Quite simply, pools are areas of slower and deeper water (see picture below). This is a very popular type of water, mostly because you can often see fish swimming around. In fact, most novice fly fisherman seem to focus on pools and pass by the other types of water we have discussed in previous sections.
Pools do attract fish for two main reasons:
1. Slower Current - they are able to conserve energy
2. Safety - predators have a harder time getting to them in deeper water
*It is also good to note that pools are especially dense with fish during the winter because they are lethargic and trying to conserve more energy.
Where do fish hang out within a pool?
EVERYWHERE! you can find fish within a pool from head to tail (Head - where the water enters the pool, transitioning from fast to slow and shallow to deep. Tail - the opposite end of the pool where water velocity increases and depth decreases. See picture below). You will find fish close to the bottom, suspended in the water column, or even feeding off the top. On a good day, this is the type of water anglers dream about!
However, it's not all lollipops and rainbows 🍭 🌈 . Because the water is slow, spooking fish is a definite concern. Be sure to keep a low profile and be aware of the waves you create while wading. Nothing is worse than spotting a big brown trout at the tail end of a pool, only to scare him away as soon as you step into the water 😭 .
What is the best way to fish a pool?
First, realize that not all fish behave the same. Some fish are feeding close to the bottom, others are suspended in the water column, and a few are willing to eat off the top. Your goal will be to target each "layer" of fish separately (see image below).
Pools have 3 main parts— Head, Middle, and Tail. Remember, fish can be found in all three sections. Be working the pool from tail to head and shallow to deep, you'll be able to navigate each section and "layer" without spooking other fish.
This is the easiest place to spook fish. Move very slowly and stay low. The transition from deep to shallow is perfect for a dry-dropper rig (see diagram below). This rig allows you to work both fish hanging out near the bottom as well as those willing to snag a dry fly off the top.
This section is slow and deep. Again, we are tying to work all the "layers." With your dry-dropper rig you'll be able to target fish both eating off the top and those suspended in the water column. You may consider lengthening the distance between your dry fly and dropper (this will get the dropper deeper in the water column).
Once you've worked the surface/middle "layer," try going a little deeper. This is best accomplished with a standard nymph (see diagram below) or euronymphing rig. Keep adding weight, tying on heavier flies, and/or adjusting the distance between the indicator/flies until you reach the bottom.
Because food first becomes accessible at the head, this is usually where the dominant (larger) fish are found. The same shallow to deep principle still applies, but reaching the bottom "layer" is a bit more technical because of the ledge created by a change in water depth/speed (refer back to to diagram above).
Experiment with where your flies enter the water as well as weight/fly size. The ideal cast will allow your flies to naturally follow the drop in depth. Too heavy will cause it to get caught up above the ledge, too light and they will zoom right over the fish's head.
Strategically working a pool from tail to head and shallow to deep is sure to bring you some success 🏆 . Our next water type section will cover Glides.