Mystery caddis

Discussion in 'Fly Fishing Entomology' started by Sean Beauchamp, Jun 30, 2014.

  1. Sean Beauchamp

    Sean Beauchamp Hot and Heavy at yer 6

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    Just had a crazy dry fly session on a west slope cascade stream. I got to a favorite run about 1pm in full direct sun to find a frenzy in progress. Rainbows were going airborne eating on the surface as a deep riffle pushed onto a rip rap bank. Gray drakes were buzzing around over head, and large brown caddis were laying eggs and emerging everywhere along the deep bank and I immediately was hooking up on a size 10 gray drake pattern. After action slowed down I took a few minutes to take in what had just happened when I realized the drakes were being blown upstream from the long slow deep stretch and they actually weren't on the water at all. It was the caddis the fish were going nuts for. They were 3/4"+ long and brown/tan. With the wind and precarious rip rap wading I was never able to catch one for close examination and in my excitement I didn't think to pick up any of the shucks piled up in the eddies. I did notice that when they emerged, within seconds they were in flight and when they laid eggs they would dap a couple times before sticking where they would float for 3-5 seconds before going airborne again. My drake pattern was the right size and must have been close enough in color to warrant attack. Anyways I've never seen that caddis hatch before and I'm dying to go back and capture some. I've been looking online but I'm not seeing a midday hatch like that with larger caddis and I'm a bit stumped as to what they were. Any help?
     
  2. Taxon

    Taxon Moderator Staff Member

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    Hi Sean-

    I've been looking online but I'm not seeing a midday hatch like that with larger caddis and I'm a bit stumped as to what they were. Any help?

    Well, based on your description of their behavior, you were apparently observing ovipositing females, and not emergence activity. However, if I were to take a SWAG based on the size and the wing color, it would be Rhyacophila. Have you looked at my WA Aquatic Insect Emergence Chart? That's a good place to start. ;)
     
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  3. Sean Beauchamp

    Sean Beauchamp Hot and Heavy at yer 6

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    I looked at your chart, amazing work there! It was tough for me simply because I never got to examine one up close and personal and I honestly know very little about the local entomology I know the basics but as far as ID on specific species of caddis I'm lost. There was a ton of insect activity with what looked like several colors of caddis some them had a rusty red color to them (wings) while others were definitely brown. The olive green color of the link you sent me is throwing me off I don't think the naturals were olive is it possible to see a lot of variation in color depending on the stream. 16mm size seems right they were a substantial caddis (still smaller than oct caddis).

    Thanks for the reply!
     
  4. Sean Beauchamp

    Sean Beauchamp Hot and Heavy at yer 6

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    I thought some were emerging from the looks of it but it's totally possible I was misinterpretating what I was seeing. It sure looked like they were popping up out of the film in the small eddies tucked along the bank.
     
  5. Taxon

    Taxon Moderator Staff Member

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    Sean-

    There are two photos in the link I posted. The photo on the left with the body you describe as olive green is of a typical Rhyacophila larva, and the photo on the right with the brown wings is of a typical Rhyacophila adult.

    The larvae of genus Rhyacophila can vary in color depend on which species they are. Although the majority will be some shade of green, not all species are. However, the adults of genus Rhyacophila will typically have brown wings.
     
  6. Sean Beauchamp

    Sean Beauchamp Hot and Heavy at yer 6

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    Well I was able to capture and examine a good variety yesterday afternoon/evening. The bodies of the larger ones were a dark cinnamon brown and about 12mm long with brown mottled wings. Some had more of a rusty red to them that even showed in the wings and especially attennae. A handful of yellow sallies and a solid showing of gray drake spinners. Pretty amazing bug to handle and examine. And the fish thought so too. Shortwing stone shucks everywhere. It's safe to say summer has begun.
     
  7. Taxon

    Taxon Moderator Staff Member

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    Good work, Sean. Those would have been Hydropsyche.
     

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