Mystery Bug

Emerger · Senior Member

Mystery Bug

SK60 · Senior Member

Its a fly! What kind is a different matter. Did you actually see them emerging or just swarming? Did they try to bite you or hover in front of your face? Was the weather pretty warm? The Wings are too long for a black fly and body is too stout for a midge, both of which could emerge from the river. If there was a lot of creekside foliage it could be a group of overwintering adults of some species that were stimulated to start to disperse by warmer weather. I have seen similar flies clinging en masse to streamside branches on Putah during cold weather. These� have a red blood pigment which is pretty spooky looking when you accidently crush them after grabbing the branch-looks like your fingers are bleeding.

Emerger · Senior Member

I've seen those bugs you mentioned on Putah too. There was that time that I grabbed a branch and pulled back a bloodied hand. A bit upsetting at first but I quickly recovered once I saw the culprit. wink

The weather was warm, although I've seen them there in cooler weather too. I didn't see them emerging but a quick seine of the river showed that they were on the surface and just below. My best guess is that they died in the water and were not emerging. They didn't hover in my face nor did they try to bite. They did like my waders and the back of my head/neck.

Otter · Senior Member

It looks like the famous caddis midge on the XXXX river. I have seen a few myself. The fly of choice is a fat mercury midge. Glass bead, black thread, silver ribbing and a peaxxxx thorax. Size 20.

Alpen Glow · Senior Member

It's�a Northern California Tsetse fly, once bitten you will become a trout bum forever, and think constantly about Fly Fishing. The only known cure is to Fly Fish as much as possible for the rest of your human life.