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.

A beautiful braided reach of the Sag River, with the Philip Smith Mountains in the Arctic National Wildlife Refuge (ANWR) in the background.

From the Sagavanirktok 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.

Olives

Martinlf

Moderator
Palmyra PA

Posts: 3047

Martinlf on Mar 14, 2021March 14th, 2021, 9:17 am EDT

We're seeing blue wing olives on local spring creeks, but on at least one the hatch has been sporadic so far. The first day I saw them there the weather was colder, in the 40's, and cloudy. Fishing was pretty good that day, despite a somewhat sparse and brief hatch. Then the weather brightened and got warmer, climbing into the 50's, 60, and finally 70's. Fishing was poor for everyone I talked with on those days, and folks said that like me, they didn't see many olives. It didn't help (in terms of the fishing) that it also got breezy. Some writers claim olives hatch equally on warm bright days and on cooler dreary days, or that even more hatch on sunny days everything else being equal. These folks say they just get off the water faster on bright warm days, so the fishing isn't as good, but my experience is that more olives (the early baetids anyway) actually hatch in cooler, darker, and especially drizzly or rainy weather. Can anyone shed some light on this topic?

"He spread them a yard and a half. 'And every one that got away is this big.'"

--Fred Chappell

Wiflyfisher

Wisconsin

Posts: 622

Wiflyfisher on Mar 14, 2021March 14th, 2021, 9:37 am EDT

Louis, I am with you on this subject. The best BWO hatches I have experienced have been in the Fall on the Madison River. The weather is always cold and crappy when the olives start to really pop.

John S.
https://WiFlyFisher.com