Adrian Freer is the author of books on reservoir fly fishing, fly dressing, trout fly patterns, religious topics, children's stories and poetry.

THE IMITATIVE APPROACH TO RESERVOIR FLY FISHING

 

© 2013 Adrian V W Freer

 

The writer explains why fly anglers should perform an autopsy on every fish they catch

 

In this article I intend to explain my philosophy regarding to reservoir fly fishing, because that will shed light on how I set about catching trout.

 

First and foremost I am a nymph angler who enjoys catching fish using the imitative approach of trying to identify what the trout are taking, and then attempting to catch them by using a suggestive or imitative representation. I am continually experimenting to try and improve my techniques rather than settle on a successful method which is repeated over and over.

 

The longer I fish, the more I enjoy the challenge of taking trout on representations of natural creatures, rather than simply catching a lot of fish for the sake of a limit bag. I think that deceiving the fish into taking, rather than using random methods or stimulating the trout’s aggression or its territorial instincts, gives far greater satisfaction. I hope I can persuade those of you who do not share my philosophy to at least give the method a try!

 

PERFORMING AUTOPSIES

 

Performing autopsies on every single fish that is caught is therefore part and parcel of my regular fish catching routine. I don’t know how many of you carry a marrow spoon, but I suggest that you do. For my kind of fishing it is essential. I must have carried out thousands of autopsies and photographed many hundreds over the years.

 

The importance of carrying out autopsies was first impressed upon me by an incident which occurred many years ago. The trout were seen to be feeding near the surface in what appeared to be a classic buzzer rise but, in spite of fishing a team of buzzer pupae just below the surface, the fish refused to cooperate. After more than an hour a chance fish was caught and spooned and the autopsy revealed that buzzers were not the source of attention after all, but rather terrestrial beetles, some of which were still floating in the examination dish. A change of tactics to foam beetles fished right in the surface film resulted in a take every few minutes! Without the spooning it would have been so easy to carry on, not get a take, and then complain about the fish being perverse. That single incident changed my approach forever and it has undoubtedly put many hundreds of extra fish in the bag for me over the years. It is sometimes all too easy to misread what is going on by observation alone and draw erroneous conclusions, but when the food is taken from the stomach of the trout it is impossible to make such a mistake. Fly fishing has very few absolute certainties – but this is one of them!

 

Looking at the result of this single sweep of the collecting net from the shallows at Thornton Reservoir you will gain some idea of the wealth of food items available to the trout: snails, cased caddis, damsel larvae, corixae, freshwater louse, bloodworm, beetles, a lake olive nymph, a leech – and there were even two newts – you will understand why they pack on weight. It is up to the thinking fly angler to discover exactly what the trout are taking and then find an artificial fly to replicate it.

 

Let me say at the outset that, as a result of my own findings, as well as the findings of others, I have come to the conclusion that what I call ‘suggestive representations’ of the food items are far more successful than what could be called ‘exact imitations’. That is, in itself, a very significant observation.

 

THE SPOONING PROCESS

 

I will explain the process for carrying out an autopsy for those who have never performed one before, although it is quite straightforward. After the fish has been caught and despatched humanely, the marrow spoon is carefully inserted in the fish’s mouth and pushed down the throat until a slight resistance is felt. After a little practice this place can be found quite easily. The spoon is next rotated two or three times to collect what is in the trout’s stomach and then carefully withdrawn with the spoon facing upwards. It can be useful to make a mark on the handle if this position cannot easily be identified. The evidence of what the trout has been taking prior to capture will then be plainly visible. Providing it is done correctly there will be no blood or mess involved. The whole process takes only a few seconds and in view of the wealth of vital information it will disclose it is always time well spent.

 

If the spoon is full a repetition of the procedure will be necessary to gain the fullest picture of what the trout are taking. The contents can then be studied while they are still in the spoon, but it is far better to place them in a shallow, white dish containing a small amount of water which will allow the mass to separate easily and this makes everything much plainer; especially if a photographic record is kept. I photograph any unusual spoonings and sometimes examining them at leisure will yield further valuable information.

 

Sometimes much of the food will be largely digested and all that is visible at a cursory glance is a mass of slime, but nevertheless on closer examination, perhaps in conjunction with a magnifying glass, it is often possible to pick out a few features of recognition. When this is the case the fish may well resume feeding to a different pattern and so a little caution is needed.

 

On occasion a number of live specimens will be seen swimming around the dish: buzzer pupae, daphnia and corixae being typical examples, and examining how they move naturally gives us valuable clues of how we need to retrieve our artificials. Just how so many of these creatures manage to survive in the stomach of the trout, like Jonah in the belly of the big fish, is a mystery – but survive they do!

 

Sometimes a lot of bottom debris will be found mixed amongst the food items and this tells us where the fish have been feeding and consequently where we ought to be fishing our flies.

 

THE DIET OF RESERVOIR TROUT

 

Once you have started to perform autopsies on a regular basis you will begin to gain a much better understanding of what the trout's food looks like as regards size, shape, colour and movement, and as a result it will make you far more choosy in your choice of artificial fly patterns. You will also begin to anticipate at what time of the season and the time of day each of the various creatures can reasonably be expected. Over time you will come to realize that some of the patterns that are generally available are not very suitable and you will probably want to start designing your own flies which incorporate those features that you consider most important. The final and most significant benefit is that, by presenting more appropriate flies to the fish, you will catch a lot more of them!

 

Reservoir trout are very catholic in their choice of diet and they will ingest pretty well anything edible that they come across as they roam the water seeking food. Nevertheless the principle items that fly anglers will need to replicate are:

• Buzzer pupae

• Bloodworm

• Buzzer shucks

• Buzzer emergers & winged adults

• Daphnia

• Damsel larvae

• Water bugs (corixa, shrimps, freshwater louse, snails, aquatic beetles, leeches etc.)

• Sedges (caddis larvae, pupae & winged sedge flies)

• Upwinged flies (nymphs, duns & spinners of olives, mayflies & caenis)

• Fry & small fish

• Terrestrial insects (daddy long legs, beetles, hawthorn flies, drone flies, flying ants, black gnats etc.)

 

I would like to offer one very noteworthy conclusion that I have arrived at from all the autopsies that I have performed over the years and that is, of all the food forms that are around and available to the fish, it is as well to remember that four items probably make up well over 90% of the trout’s diet. Those four items are: buzzer pupae, bloodworm, daphnia and damsel larvae. Any angler who concentrates on these four creatures surely cannot go too far wrong most of the time.

 

So can I persuade you to put your marrow spoon to work next time you are out on the water so you can identify what the fish are taking; and then endeavour to find a suitable representation to copy it from your fly box.

 

Once you start catching fish by using an imitative approach, as opposed to employing random methods, you will find your fishing far more interesting and satisfying, and ultimately far more rewarding into the bargain. I can guarantee it. Tight lines!

 

For further information about autopsies consult the chapter 'Valuable Information Straight from the Fish's Mouth' in my book Successful Reservoir Fly Fishing Techniques.