Finding the Hot Zone in the Run

fly fishing hot zone

The “hot zone” is an expression that refers to the exact spot or stretch in the run where trout will hit your nymph. It’s a common-enough phrase, but I began using it after a wade trip with a guide on the edge of Yellowstone National Park. If you locate the hot zone, you’ve discovered the Holy Grail.

We all know that fish have lies.

They hang in opportunistic or safe places in the river, such as prime lies, feeding lies, and/or sheltering lies. But on a more practical level, many runs, especially the deeper ones, seem to hold large pods of trout. Especially in the spring (rainbows) or fall (browns), fish stack up in some of the deeper pools. Some are spawning, others chase the spawners upriver and feed off the eggs.

Here are several quasi-truths of the so-called hot zone:

1. The hot zone is a narrow window.

Last fall, Steve (my podcast partner) and I fished a river with several deep runs. Near the end of the day, we walked back to a run that Steve had fished earlier in the day. I had not yet fished it. Steve started casting and immediately began catching fish.

It took me a good 15 minutes of casting, even with Steve’s instructions, to begin catching fish. Hitting the hot zone is easier to write about than to do in real time.

2. It’s easy to miss the hot zone entirely.

If you’re fishing a new stretch of river, it’s quite possible that you will miss the hot zone on any given run, especially if you’re moving too fast upriver.

Just a caveat: Too often new fly fishers will camp on one good run and cast for hours in the same place. I’m not advocating that. But if you’re fishing new waters, then patiently working the run is important to cover the possible lies of the fish.

Steve and I have a honey hole on the Lower Madison River that often gets passed by. It’s a ways up the trail into the back country from the access point. The more persistent fly fishers hike upriver, however, and often wade through our honey hole, but they never seem to linger. My guess is that they may catch one brown on the way through but have never had the kinds of afternoons that Steve and I have had.

3. Subtle takes can prevent you from identifying the hot zone.

This is the challenge of all nymph fishing, but reading what is a “take” and what is simply your nymph catching rocks or debris on the bottom of the river is not as easy as ordering black coffee at Starbucks: “I’ll have a grande Pike, please.”

The rule of thumb is to pay close attention to your indicator and then strike at every possible sign. What does it hurt if you strike and nothing is there? Nada. Just let your indicator continue to drift downstream. It’s better to react too often than to wait until you’re certain you have a real take.

4. Fly depth may be the biggest issue when searching for the hot zone.

Whether a smaller creek or bigger river, the depth of the runs change from run to run. So if you’re not adding split shot – or lengthening your indicator – you may not be deep enough.

The bigger issue, though, may be that you are not casting far enough upriver, giving your nymph time to bounce along the bottom in the hot zone. This is especially true in deeper pools. The right depth is key to the hot zone. While the typical solution is to add split shot to your rig, the better solution may be to cast farther upriver (if you can), so the nymph can sink to the perfect depth in the hot zone. The nymph should be at the right depth before it enters the hot zone.

5. After all your persistence and finesse, there may not be a hot zone.

Or there may be one, but the fish are not in the mood. So how do you really know?

If you’ve had one of those days where you’ve caught more than several fish from one run, then you obviously have hit the hot zone. You know it when you hit it. Keep searching!

7 Spots to Cast Your Dry Fly

You’re standing at the river’s edge. The guys or gals at the fly shop have said that the dry fly fishing has been fabulous. So you’ve tied on the size #14 elk hair caddis they recommended. But where should you cast your fly?

If you are new to fly fishing, here are the best spots to cast your dry fly:

Where the trout are rising

This tip is not meant to insult your intelligence.

Rather, it reflects how easy it is to miss rising fish. Sure, the ones that jump halfway out of the water are obvious. But the largest trout often make the smallest ripple. Their snouts barely break the surface.

Spend a minute or two scanning the surface for the subtle rises that are easy to miss.

Where you are about to wade

Fly fishing legend Gary Borger says, “Fish it before you wade it.”

This is good advice. The trout are not always where you think they should be. The best spot might be the water through which you need to wade to get to the next best spot.

Where the drift boats fish

Fly fishers in drift boats do not cast to the middle of the river.

They typically cast to the banks — right where you are standing. If you’re fishing a large river, think of the first eight to ten feet from the bank as a small stream. You probably don’t need to make a twenty-yard cast. You’ve hit the jackpot if you see deeper water along the bank. This is where trout find shelter from predators and easy access to food.

The head of a pool or run

This is where fast moving water (a riffle) rushes into a slower, deeper section of current.

Sometimes, the riffle empties into a pool. I remember an afternoon on the Yellowstone River south of Livingston, Montana where I fished nothing but a riffle. That’s where the rainbows were feeding on blue-winged olives.

In the foam line of a run

Sometimes, the trout are below the riffle in the current itself. These runs can be short or long. Watch for a moving foam and bubbles. This is the food line! I especially rely on the foam line when fishing in slower moving rivers like the East Gallatin in Montana or the Owyhee in eastern Oregon.

The shallow water at the side or the tail end of run

You won’t always find trout in these places, because they offer minimal protection from predators.

But these are great feeding spots for trout when the insect hatches are in full force. Often, the more gentle side of a “seam” (the imaginary dividing line between fast moving current and slow water) is a great place to cast a dry fly. Trout will sip flies there, knowing they can quickly retreat to a riffle if they see the shadow of a bird swooping down on them.

Near a rock

Some rivers – or stretches of rivers — do not have pronounced runs.

Rather, they have a steady flow and depth from one bank to another. If this is the case, look for big rocks. I’ve caught trout in front of, behind, and beside big rocks. Some of these rocks stick above the surface, others do not. One of my favorite stretches on the Gallatin River south of Big Sky, Montana, works like this.

When I find a decent-sized rock, I know I’ll find trout.