Belly | Mending Fly Lines | Presentations Tips

If Whitey doesn't take action, his belly will get bigger and bigger.

It’s time for part 2 in our series about mending your fly line. Today it’s all about ‘belly’!

Fly Line ‘Belly’ and Mending

We have talked about the word ‘mend’ and its meaning. So now that we know that the mend will affect the presentation of the fly, let’s talk about ‘belly’.

Belly can be explained as a downstream arc in the fly line as it floats in the current. Belly can be good or bad, depending on the situation. Think of the fly line as a sail, and the water as the wind. Wind fills the sail and pushes the boat; water fills the belly and pulls the fly.

Belly is Bad

You might have noticed when there is belly, in fast water, the current fills the belly until it becomes tight and then begins to pull the upstream portion of the fly line – often dragging the fly out of the zone or streaking it across the surface. If you are nymphing, the fly will not be able to sink enough to give a good presentation. If you are dry fly fishing, the fly will have minimal time to present itself.

In this situation the belly is bad. The fly line must be mended upstream to remove the belly, allowing more time for natural fly presentation. Sometimes the current is so fast that continuous mending is required to allow the fly to drift properly.

Belly is Good

When is belly good? When you need to move your fly, to speed it up, swim it faster or skitter it cross the surface. This is often the case when the current is slow, or at the end of the swing or drift.

Here’s one example. You’re swinging a streamer. It’s halfway through the swing and the current starts to slow. The line stops swinging so the fly stops swimming and begins to sink to the bottom. There is still a lot of water left to fish but not enough current to move the fly. This is where you want to have belly to pull the fly through the last half of the swing.

During your swing, as the fly line begins to slow, mend a downstream belly into the fly line, allowing more water to fill the belly, thus pulling the fly and continuing the swing. This will also work to skitter a dry fly across the surface.