Think Like a Trout, Act Like a Bug.

Monday, June 14, 2021

Migrating Damselfly Nymphs

The month of June is prime time for fishing damselfly hatches on lakes. Although I have witnessed trout specifically targeting the adults as they perch on overhanging bushes along the shoreline, it is a rare event. During a hatch, most of a trout’s attention is focused on the migrating nymphs as they make their way from submerged weedy shoals to emergence sites along the lake-shore.  

Depending on conditions, and the damselfly species involved, migrations can take place along the bottom or just under the surface. I have only encountered a handful of hatches where I observed nymphs migrating just sub-surface. Most of the time, the nymphs are swimming along the bottom or just above the weed-tops. If I see signs of recent emergence, or an active hatch in progress, I will work a Migrating Damselfly Nymph on a sink-tip line with a slow or intermediate sink rate. In either case, the mode of propulsion for the nymph is the typical and somewhat inefficient side-to-side undulation of the body.

A multi-exposure strobe photo of a swimming
damselfly nymph (Enallagma annexum)

Creating a fly that effectively mimics this undulating behavior has been the goal of many a fly tier over the years. Strategies have included everything from long tails of marabou to articulating bodies, and even the addition of a tiny crank-bait style lip to the fly – but all to no avail. While some of these fly patterns do provide a small measure of undulatory action (in the up and down dimension as opposed to the desired side-to-side direction), I feel the advantages are not sufficient to warrant the extra effort. Instead, I focus on the more important factors of retrieve rate and search image.

A newly emerged (teneral) damselfly with shed exuvia (Lestes sp.) - a sure sign
of a hatch in progress.

If threatened, damselfly nymphs can move at a pretty good clip – but only for short bursts. During migration, they typically plod along in a very slow but determined manner, often pausing for short periods to rest. Your retrieve should follow this pattern. A very, very slow hand-twist retrieve (¼” to ½” per second) with the occasional pause will bring more takes than a rushed retrieve. It takes a lot of patience to work a fly this slowly, and you will need to use a line with a slow enough sink rate to avoid constant hang-ups, but the higher percentage of takes makes it worthwhile.

Search image requirements are fairly simple. There is the usual size, shape, and color to consider. Beyond that, I like a fly with prominent eyes and just a short tuft of marabou to imitate the broad set of gills at the posterior end. A medium olive Migrating Damselfly Nymph in size 10 gets the job done under most circumstances.


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