Trout Fishing Tips | How to Read Rise Forms

Originally posted on Fishing on SI | By Jasper Taback | Last updated May 30, 2025 8:00 AM ET

Catching a trout during an insect hatch feels like a little pat on the back from the fly fishing gods. Among all of the natural insects available, a fish decided to take your imitation. Quite a few things had to go right for it to happen – sometimes it all comes together by dumb luck, but more often, it’s a result of careful observation.

Step 1: Figure Out Where

Before you worry about what the fish are eating, focus on where they're eating. Just because a trout rises doesn’t mean that it’s necessarily eating insects on the surface. Often, trout will snack on emergers – insects stuck in the surface film, struggling to break through.

Surface Eats vs. Emerger Eats

Differentiating between surface and emerger eats is fairly straightforward, and it has to do with bubbles. A tell-tale sign of an emerger eat is a rise that leaves no bubbles. When trout eat emergers, much of the commotion happens under the surface, resulting in subtle rise forms. When a trout eats on the surface, it’s a quick movement that breaks the surface film and creates air pockets that you can see.

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Step 2: Figure Out What

Some anglers I’ve fished with say that they can tell a caddis eat from a mayfly eat – maybe they can, but most people can’t. In my experience, rise forms tell you much more about the where than the what.

Finding a passable imitation of a trout’s desired insect comes from a combination of observation and trial and error. First, take a look at the bugs floating on the water’s surface. If possible, pick one up, go through your fly box, and select a fly that roughly matches the body shape, size, and color.

Trial and Error

The insect that you found floating on the water might be the ticket, but it might not. Rarely is there only one type of insect hatching at a given time, and the fish might be keyed in on something else. That’s where trial and error come in. –

When your first fly doesn’t do the trick, do some more watching. If you see another insect drift by that looks different, try a fly pattern that matches that one. You might have to repeat this process a few times – with patience and repetition, you’ll likely land on one that the fish are willing to eat.

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Stop and Look

When trout are rising all around you, the last thing you’re going to want to do is put your rod down and watch. Do it anyway.

Give two anglers an hour to fish a hatch, and I’d bet the one who spends the first ten minutes watching outfishes the one who starts casting right away. Take a breath, look around, and let the trout show you what to tie on.