Trout Rise Forms: What are they and Why they Matter?
Updated: Oct 19, 2021
A trout's rise form describes the behavior of a trout's body when it is eating prey on or in the surface film. There are three primary types of rise forms: Splashy rises, bulging rises, and surface rises.
I’m so entranced by the sight of rising trout that I could probably stand in the middle of a stream and watch them without making a single cast. I use the word probably because the only time I stand in the middle of a spring creek is to cast to trout, and I’m not planning to change that any time soon.
Reading rise forms can help identify:
Where the trout is holding
What stage of the insect’s life it's keying in on
Sometimes, what type of insect it’s feeding on
*A common mistake is assuming the fish are eating the same flies observed in the air and on the water. This is great for determining what’s hatching, but rise forms are the trout’s way of telling us what they're eating at a specific time and which patterns and techniques might be most successful.
All rise forms are fun to watch, and a little attentiveness and background knowledge can increase the odds of hooking up with them.
What is a splashy rise?
Splashy rises are often heard as much as they are seen. You may have had your attention focused on changing flies, tying on tippet, or looking up at the beauty around you, and been “interrupted” by the sound of a trout ripping through the surface film. This would be considered a splashy rise. These occur when a trout is chasing and attacking its prey instead of holding in a current lane and waiting for the insects to come to them.
What does a splashy rise look like?
It occurs any time more than just the trout's snout, and/or back fin breaks the surface, and is accompanied by water splashing around the rise ring. The impact on the water’s surface with a splashy rise looks similar to throwing a small pebble into the stream.
What does a splashy rise tell us?
This rise form typically signifies opportunistic instead of selective feeding. When no abundance of food is floating down the current’s "conveyor belt", trout aren’t keyed in on anything specific and are open to taking a variety of insects. When they aren’t keyed in on anything specific, they have no reason to hang out in the top of the water column, so they hold closer to the bottom. A commonly held belief is that splashy rises signify trout feeding on emergers or caddis flies. While this is sometimes true, it’s not what they’re eating that causes the splashy rise, it's that they have to shoot themselves through the fast moving water before their target gets away.
Key strategies for splashy rises:
Use an attractor fly a little larger and brighter than you typically would. The fish is holding closer to the bottom and you need to get its attention. Now’s not the time for tiny midge patterns.
Get the fish excited. It takes a lot of energy for a trout to shoot up through the water column, so they need to believe it’s worth their time. One way to induce excitement is to add a little movement to the presentation.
Best flies for splashy rises:
Terrestrials such as hoppers or ant patterns
What is a bulging rise?
Physics tells us that anytime a trout moves, water is pushed away from them in the opposite direction. Regardless of the rise form, if a trout moves vertically while close enough to the surface, water is pushed up and creates visible waves. What makes bulging rises different, is that the fish itself never breaks the surface. The visible disturbance is created from water being pushed away from the fish instead of by the fish itself.
What does a bulging rise look like?
No fins snouts or bubbles will be seen, just a bulge from which the waves move away from. It’s also possible to see the flash of the fish’s side or open mouth as it turns back down after capturing its prey.
What does a bulging rise tell us?
This rise form has caused hair pulling frustrations for many. Fly fishermen see what APPEARS to be trout feeding on the surface, and immediately tie on an adult imitation. Bugling rises however signify fish feeding BELOW the surface, not on or in it. It also indicates that the fish are holding somewhere closer to the middle of the water column. They’re off the bottom enough to get a good look at their meal, but not taking the risk of holding too close to the top.
Key strategies for bulging rises:
Use a dry dropper rig with the dropper attached 4-6 inches below your dry. The dry should be no more than 1-2 sizes larger than the dropper.
Trout see underwater much better than they do above the surface, so be subtle with the choice of dropper pattern and attach it to the dry with fluorocarbon tippet instead of monofilament.
Stay low and move slow. When fish are in the middle of the water column, their field of vision above the water is much greater than when they hold closer to the surface.
Best dropper flies for bulging rises:
RS-2 squeezed wet
Pheasant tail nymph
What is a surface rise?
It’s the happy medium between a splashy rise and bulging rise. The fish breaks the surface, but not fast or strong enough to spray water. Surface rises come in many different forms, but the one constant is that the trout’s nose breaks through the film.
What does a surface rise look like?
Look for snouts breaking the surface film without much more of the fish’s body coming out of the water. Also, because trout bite down when they eat instead of opening their gills and “sucking” in their food, they create air bubbles that are usually visible after the snout has disappeared back into the water.
What does a surface rise tell us?
This rise form typically signifies selective feeding. When there’s an abundance of a certain insect riding down the current conveyor belt, trout become so focused on them that smooth talking them into taking anything else can be tough. The bright side is, this also means they are hanging out closer to the surface, causing their range of vision to decrease. One frustrating aspect of fishing this type of rise, is that if there are multiple insects on the water, it can be difficult to determine which bug and which stage of emergence the fish are keyed in on. The best way to figure this out is through trial and error.
Key strategies for surface rises:
Just because you see bugs in the air and on the water, don't assume those are what the fish are keyed in on.
Change patterns early and often until you find our what they are keyed in on.
Because they're holding so close to the surface, they have limited visibility. This means two things:
Accurate casts are critical. In order to compete with the naturals on the water, the fly must enter the trout's window.
Because of the fish's limited vision above the surface, by moving low and slow it's often possible to get much closer to them than you typically could.
Best flies for surface rises:
Elk haired caddis
With a little observation of the trout's rise form, we can get a clearer picture of what they’re eating and which pattern to try first. However, dry fly fishing is as much an art as it is a science. Every day, fish, and stream is different. If they were all the same, it would be too easy and lose much of its excitement!