Salmonfly is a 30-pounder meal for a trout

R

emember David Letterman’s comedy sketch when he called in his burger order at McDonald’s?

“Gimme a quarter-pounder, a half-pounder, a three-quarter pounder and … a pounder!”

To a hungry trout scrounging for tiny insects, a salmonfly is a 30-pounder!

Adult salmonflies, sometimes referred to as the “State Bird of Montana,” can reach a length of over 2½ inches, providing a major source of protein for fish.

The salmonfly hatch is an annual late-spring, eagerly-awaited event for anglers.

In Northwest Montana, the salmonfly hatch generally appears in early May on the Thompson River. 

Salmonflies have been reported on the Flathead Middle Fork as high as Bear Creek in early summer.

Triggered by water temperature, hatches work their way upstream.

Fly fishers dream of a big trout exploding the surface, slashing at their huge black/orange foam or deer hair fly.

Newbies are too often obsessed with fishing the front end of the hatch, while fishing 4-7 days behind the front allows fish time to digest their first gorging.

Near dawn, during the hatch, large black Pternonarcys california nymphs crawl from the streambed onto streamside vegetation where they emerge as adults and search for mates.

About midday, they take flight, the females dipping to the water to drop eggs. That’s one time when an opportune trout takes a 30-pounder.

It’s not uncommon, at this time, to catch trout with several flies in its mouth, not yet swallowed!

The eggs settle onto the streambed to develop, then grow into nymphs emerging in three years.

Aquatic Ecologist Dave Stagliano, reported drought affects salmonflies by raising water temperatures, dewatering (less habitat) and siltation of streambed (lack of flushing action).

So, basically, three years of decent streamflow are required for a good salmonfly hatch.

Go to:  http://fwp.mt.gov/mtoutdoors/HTML/articles/2011/Salmonflies.htm.

Adult salmonflies often fall or are blown off streamside vegetation, so floating your Bird’s Stoneflies and Dernan’s WaterWalkers close to shore is a good bet.

Fishing a salmonfly hatch can be the fly fishing highlight of the year.

Don’t miss it!