Fly fishing using nymph imitations is, at least in my opinion, the
most productive method available to today’s river anglers - and
pretty darn effective in still waters too.
It has been estimated that 80 to 90% of a fish’s feeding activity
occurs near the bottom of a lake or river. This, surely, has significance
to an angler. It is, therefore, worth looking into the flies and methods
of fishing utilized to get down to where the fish are most actively
The predominant food items of fish are mayfly, caddis fly, and stonefly
nymphs. There are too many specie of each to go into a lot of detail
here, suffice it to say that they are an extremely important food source.
These live among the bottom weeds and rocks, for up to four years in
the case of some stoneflies, and are readily available food items throughout
Most of these are poor swimmers and, when dislodged from their normal
habitats at the river bottom, drift freely with the current, hoping
to find something to grab onto and return to their preferred habitat.
It is at this time that they are available to the trout.
Different specie have different hatching methods. Some swim to the
surface, some float to the surface to emerge into flying adults, and
some creep along the bottom to the rivers edge to crawl onto shoreline
vegetation to emerge. It is during this migration, and the emergence
stage, that nymphs are most vulnerable to trout, and they feed voraciously
on them from the time they leave the bottom structure until they have
completed the emergence and flown away.
Some of the flies used to represent mayflies and caddis flies are:
gold ribbed hare’s ear, 52 buick, squirrel tail, prince, and pheasant
tail to name just a few. There are also a legion of flies that represent
the various stonefly varieties.
Probably the best way to fish most nymph patterns is with a floating
line, a fairly long leader and a strike indicator.
Strike indicators come in many forms and most work quite well. The
key is to have one large enough to stay afloat with the weight of the
fly, yet not so large as to cause troubles casting or in controlling
the drift. For small flies a 2” piece of brightly coloured yarn
that has been sparingly treated with fly floatant works quite well.
Larger and heavier flies need a more buoyant indicator. I use a ‘loop-to-loop’
connection system for my leaders, so the yarn is very easily trapped
between the two loops, and passes easily through the tip top guide when
using a very long leader (longer than your rod- 12 or 15 feet).
The fly should have enough weight to travel right at the bottom, with
an occasional tick as the fly hits a rock being transmitted up the line
and through the rod to your hand, and you should occasionally catch
bottom. If you don’t, you’re not deep enough.
Depth is controlled by the weight of the fly and additional weight
added to the leader in combination with leader length, and the distance
between fly and indicator. Depending on current speed this distance
is usually something about 1 ½ to 2 times the depth of the water
being fished, necessitating frequent adjustments for different pools,
runs, and riffles.
Cast from directly upstream to about 45o up and across. As the fly
and line approach, begin lifting the rod tip, and arm if required, until
it is straight up and there is very little line remaining on the water.
At this point, the fly should be about even with you. As the line travels
downstream, below you, lower the rod tip until it is touching the water,
keeping pace with the movement of the fly. Allowing the fly to be pulled
from the bottom by the current, thus imitating an emerging nymph, often
triggers a strike. Whenever there is the slightest pause or change in
momentum of the indicator set the hook- it may well be a fish.
This can be a very tiring method as there is a lot of shoulder movement
and holding of the hand in the air, but it is well worth the effort.
There are thousands of mayfly and stonefly genera, but it is not important
to know them all, nor is it important to know their full scientific
name. When you get to a piece of water, take a few minutes to pick up
a few rocks and check out the nymphs that are clinging to them.
The nymph you see in highest numbers would be a good pattern to begin
with. Imitations should be about the same size, and colouration, although
it is usually safe to go a bit bigger. If you carry mayfly nymphs in
brown, tan, and gray in sizes ranging from 10 to 18 you are well prepared.
Stoneflies in black and golden brown in sizes 4 to 10 are common.
If you have never tried nymphing you are missing out on some good action.
It is not as visually exciting as dry fly fishing, but it can sure be
a lot more productive. Remember that the emergant adult, or the egg
laying female adult are only two very short events in the total life
cycle of the insects.
P.O. Box 2440,
Banff, Alberta T1L 1C2
Phone: (403) 760-1133
Copyright Alpine Anglers