Matching What's Going To Hatch
Just as important as matching the hatch
Copyright 2013 James Marsh
Premiere Issue August 2013
will admit that I get a little bent out of shape when someone makes a statement about me like "Marsh is strictly a match the
hatch advocate". That's true in one sense but very misleading in another. I'm more of a "match the most available and
plentiful food that is easiest for the trout to acquire" advocate. It is just a fact that most anglers think only in terms of matching
Before I continue with this article, let me point out that although anglers use the word "hatch" for emerging aquatic insects, they
actually hatch from eggs. When I refer to matching the hatch, or matching what is about to hatch, I'm referring to matching aquatic
insects emerging into the adult stage of their life.
The main object of this article is to point out that it is usually more important to match what is "going to" hatch than what has
already hatched. When the nymphs and larvae of aquatic insects move out from their normal hiding places to hatch, they are
usually readily available and accessible for hungry trout to eat. The time they require to fully develop wing pads and actually
emerge into the adult stage of life varies, but as a general rule last from a couple or three days to as long as a couple of weeks
or more. It depends on the species of insect, the water and the environmental conditions. This is always the easiest time for trout
to eat them.
Often anglers don't recognize a hatch until it is too late to do them any good. When they begin to see lots of the adult insects
either flying around or in the trees and bushes along the banks of the stream, it often indicates the particular species of insect has
already finished hatching. Most aquatic insect hatches only last from an hour, to two or three hours, on any given day. When
anglers begin to see lots of grown insects, that usually indicates the hatch has already taken place that day. It may even indicate
the hatch has completely ended. In these situations, the angler has to wait until the adults mate and deposit their eggs before they
return to the water. Although I have seen trout jump completely out of the water to eat a flying insect, they don't normally eat the
insects that are flying around or in the bushes.
Too much emphasis is placed on matching the hatch versus matching what's about to hatch. Consider the three most
common types of aquatic insects anglers imitate - stoneflies, mayflies and caddisflies.
Most all stoneflies crawl out of the water to hatch. You either match the stonefly nymph or you wait until the female adults return to
the water to deposit their eggs and match the adult female stoneflies. Trout eat far more of the nymphs than the egg laying female
Most mayflies hatch in the water. They can emerge on the bottom or somewhere below the surface, but they usually emerge in the
surface skim. The nymphs of a few mayfly species crawl out of the water to hatch but most of them emerge in such a manner
that the trout can easily acquire them. During the period of time they are struggling to shed their nymphal shucks, they are very
subject to being eaten by trout. Once the nymph loses its shuck and the dun's wings are dry enough to fly, they quickly depart the
water. This usually happens within a few seconds, not minutes. When you are imitating a mayfly dun, you are only imitating it for a
few seconds of its life. Mayfly duns do not return to the water. The only time you are matching or imitating hatching mayfly duns is
during the time it takes them to depart the water. Mayfly duns do not return to the water. They change into what anglers call mayfly
spinners. The mayfly spinners don't return to the water until they mate and the males happen to fall in the water, or the females
return to deposit their eggs in or on the water. They may drop them from above the water and never return to the water unless
they happen to die and fall on the water. Mayfly spinners are usually drifting in or on the water in a spent position, or with their
wings in a flat (spent) position.
Unlike stoneflies and mayflies, caddisflies undergo full metamorphosis. They emerge into their adult stage of life from pupae. This
happens anywhere from the bottom of the stream to the surface. During the period of time the adults are struggling to emerge
from their pupae, they are easy prey for trout. Like mayfly duns, adult caddisflies also depart the water as soon as their wings are
dry enough to do so. They don't return to the water until the females begin to deposit their eggs. This may be as long as a few
days after they have hatched. Trout eat far more caddisfly pupae than adults.
In other words, if you think of matching the aquatic insects only in terms of matching the hatch, meaning imitating the mayfly dun,
or the adult stonefly or caddisfly, most of the time your completely missing your best opportunities to catch trout. You should start
thinking in terms of matching what's about to hatch as well as matching the hatch.
the hatch. That works, but only for a very short time.