Controlling Depth

Posted on May 04, 192001 at 10:50:03:

Opening day found me waist deep in 35 degree water battling sleet, frozen guides, fingers, and toes. As I struggled to make my fingers tie on an olive bead head Woolly Bugger I could hear snowmobiles cruising the trails adjacent to the river. What a combination, I thought to myself, snowmobiles and fly rods! Just as I was contemplating whether or not to seek help for my obvious fishing obsession, the weighted Woolly Bugger hit the water with the grace of a sparsely feathered brick. No time to worry about finesse in such extreme conditions. Strip, pause, strip, pause,.wham fish on! The L. L. salmon seemed as eager to grab my offering as I was to battle it and set it free. That scenario would repeat itself many times that day allowing me to forget about the cold. Sometimes everything is just right. That day was one of them.

When we plunge into the water to catch fish there are usually two big questions on our mind. Where are the fish and what are they taking ? I would like you to add two more questions to your list. How deep are the fish and how do I get down to them? By considering these two additional factors every time you fish you will most certainly have more days when everything is just right.

How deep are the fish?

Within a moving body of water fish may be at a variety of depths at any given time of the day. Many people think that they can put away the high density sinking gear when the hatch months are on in May, June, and July. Keep it out. Fish are not always suspended high in the water column even during heavy hatch months. It may become necessary to go deep during these times of the year. Be flexible.

Fish can provide clues to the depths at which they are feeding. Obviously rises, swirls, gulps, and dimples are a good indicator that the fish are suspended and actively feeding at or near the surface. But what about the majority of the season when this is not the case? It then becomes necessary to search a bit harder.

A most important piece of fish finding gear is a good pair of polarized glasses. These glasses will allow you to cut through the glare on the water to see structure, fish, and your fly. With time you will become accustomed to spotting fish or subsurface feeding activity. Often I can see the subtle light color when a fish opens its mouth or the white flashes as fish turn sideways to scrape insects and other invertebrates off the bottom. None of these important clues would be detected without my glasses.

The best indicator that fish are deep is when you do not see any sign of fish feeding activity at all despite all honest attempts of spotting such activity. You can bet that they are feeding.

How do I get down to them?

Traditional fly gear is buoyant. No question about it. The large diameter flyline and the fly with its low mass to volume ratio (density) is constantly working to defy gravity. Leaders exist to connect the two and are also somewhat buoyant. I have an experiment for you to try. Take your full floating line, a 9ft leader, and your heaviest weighted nymph and head to the local stream. Cast the nymph directly upstream and allow it to drift straight back to you as you observe the depth that it is at when it passes.

Now understand the following:

a) The fly sinks with time. The fish that you present to are not at your feet. This means that the fly will be even closer to the surface when it is drifting over the fish because it has not had as much time to sink as it did in your experiment .
b) Faster current decreases the amount of drift time. If the current is faster your fly runs shallower.
c) Anytime there is line drag your fly will run shallower. In your experiment you cast your fly directly upstream to virtually eliminate this drag. How often can you actually do this while fishing ?

What can we conclude from this experiment? When using traditional fly gear on moving water it is very difficult to get the fly down to where you may want it! In most cases you may think your down deep but you are truly not. Here are some suggestions to run deep.

a) Use flies that are heavy such as weighted flies or flies with brass or tungsten bead heads.
b) Be sure that flies are tied with materials that absorb water.
c) Utilize sinking leaders. If using a sinking leader with a standard monofilament tippet, keep the tippet as short and fine in diameter as possible.
d) Use full sinking or sinking tip lines.
e) The greater the diameter of the monofilament used in your leader the more difficult it is for the fly to pull it down. Use the finest possible diameter of mono.
f) Eliminate drag from your presentations. Utilize full upstream casts when possible.
g) If your target is deep, cast far beyond it to give the fly the time to get down.

These guidelines will help you to catch all of those fish that your friends say, �are not feeding.� Experiment, observe, learn, but most of all, have fun! Don�t catch them all.

Gary Scavette is a licensed captain , registered Maine guide and the founder of Northeast Anglers Inc. He welcomes any questions or comments related to this column or fishing in general. He may be reached at 1-800-558-7658 or by e mail at

Return To Northeast Anglers' Articles and Stories

Post-It © 1997, All Rights Reserved.
DBasics Software Company P.O. Box 6034, Alliance, OH. 44601