of day : Daytime

Start a Discussion of Brachycentrus occidentalis

References

LaFontaine, Gary. 1981. Caddisflies. The Lyons Press.
Swisher, Doug and Carl Richards. 2000. Selective Trout. The Lyons Press.