As I started home a few days ago, along a concrete walkway adjacent to some tall grass, I couldn’t help but notice the numerous grasshoppers rising from the edge of the sidewalk. They leapt or fluttered waist-high into the air, covered a dozen feet to a new patch of grass farther from my big tromping feet, and disappeared once more into the tangle of weeds and wildflowers.
My first thought was that grasshopper wings don’t look meant for flying. They are awkward — almost prehistoric. Their wings seem merely to slow the descent of the falling insect after a big jump rather than really enabling the creatures to soar. No wonder they spend their lives on the ground hiding in the grass.
My second thought was I needed to get out on the river and cast some imitation grasshoppers.
It was the last day of August. Late summer is a wonderful time to fish terrestrials instead of aquatic insects. Terrestrials are insects like ants, grasshoppers, bees and beetles, that in theory are supposed to spend their lives over dry land. But ants living in the sand of a stream bank or walking along the branches of a tree over the water, are prone to falling in from time to time. And when you see how clumsy a grasshopper is in flight, it’s not surprising that on a breezy day some of them blow into the river. Summer of 2017 also saw a hatch of 17-year cicadas emerging in Vermont. My wife has been spotting their husks on the sides of trees. A cicada blowing into a stream makes a wonderful meal for a hungry fish. On years of major hatches in the Appalachians, they can provide a source of food and energy for a whole host of creatures from fish to birds to bears.
In terms of numbers of insects, the majority of a trout’s invertebrate diet are aquatic insects like midges, mayflies, stoneflies and caddis flies: insects that hatch under water and spend most of their lives crawling, burrowing or swimming along the stream bottom, before swimming to the surface and emerging as flying adult insects. Since they live in the water, it’s not surprising that there are far more of these available to a trout for food. But though numbers favor the aquatic invertebrates, the terrestrials tend to have a much greater mass, and therefore provide a much greater caloric and nutritional “meal.” Think about the difference between a big juicy grasshopper and a mosquito. (Having swallowed more than one mosquito while biking or fishing, I don’t have to do much imagining.) While less than a tenth of the insects eaten by a trout may be terrestrial, up to half of the consumed mass can be.
So there I was on Saturday starting up a favorite local stream with a favorite grasshopper pattern tied to the end of my tippet. In the first spot I stopped to fish, I drifted the fly down the center of a riffling current. As it passed over a shelf and into slightly deeper water, a large splash on the surface signaled the strike of what was presumably a large fish. I say this all with uncertainty, however, because the fish somehow missed the fly. Perhaps the drag of the current on my line pulled the fly out of the fish’s mouth a fraction of a second too soon. I’ll never know.
That was the only strike I got in two hours of fishing. Some time later, coming around a bend, I spotted another angler 75 or so yards upriver. Disappointed not to have the place to myself, I stopped fishing and considered my options. Trying to skirt around the other angler, especially if she were also moving upriver, would be very rude. When anglers behave that way, the entire community around a local river will deteriorate quickly. That wasn’t an option for me. A second choice was to turn around and leave, but I knew that if I left this water, by the time I walked back to my car I wouldn’t have time to drive elsewhere and fish any more that day.
So I waited. After a few minutes, the other angler continued on upstream and disappeared. Though my expectations of catching fish always drop if I am following another angler along a small river, that option was better than quitting altogether (which would lower my expectation of catching a fish to zero). So for the next hour I continued upstream, fishing slowly, and pausing whenever I came around a corner and saw the other angler ahead of me until she disappeared again.
The pausing and waiting gave me an opportunity to spend more time observing and enjoying the stream itself, without the busy-ness of waiving my fly rod around. Though an occasional mayfly and caddisfly floated past, I became even more aware first of the tremendous number of small midges hovering just over the surface of the water. Then I began to watch the antics of a couple dragonflies hovering right in the middle of the midges and feeding voraciously upon them, darting left and right, up and down, forward and backward. I became aware that if I kept my eye on a particular little midge in the vicinity of the dragonfly, I could often watch the dragonfly catch the very insect I was watching.
I saw next the husk of a large black stonefly sitting on a streamside rock, where the stonefly had crawled out of the water, shed its nymph skin, and flown off as an adult. A dozen yards upriver, I came upon what I thought was another husk of a large black stonefly, but when I bent to look more closely it started to crawl. It was already a winged adult, but seemed still to be waiting for its newly hatched wings to dry before taking flight.
While a midge, mayfly or mosquito may pale in comparison to a big juicy grasshopper as a mouthful for a trout, a big black stonefly is in a different category of aquatic insects. No trout can pass one up. So I gave up fishing dry fly imitations of hoppers and switched to a large stonefly nymph. I drift the fly through a beautiful run where swift current dropped into a pool beneath the shade of an overhanging tree.
And I continued not to catch any trout.