This is the Dun Variant, Slate Drake, Leadwing Coachman, and
the White Gloved Howdy. If the multi-naming of the same fly
doesn't confuse a person, those who really know say Isonychia
sadleri and Isonychia harperi are just later broods of Isonychia
bicolor. We have noticed for years there was a late June hatch
and a August thru October one, but of a smaller size. This is what
one would expect of a bivoltine species (two broods a year). The
later broods of all multi-brooded species are always smaller
as far as I know.
This nymph is classified as a swimmer, it sits on a rock and strains
organic matter out of the drift with its front legs. It feeds as a filter
feeder and as a predator on other nymphs, diptera, and caddis larvae.
It is a tremendous swimmer, able to swim upstream in the faster
currents, darting like a minnow. I wonder if smaller Muddler
Minnows that are fished with a twitch are sometimes mistaken
by nasty old brown trout for the nymph.
This mayfly lives in highly oxygenated moderate-to-fast freestone
rivers in the rocky riffles. Other rivers will have a few strays but
the majority reside in the fast freestone streams. Some tail-water
fisheries, like the Delaware, grow this fly like mid-west farmers
grow hogs, a lot of them and all season long.
Now comes the controversy. Almost all the entomologists routinely
write that this species doesn't hatch in mid-stream but crawls up on
a stream side rock to hatch. The problem is too many of these experts
write articles based on what others have written rather than spending
time on the stream fishing the hatch. I see so many duns during the
hatch in the air and so few shucks on the stream side rocks and weeds.
It's hard to reconcile. I have seen them come off mid-stream on a regular
basis, and I'm not alone.
Now we know why Ray Drolling's emerger works. His "XT" duns
and spinners have always had merit. (See Fly Fisherman magazine's
volume 8 :69-77, and Boyle and Whitlock's 1978 The Second
Fly Tier's Almanac. Mayflies by Knoop and
Cormier, (p-88) quotes Dr. George F. Edmunds, Jr.,". . . that open-water
emergence of this nymph is not uncommon." I would say Edmunds spent some time
on the stream.
This nymph swims with an up-and-down motion like all mayflies,
while stoneflies swim like a fish, which is side to side. This fact
should be more than just an amusing aside to the astute fly fisher.
How do we tell the difference between the dun and spinner? It's really
easy. Like most spinners the wings are clear, the dun has slate-colored
wings. My, it's amazing how many big fish will come up to the spinners
that lie spent on the surface, and contrary to the literature how many
good fish will attack the emerger/dun.
The nymph has always fished well. It's a 3 tailed, hot dog shaped thing,
with gills all over the abdomen. Brownish-black would describe its
color. It has a light colored stripe down the top. This stripe is a
distinctive characteristic. Tie it in a fat 10-12 size and fish it with
a strong twitch. It darts like a minnow. I tie the body with peacock
herl and the tail with 3 tapered peacock herl tips. The stripe I represent
with a thin strip of silver mylar. A Mustad 9672 hook weighted for
the deep runs and un-weighted in the skinny water says it all. A
3-4x long hook is the game.
The emerger/dun is best represented by the XT tie. An inch or so
long tie with a 14 hook. The body is an extended deer hair thing
covered with either peacock herl or dubbing that represents such. A
deer hair wing case or other floater (foam or such in nylon stockings)
allows the emerger to float in the correct near vertical position.
Other ties are popular, especially in the Adirondiacs. Art Flick's
Dun Variant and the parachute tie have their adherents. See the
citations for the correct tie on the XT winner, sorry no scanner,
or digital camera here. I have seen the nymph/emerger and the total
length can be almost two inches long. I've watched it on land, but
never had the courage to fish a fly that size. Maybe I can talk Les
Young or Rich Colo into trying the long tie. I have to drive several
hours to get to the hatch and now really can't until my feet heal.
I tie the spinner with dark turkey biots and an antron wing. The tail
is male pheasant center wing barbs that are seen as real brown. I tie
5-6 barbs for the tail. When I remember I tie one wing upright and
one wing flat on the waters surface. A 12-14 tie. Caucci and Nastasi's
compara-spinner or Wetzel's White-Gloved Howdy in a 8-10 are
what a lot of smart fishermen use.
It's a nice event. Big flies when all the rest we see are so small that
a microscope is needed to see them. Flies that are 8-14 in the midst
of 18-20's. No wonder we love them.
I have tried a greenish egg pattern on an 18 short shank wide gap
hook with an 8 inch leader that is tied to the bend of the hook of the
spinner. The thinking was that since the spinners on occasion drop
their eggs from a foot or more in the air, an egg fall might produce.
I have not fished the egg fall well. Try it, maybe I just didn't fish
Those who fish the Delaware are certainly more informed about the
hatch than I. There is an old camp song that in part asks what did Della
wear. The answer was a new jersey. A more appropriate response
might be the slate drake all season long.
The trivia question for the day is why Charles Wetzel called the
spinner the White-Gloved Howdy. The answer is that the female spinner
looks like it is extending its white hands/feet in a 'howdy' greeting.
Les Young, Ron Koenig, Rich Colo, Ron Kusse among others on
this sight are more knowledgeable with regards to this hatch than
I am. I just couldn't hint or badger them into writing the article. Ask
them in the Chat Room. They fish the hatch all year long, year after
year. They know. I'm lucky to drive to the hatch twice a year.
Ask them in the Chat Room here on FAOL. They will let you know
when and where. It's sure nice at 11 PM to get a report of what
happened on the stream that day.Old Rupe
For the tying method on the one wing up flies, click
Special credits: Photographs courtesy of Al Caussi and Bob Nastasi,
from their book Hatches II published by Lyons Press.