Understanding Rise Rings

When a trout feeds on or near the surface, it creates a ring in the water that can appear as a violent splash or a mere dimple. Recognizing certain characteristics of this rise ring can tell you a lot about where the fish is positioned, where his feeding lane is, his size and possibly what he’s feeding on.

Lengthy chapters of vast and detailed information on this topic can be found in a number of well known fly fishing books. I recommend reading them. This article will attempt to condense that information into a useful overview. As always, these are general rules to which there are always exceptions!

Rise Ring
Dimple Rise

Common or Simple Rise

A common rise is characterized by a quick view of the trout’s head, dorsal fin, and often “wagging” tail, followed by a boil of water. It indicates that the trout is positioned near the surface and feeding on insects on the surface or near the surface film. The insects are probably medium to large in size. Because of the increased exposure to predators, trout rarely position themselves near the surface unless there is a lot of food available. So, if you see this kind of rise, keep watching. Chances are you will see the same fish repeatedly feeding.

Surface Swirl

The surface swirl is similar to the common rise but without the appearance of the head, fin or tail. You only see the water boil. In this case, the fish is probably positioned within a foot or two of the surface and is feeding on insects at least two inches below the surface. You can spend hours casting dry flies to these kind of rises without a take, but an unweighted nymph or wet fly fished just below the surface can be deadly.

Poking or Dimple Rise

As the name implies, this rise form appears as just a dimple on the surface and if you look carefully, you can often see just the nose of the trout penetrate the surface. This rise form also suggests the trout is positioned near the surface but likely feeding on small insects on or just below the surface. This type of rise is most often seen in slower pools and runs, slow edges of currents and eddies.

Splashy Rise

When a rise ring is more of a splash, it can mean a few things. Usually, it just indicates that the trout is positioned deeper in the water. By traveling farther up the column for food, the trout’s momentum often results in more of a splash on the surface. If the trout is positioned deeper, this was likely an opportunistic rise from a fish not necessarily focused on the surface. You may never see him come up again.

Similarly, trout feeding on insects that emerge and get off the water quickly can display a splashier rise. Caddis flies fit this description, so many anglers assume (sometimes incorrectly) that a splashy rise means trout are feeding on caddis. And sometimes a splashy rise can simply be the result of a smaller, eager trout rising recklessly.

Gulping Rise

A gulping rise is like a greatly exaggerated common rise. The trout’s mouth is wide open and his entire backside breaks the surface, followed by an often audible “gulp.” You’re likely to see this type of rise during very heavy hatches when there are frequently multiple bugs very close together on the surface. The trout may eat as many as six bugs in one rise. If you’re seeing this, you’re at the right place at the right time. Try to match what you see on the water and don’t get your leader in a big tangle!

Jumping Rise

A jumping rise is when the trout completely clears the water, sometimes by a few feet! This could mean the fish is feeding on bugs in the air just above the surface, or possibly something large like a mouse or even baitfish. In any case, a jumping rise suggests a brief moment of opportunity and not a steadily feeding trout. I don’t recall ever standing in a pool and seeing dozens of trout routinely jumping out of the water. Most experienced anglers recognize the jumping rise as fool’s gold, shake their heads and move on.

Where is the trout?

As mentioned above, certain types of rise rings can suggest how deep the trout may be. However, there are other things to consider when determining where in the stream that trout is positioned.

Trout Rise
Trout Position vs. Rise Location – Illustration by Jason Borger

First and foremost, when a trout rises in a stream, he is going to drift back during the process, then return to his original position. So the trout is actually positioned upstream of where you saw him rise. If he is holding near the surface, his position may only be a few inches upstream of the rise. If he’s holding in deeper water, his position may be several feet upstream of the rise.

When a trout rises, you’re also going to see a “push” of water, like a little wave. That wave usually pushes upstream. But if the wave pushes to one side or another, it indicates that the trout came over to feed. So, he may be holding in one lane and feeding in another.

There’s a lot to this, I know. The best advice I can offer is when you see a trout rise, don’t immediately cast a dry fly to that spot. Think about what the rise looked like and stop and look for others. Identifying rise rings may not give you all the answers, but it will give you a great place to start!

A Matter of Degrees – Water Temperature

Understanding Water Temperature

Checking Water Temperature
Checking water temperture

One of the most significant factors that determines how, when, or even IF a trout feeds, is water temperature – at least with wild trout. Stocked trout are raised in hatcheries and fed every day, so they are used to eating every day. Water temperature can impact the way they feed but not nearly to the extent it does a wild trout.

Cold Weather Fishing
A cold weather stocker

An ideal water temperature for a trout is in the upper 50’s to low 60’s. If you show up at the river, dunk your thermometer in the water, and get a reading of 60-degrees, chances are you’re going to have a pretty good day – assuming you do everything else right. On the other hand, if you do everything exactly right but the water temperature is 38-degrees, you may not even get a strike.

On a broader scale, I think of anything between 50 and 68-degrees to be reasonable. But there are variables. 52-degrees and falling due to a cold front may result in tough fishing. 48-degrees and rising due to a warm front may produce excellent fishing. Fish will probably be sluggish if it’s 68-degrees and rising in a summer drought. But 68-degrees and falling because of a summer rain may really turn them on.

With warmer temperatures, it’s more about the oxygen than anything. Trout need oxygenated water and typically, the warmer the water, the less oxygen. If water temperatures hit 75-degrees for more than a few days in a row, trout can’t survive. They’ll either search out more suitable conditions or die.

Stream Thermometers
A stream thermometer can be a valuable tool when searching for active trout

With excessively cold water, it’s more about metabolism. As a survival mechanism, their metabolism changes when water temperatures get extremely cold and they don’t require as much food. It’s similar to a bear during hibernation. So if you’ve ever tried to get me to take you fishing in the Smokies in January and I talked you out of it, that’s why. I have great gear and am not afraid of getting out in the cold, but the fish just wouldn’t be feeding.

On some extremely fertile rivers, this may not be the case. There may be enough food through the winter to keep the fish feeding. I know I’ve fished some excellent winter hatches in Montana. But the streams of the Smokies are the opposite of fertile. They’re some of the oldest mountains in the world and consequently very acidic and nutrient poor, which means there is just not a lot of food, especially in the winter.

There are a number of things that can influence water temperature, with air temperature being one of the most obvious. In the mountains, air temperature and consequently, water temperature can vary significantly by elevation. For instance, a river at 2000’ elevation may see an air temperature of 85-degrees in July with a water temperature of 68-degrees. But if you go to a stream at 3800’ elevation on that same July day, you may find an air temperature of 75-degrees and a water temperature of 61-degrees. That’s why I typically like to focus on high elevation streams in the middle of the summer.

Of course, the opposite is true early in the season. The high elevation streams may be too cold while the low elevation streams are starting to turn on. I once guided a local gentleman on a high elevation stream in July and we had a very productive day. He called me, frustrated, the following March. He said he’d just been to the same stream I took him to, did everything the same way, but didn’t even get a strike. In July, the water temperature had been 60-degrees on that stream. When he went back in early March, it had been closer to 40-degrees. It matters.

Tree canopy can also have a big impact on water temperature. A bigger, more open river may not be very productive on a late June afternoon. But a smaller, more heavily canopied stream at the exact same elevation might be very productive. It seems pretty obvious when you think about it, but the more direct sunlight that reaches a stream, the warmer the water is going to get.

Time of day is another big factor. A lot of people think you have to be on the water at the crack of dawn to catch fish. This is only sometimes true when you’re talking about stream trout. In the heat of the summer, very early and very late in the day are probably the times when you’ll find the most active fish, because you’re getting slightly cooler water temperatures. However, if you’re fishing in early March or late November, you’ll likely find more active fish in the middle of the day, when water temperatures are slightly warmer. That’s one of the reasons why our peak fishing seasons are in months like May or October. The temperatures are mild pretty much all day, and the fish are active pretty much all day.

This is all very specific to free flowing streams. Tailwaters are totally different animals all together. When a river is dammed to form a lake, they release water from the dam every day to control flooding and to generate electricity. The river that is formed below the dam from these releases is referred to as a tailwater.

Norris Dam
Many rivers below large dams maintain nearly constant water temperature all year

The water that they pull from the lake to form the tailwater comes from near the bottom of the lake. Because that water is so deep, it receives no sunlight and is basically insulated by all the water above it. So, the water that comes out of the dam is approximately 50-degrees, regardless of time of day, time of year, or air temperature. That’s why that big, wide-open river can support trout. Spring Creeks are very similar because the water source is deep underground, insulated by earth.

How deep the lake is determines how much cold water “storage” it has. That and the volume and frequency of water releases determine how far down river the water stays cold. Your typical East Tennessee tailwater will maintain these temperatures, and support trout, for about 25 miles. So when it comes to tailwaters, you’re always going to have about the same water temperature, making them year round fisheries. With tailwaters, it’s mostly the timing and duration of the water releases that determine when, or even if you can go and how much success you’ll have.

Back to the mountains, water temperature is one of the things that I pay the most attention to when deciding when and where to fish. I’ve been doing this a long time so I just kind of know based on all of the conditions. Until you “just know,” a stream thermometer can be one the most valuable pieces of gear in your bag.