What's happening here?

This topic is about the Caddisfly Genus Brachycentrus

This prolific genus includes the popular eastern early-season Apple Caddis and Grannom hatches. Their life cycles are ideal for the fly angler, and every stage is frequent trout prey.

Note that this species changes color dramatically after it emerges, and imitations of egg-laying adults should be a different color from imitations of emergers. Emergers have pale blonde, almost off-white wings and bright green bodies, while the egg-laying adults have light brownish gray wings and medium green bodies. Read more...

Brachycentrus (Grannoms) Caddisfly Pupa (10 Pictures)

Brachycentrus appalachia (Apple Caddis) Caddisfly Adult (13 Pictures)

There are 3 more specimens...

The Discussion

Post Reply

Troutnut	June 5th, 2007, 9:05 pm
The Admin Fairbanks, AK Posts: 2020	Check out the two streamside pictures on my Brachycentrus page. I found these clusters of dead grannoms in a few different spots along a Catskill river on May 12th, while many members of (seemingly) the same species were in the air laying eggs and occasionally falling spent and being eaten by trout. Have you ever seen these clusters? What's the explanation?
	Jason Neuswanger The Troutnut

Taxon	June 5th, 2007, 11:24 pm
Site Editor Mercer Island, WA Posts: 921	Jason- I would speculate that they were exclusively males, which with no further function in life, seek the company of other similarly underappreciated males, and lay back on a warm surface to expire. Can there be any other likely explanation?
	Roger Rohrbeck www.FlyfishingEntomology.com

Troutnut	June 6th, 2007, 7:30 am
The Admin Fairbanks, AK Posts: 2020	Perhaps this species swarms together on the rocks to mate, and when they're done the males stay there and die while the females fly off to lay their eggs? Seems a little more likely than "seeking company," but you're probably on to something.
	Jason Neuswanger The Troutnut

Quillgordon	June 6th, 2007, 8:39 am
Schuylkill County, PA. Posts: 109	I think they were waiting for Jason to photograph them.... LOL. Perhaps they will survive to see themselves in the next issue of 'Entomology Today'........... Where is my fishing gear & camera ??? John...
	Flyfishing is a state of mind! .............. Q.g. C/R........barbless

GONZO	June 6th, 2007, 8:44 am
Site Editor "Bear Swamp," PA Posts: 1636	Jason, I'd check the flow regime on the days prior to your photos. Knowing the fluctuations on that tailwater, lower release levels may simply have deposited accumulations of the dead adults in certain areas. (This might even explain why most are on their backs.) As another take on the topic, I was reminded of LaFontaine's recounting of a Charles Wetzel observation about green sedges. Quoting Wetzel about the egg-laying habits of the females, LaFontaine writes: "Now and then the flies would congregate in a ball about one inch in diameter, rise to the surface, then float downstream, when the ball would break up." This behavior is probably unrelated to the grannom accumulations you photographed, but I thought I'd offer some alternatives to Roger's (facetious) "abandoned lover's club" explanation.

Troutnut	June 6th, 2007, 9:04 am
The Admin Fairbanks, AK Posts: 2020	Jason, I'd check the flow regime on the days prior to your photos. Knowing the fluctuations on that tailwater, lower release levels may simply have deposited accumulations of the dead adults in certain areas. That would make sense; in fact, the way they're laid out, it almost seems like it has to have been done by water. I'm doubtful that the water was high enough, though. There was slight spike the day before my visit, about 200 cfs vs 150 cfs, or a couple inches of gage height. I doubt it would have brought the water high enough to deposit the flies here, and they didn't seem to be in the most likely locations for eddies if the water was high enough. I wish now I had taken another picture from several feet back. That may still be the explanation, but I would be more inclined to believe some behavioral alternative if one makes sense.
	Jason Neuswanger The Troutnut

Quick Reply

You have to be logged in to post on the forum. It's this easy:

Related Discussions

Title	Replies	Last Reply
Re: egg sack color In the Mayfly Family Heptageniidae by LittleJ	3	May 20, 2007 by LittleJ
Re: Need to identify. In the Identify This! Board by Sayfu	6	Aug 19, 2011 by Sayfu
Beautiful yellow drake In Female Ephemera varia Mayfly Dun by GONZO	0
Re: Question In Female Claassenia sabulosa Stonefly Adult by Flymonster	2	Sep 10, 2011 by Sayfu
Re: White Mayfly ---- Euphron leukon? In the Identify This! Board by JumpNotZero	1	Sep 9, 2008 by GONZO
Re: itzy-bitzies! In the Identify This! Board by Wiflyfisher	6	Aug 9, 2007 by Martinlf
Re: Humongous Erie Steelhead In General Discussion by Wbranch	7	Apr 1, 2009 by Wbranch
Re: Why mayflies dance In General Discussion by Troutnut	5	Dec 5, 2007 by Martinlf
Re: Need help with id of a mayfly In the Identify This! Board by Deane	3	Jun 30, 2010 by GONZO
Re: Boiling Springs Run In General Discussion by Wbranch	6	Dec 7, 2009 by Martinlf

Troutnut Forum > Fly Hatch Talk > What's happening here?

This topic is about the Caddisfly Genus Brachycentrus

The Discussion

Quick Reply

Related Discussions

Troutnut Forum
>
Fly Hatch Talk
> What's happening here?