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3. Nymph Fishing and Behavioral Drift

Earlier this year I was doing some reading about behavioral drift and fish behavior. Something jumped out at me that I thought I ought to toss onto the table here and see what others think.

It seems to be a pretty well established fact that most behavioral drift takes place at night.
http://www.seattle.gov/light/environment/WildlifeGrant/Projects/MacroinvertebrateDrift.pdf

http://fwcb.cfans.umn.edu/courses/fw8459/Private/DriftandColonization08-4.pdf

It also seems that the day time behavioral drift (whatever little bit there is) seems to be relegated to the smaller bugs.

Hence, in the absence of actual hatch or pre-hatch activity, it would seem that the water is pretty devoid of actively drifting macroinvertebrates. It should then follow that when we fish nymphs during the day (in the absence of hatch related activity) we are in fact fishing "attractors". So carrying this argument forward another step one would ask, when we fish attractor dry flies we fish these gaudy, eye catching things - and they work. However, a lot of people still seem to search with more subdued nymphs. Why?

Of course the attractor type nymph concept probably accounts for the effectiveness of patterns such as the Prince, or that abomination - The Fly Formerly Known as the Prince, and Green Weenies, Copper Johns, Tellicos etc. It also probably accounts for the great success and older generation (like my Dad) had with wet flies like the Royal Coachman and Invicta. But what bothers me is why we keep trying to go towards truer imitations on nymphs, whereas it would seem that logic dictates we explore the attractor patterns in greater depth.

So while a great deal of attention has been paid to attractor dry flies, not much seems to have been done for their sub-surface counterparts (probably with the exception of streamers).

Wonder if we're missing something here, and whether the old-timers were onto something with their bright wet flies. Remember the Alexandra ( a gaudy wet fly with peacock sword and slashes of red and a silver body) was banned on chalkstreams for being too effective!

Thanks for starting an interesting discussion.



Non-hatch daytime drift density is usually low compared to dawn/dusk peaks in behavioral drift, but I wouldn't say it's devoid of drift. Plenty of insects of all sizes get knocked into the drift by accident. There are also some behavioral factors that could send them into the drift; for example, a large predatory stonefly nymph walking around on a rock could motivate many of its other inhabitants to release into the drift to escape. The scent of nearby upstream trout can do the same. So might competition or a lack of food on their particular rock. Insects are surprisingly alert and responsive to what's happening in their environment. The bottom line is that a drift net placed in a productive stream at any time of day is going to catch some bugs.



I think you're right that attractor nymphs are better most of the time. As long as the drift contains a wide variety of prey in similar abundance and isn't dominated by one extremely abundant species, I think attractors are the way to go. There's a balance to be struck in their design, though, between being eye-catching enough to grab the fish's attention from a distance versus being realistic enough that the fish judges them as possible prey from up-close. I usually start out with something very visible and then back off to something more realistic if the fish are noticing but rejecting it.

If there's reason to believe one species is disproportionately abundant and causing fish to be selective, during or slightly before a hatch, then I switch to a more subdued imitation.

Fascinating topic! I've come to the same conclusions, Jason. The only thing I would add is that during "hatch season" there is substantial daytime drift as insects prepare for emergence. Ephemerellids, baetids and some caddis are especially prone to this. At these times I've noticed nymphs fished deep in the column are far more effective if they contain a little flash while still matching the overall size, silhouette, and general color of the naturals. I generally start with the most abundant but also try patterns of the lesser species and let the fish decide. As the fishing gets shallower at or just before actual emergence, the opposite is generally true. I've had much better experiences with more subdued patterns most of the time.

As for the older patterns, I'd be wary of translating the effectiveness of a Beadhead AP or PT during PMD season to the old time attractors. The flies of our forefathers were cast to fish with a different level of sophistication. :)

Yes,very interesting discussion. On,alot of people still seem to search with more subdued nymphs.Why? Maybe cause, that's what we learned long ago.We learned how to make the real true art form nymph work for us, sometimes yes & no at times. But that goes with the fishing. Some of us just try to keep it simple & on that note that's a level of sophistication for a sport alot of us love. Hope that put some light on your ??. Keep it simple, you'll have more fun & bigger rewards.M.R.P.

Another "revolution" that has taken place is the (now) common use of tiny attractor nymphs, even in heavy water. Amazing catches are routinely made using these tiny things on rivers like the Sacramento, Madison, and the Box Canyon of the HF Snake; waters previously thought of as big fly water. They will usually out-fish the bigger stuff by a wide margin, and on fish up to 10 lbs! Even during Stonefly season, the smaller stuff works better. I now use the big stonefly nymphs mostly to assist in getting the little guys deep. Even when the Skwala and Salmonflies are hatching, the small nymph trailing behind will often out-fish the big imitations.

Kurt. To follow your thread a bit...One of the best nymphers I have had the chance to watch fish use to give me hell that my nymphs weren't small enough.

Through out the summer there is always small stuff crawling around. The newbie hatches that were deposited in the creek recently...As the fishing season goes on here in Michigan, post Hex, there are only small bugs left.

Spence

Exactly.

Spence, you gotta get a little dirty (wet) and go down after 'em. I like to see them in their own environment interacting with their peers. It has made a difference in my catch rate.

PS. Make sure you have waterproof fly boxes.

Feathers5, are you saying that to know behavioral drift you must be behavioral drift?

Thanks for the thread! Lots of great info here!

Yes, it just like in sport. You gotta' be the ball. It's a transcendental sort of thing.

Funny how when we get talking nymphs we get all transcendental. Can't one "be the dry fly"? I suppose with dries you can simply see the dang thing. Ohhhhhmmmmmm....

For the newcomers to the forum: Spence and Feathers5 were fishing a while back and Feathers5 took a little swim. Spence has been teasing him mercilessly in many a thread, so Feathers5 was suggesting that his swim was entirely voluntary (as he has done previously, in many differing analyses). This may add a bit more meaning to his comments:

Thanks Louis...:) When our friend is not taking a swim and getting next to them crawling critters, he's sitting on the bank of Spring Creek critiquing our fishing style...Or hassling Tony! :)

He will always be a part of my memories of the Little J...Some are wonderful. Some I'd rather forget...Like his hanging his Yogi Bear boxers on a tree limb to dry them off, after his dip, only to forget and leave them there...That one hurts! :)

Spence

It's improper to make fun of the American icon that is Yogi Bear. I'm out to look for a pic-a-nic basket, Boo Boo.