Fooling Whom?

AUGUST 2008 — This is a story about a dragonfly. Dragonflies are members of the order Odonate and suborder Anisoptera. Anisoptera means unequal wings and that is true of the dragonfly with two wings on each side of its body of different lengths. The order name, Odonate, comes from the Greek word meaning tooth and teeth they do have, which brings us to this story.

If you strip away the flyfishing mystique of fancy equipment, sage but usually unwanted advice and the blizzard of techniques, you are left with the true art of fly fishing: illusion. Both the practiced magician and the flyrodder foster their illusions with props. The props for fly-fishing are tiny bits of fur and feathers fashioned on a hook with sufficient realism to fool a fish.

On this particular tributary to the Connecticut River wispy clouds of the mayflies were doing their mating dance in the air. Some had reached the end of their life span and were dying on the water, plenty of insects to feed hungry trout creating the perfect stage setting for a flyrodder. Trout were feeding on the surface. As my imitation fly was moving through the air on its way to fool the first fish, a large dragonfly swooped down from above. The dragonfly attacked my artificial fly, snatched it out of the air and tried to fly off with its booty.

Of course in this case its prey was attached to monofilament line that was in turn attached to a fly line that was in turn attached to a fly rod that in turn was attached to me. This dragonfly flew straight on until feeling the tug as it reached the end of the line it changed direction and flew to the end of the line in another direction. It attempted three different straight flight directions and then tried its full repertoire of flight directions up, down, sideways and backward before letting go of the fly. Up until it dropped the fly the dragonfly had been a living miniature kite vibrating at the end of my line.

Dragonflies are insect eaters. Adults are so partial to mosquitoes one of their nicknames is mosquito hawk. They are an ancient insect that dates from 250 million years in the past. There has been little change in their shape but a great reduction in their size over the eons. The largest modern dragonfly measures almost 7 inches wingtip to wingtip but there are fossil remains showing that the wingspan of their ancestors was over 2 1/2 feet. Later I learned this particular dragonfly was likely a black tipped darner (Aeshna tuberculifera) with narrow brilliant blue stripes banding its black 3-inch body.

Water is home to the dragonfly. The female lays her eggs in the water. The egg grows into a nymph that reaches its full size by molting its outer skin as it grows. The nymph‘s usual prey are other insects but they eat anything small or slow enough to be captured including tadpoles and small fish. The nymphs breathe through gills. Depending on the species they spend from two months to two years growing to maturity under the water. Dragonflies achieve their winged adult form with one last molt, this one above the water. The nymph climbs a stick or rock and there split its nymphal case a final time and flies off.

Adult dragonflies are superbly designed to capture food. Their eyes are more complex than other insects allowing them to spot quarry from as far away as 60 feet. Their legs are fringed with spines. The legs are all on the forward part of the body and are held together to form a bristly basket to snare prey from the air. Once captured, they eat small prey in flight. Larger captures are eaten on a branch or other resting place. The adult dragonfly breathes through small openings that feed air directly to the body. Quite an amazing transformation from a crawling water based nymph breathing with gills to a flying air breathing adult.

On this particular day I discovered another dragonfly peculiarity. Dragonflies are stubborn. When they are in hot pursuit of prey dragonfly wings cause a unique clattering buzz so I heard the next attack coming from behind me before I saw the dragonfly. This time the dragonfly came buzzing full speed along the pool chasing the artificial fly on my forward cast. Just as the line straightened out and my fly was about to settle on the water the dragonfly caught it and kept right on going with its prize. When the fly line became taut the dragonfly was yanked to a dead stop and its momentum flipped it upside down, head over tin cups, right into the stream. It struggled unsteadily out of the water and flew away on shaky wings.

This was probably the same dragonfly. Dragonflies are territorial and drive interlopers out of their area. Another little bit of proof was a third attack of my fly. This time it seemed to have learned something from its previous attempts to capture this particular insect. In this attack it flew only fast enough to catch up to and then tap at the artificial fly. After all its troubles with this particular bug it was satisfied to let this one get away. This time the dragonfly flew off never to be seen again by me.

Why did this dragonfly want that artificial fly? Was the magician’s magic that good or did this dragonfly need eye glasses? Despite there being no possible answers to the rhetorical questions, the day was a success since this magician had fooled two of the great insect hunters in nature, a brook trout and a dragonfly.

David L. Deen is River Steward for the Connecticut River Watershed Council, an articulate voice for the Connecticut River for more than half a century.