FishbugsThe Aquatic Insects of an Eastern Fly Fisher

Text and Photographs by Thomas Ames Jr.

Fishbugs

FishbugsThe Aquatic Insects of an Eastern Fly Fisher

Text and Photographs by Thomas Ames Jr.

27Spring does not come all at once to northern NewEngland. It is cruel that way, a lover who teases,offering hope and warmth one day, only to turndistant, harsh and cold on the next.

The first sign that the icy grip of winter isbreaking is the arrival of the winter stoneflies.Thetiny Capniidae appear on the windows of my stu-dio in late February. Some are wingless and have tocrawl up the thirty feet of brick that separates mywindows from the river below.The snows arereceding, the days are warmer, and the sugar housesare busy making syrup, but it is still winter. Moresnow will fall, and an icy blast can come downfrom the north at any time.There will be at leastone more good nor’easter in the forecast.

True spring arrives on a fragrant breeze whenfields and forests come alive and fill the air withtheir scent. It can arrive at any time of day. I mightnotice it when I let the dog out in the morning,during a midday errand, or while driving home inthe evening.Within days, the tips of crocuses anddaffodils are pushing their way up through the soft-ening soil.The songbirds return on the same windand fill the mornings with their chatter.

The trout waters respond more slowly. Even as the warmth of the April sun penetrates thedepths of the rivers it fills them with the icy runoffof melting snows. Lakes and ponds stay cold undertheir frozen caps. I wait on the banks of theOttaquechee for the Quill Gordons and watch forthe first rise of spring.

Spring

28 For generations, seasoned members of the fishingfraternity on both sides of the Mississippi knew thefirst spring olives as Baetis vagans. In 1987 the aca-demics took a close look at the morphologicalrelationships within the family of swimmingmayflies known as the Baetidae and re-sorted thespecies list. Vagans turned out to be the samespecies as B. tricaudatus, and the latter name, anapparent reference to the larva’s three tails, pre-vailed. Some of the early season Baetis nymphs thatappear in my seine net are two-tailed, and I assumethese to be the distinct species known as B. bicauda-tus. In both species the middle tail of the adults isimperceptible.As far as fishing is concerned, it’s onebug, and it’s a Blue-winged olive.The old timerswill go to their graves with vagans on their lips.

The little olives are the harbingers of the dryfly season. Compared to the miniscule caddis andmidges that hatch in the late winter, and to the tinyolives that close out the fall season, tricaudatus dunsare giants at seven or eight millimeters, the equiva-lent of a size eighteen hook.They are also notori-ous for hatching in lousy weather.

It is common to confuse the spring olives withthe true BWO’s that appear in the summer.Although they are roughly the same size as B. tri-caudatus, the summer olives are of a different family,Ephemerellidae, whose adults have three tails andmore fully developed hind wings.The misnomerwas imported with the English patterns. Halfordand his compatriots used the term exclusively fortheir three-tailed Ephemerella ignita, and referred to their Baetid flies as "olives," "iron blues"or "pale wateries." Their pattern, however, conve-niently matches our small, domestic, two-tailed,slate-winged, olive-bodied mayflies, and so thename has stuck.The use of the term "rusty spin-ner" to describe the final adult stage is common toboth continents.

In the middle of the twentieth century,American fly fishers began to acknowledge theimportance of imitating the larval stage as well asthe hatching duns.They discovered that Baetidnymphs were one of the largest components of thedaily downstream migration known as behavioraldrift, and they welcomed a new pattern that hadmade its way across the Atlantic, the Pheasant TailNymph. Frank Sawyer, an English river keeper,designed it without any suggestion of legs, to imi-tate a nymph in the act of swimming. Sawyer’s pat-tern and its American descendant, the TrothPheasant Tail, have endured as classics that are stillfound in almost every fly box, including my own.

The Little OliveBaetis tricaudatus, family Baetidae, order Ephemeroptera

Sawyer’s Pheasant Tail Nymph

Baetis tricaudatus larva

32 The mayfly that has inherited the title of QuillGordon is a staple of the earliest writings onAmerican fly-fishing entomology. It is one of sever-al species, including Iron fraudator, that the ancestralauthors described in detail but which have sincebeen determined to be synonymous. Most regardedits emergence as the first important event of spring.They waited eagerly for the water temperature toreach the magic threshold of 50˚F, when the hatch,and the season, would begin.

How pleuralis got its nickname is open tointerpretation. Preston Jennings coupled the insectwith the pattern in his Book of Trout Flies, but healso recommended the Quill Gordon to imitateRithrogena impersonata, a much darker insect of thesame family, Heptageniidae.

The nymph is of the type known as "clingers"that live in very fast water. It is a marvel of hydro-dynamic engineering.An Epeorus larva is utterlyflat, with eyes set on top of its head like a flatfish.Large, overlapping, plate-like gills extend along itssides to harness the force of the current by pressing

the insect onto any surface it cares to traverse usingits strong legs and claws. But because these gills aredesigned for fast, cool water, they aren’t very effi-cient, putting Epeorus at risk in any habitat wherethe oxygen has been depleted, either by pollution,overheating or from a lack of current.

Unlike the majority of mayflies, Epeorus speciesaccomplish their transition from nymph to dunwhile still on the bottom of the stream. By the timethey reach the surface their bodies are fullyexpanded and three dimensional, like a self inflatingrubber raft. It takes another moment or two beforethey have the use of their wings.

The Quill GordonEpeorus pleuralis, family Heptageniidae, order Ephemeroptera

A Quill Gordon

The Hendrickson hatch is the homecoming of thefly-fishing season.There are other, earlier hatches,such as the little olives and the blue quills, certainly,and in some places the Gordon quills. ButEphemerella subvaria is the first big game of the year.After a winter of waiting for the season to kick off,no one who calls himself a fly fisher can possiblyremain on the sidelines.

An angler living in central New England mustmaintain a heightened state of awareness in theearly season. Only when leaves appear on the wildhoneysuckle shrubs do the Hendricksons begin tocome off.That’s as many as three weeks later onmy home waters than on the fertile rivers of northwestern Connecticut.The hatches there are explo-sive. I check web sites daily and make frequenttelephone calls. I preserve open spaces on my cal-endar.

Roy Steenrod, a New York state game wardenand the only person known to have received flytying instruction directly from the legendaryTheodore Gordon, was a direct link in the Catskillslineage of the dry fly. Steenrod designed a patternthat fish took consistently during the dense springhatches of E. subvaria in the Delaware River water-shed.The traditional dressing calls for fur dubbingfrom the urine stained belly of a vixen. He namedhis artificial fly after his friend Hendrickson, whothus became the namesake of an insect. It is to behoped that the gesture made no reference to theman’s appearance or personal habits.

Preston Jennings lumped several similarEphemerella species together "as a type," but inmodern terms only the female subvaria is properlycalled a Hendrickson. She is a rather dowdy thingwhose attire is limited to bland shades of tan, beigeand gray with the merest hints of olive.The morevividly hued male, which anglers will tell youhatches in separate microhabitats and at separatetimes, is called the Red Quill.

The HendricksonEphemerella subvaria, family Ephemerellidae, order Ephemeroptera

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The Hendrickson

39A second molt in the winged state is unique to theorder Ephemeroptera, which includes all of the up-winged insects that today are known as mayflies.Fly fishers call this true adult stage the "spinner,"and biologists call it the "imago." At mating timethe males swarm over the stream and wait for thefemales to arrive.They convene over habitat similarto that where the insects spent their lives as larvae,and where newly laid eggs will thrive. Some spin-ner swarms, like this flock of Ephemerella subvariamales, are quite thick, but if you’re not on the river,looking at the right place and in the right light,you might never see them.If you do find yourself standing streamside at mat-ing time, and chance to glance up to the air spaceabove you, you’ll see what appears to be a squadronof insects with tails spread wide and forelegs out-stretched, all facing upstream.They bob up anddown, like horses on a carousel, and occasionallydart downstream. Into this pack a female will fly,chose her mate, and couple with him.The embrac-ing pair slowly loses altitude, but manages toremain aloft until the act is complete. For the male,life has ended.Within the hour the female will layher eggs and she, too, will die.

The Hendrickson Spinner FallEphemerella subvaria, family Ephemerellidae, order Ephemeroptera

46 What intrigues most naturalists and flyfishers about the insect genus known onboth sides of the Atlantic as the"grannoms" is the bright green gooey ballof eggs that develops at the tip of the adultfemale abdomen soon after mating. It isthe single visible detail that is common toall species of Brachycentrus and that appearsin most patterns. Charles Bowkler intro-duced the Grannom wet fly to Englishanglers in 1780 with his book The Art ofAngling as an imitation of a caddis thatnow carries the "Latin" name Brachycentrussubnubilis.The nine species identified inthe New World are collectively and patri-otically known as American grannoms.They have other nicknames, too, like theshad fly and the Mother’s Day caddis, inhonor of other events that coincide withtheir appearance.

The majority of American species aresmall and have dark brown wings thatappear black under most lighting condi-tions.The Olive Dun, B. americanus, is theexception. It is the largest of thegrannoms, the last to emerge each season,and is the only species that appears onboth eastern and western rivers. It gets itsname from the color of its abdomen andits medium, dirty gray wings.

Equally intriguing, to me at any rate,are the habits of the Brachycentrus larvae.They build tapered cases with a squarecross section, adding progressively largerpieces of twiggy material as they grow,until they remind me of the taperedsmokestacks of some old New Englandmills.The same silk that they use as casebuilding mortar, and to secure themselvesto rocks as they forage on the thin layer ofalgae, provides a means of moving safelydownstream. In order to avoid being sweptaway, they tether one end of the silkencord to a rock and allow the current tocarry them down to the next, much theway a climber rappels down a step moun-tain cliff.

The spring mating swarms ofBrachycentrus on the Catskills rivers werehistorically so dense that they rated a men-tion in the pioneering works of bothRhead and Jennings at a time whenmayflies were commanding all the atten-tion. Both writers remained frustrated intheir efforts to find a suitable match forthe natural. Either they failed to draw thedistinction between an emerging caddisand one that was laying its eggs, or theyhad become so much a part of the dry flycult that any return to subsurface patternswould have been considered an act of bar-barism.When clouds of Olive duns appearover the stream they are merely the visibleprecursor of the remarkable event that isshortly to take place under water.Adultfemales swim beneath the surface to pastetheir eggs on any stationary object theymight encounter, whether it be vegetable,mineral, neoprene or Gore-Tex. In orderto experience this phenomenon first handyou have to stand in a river wearingwaders.You may be hardly aware of theirpresence until the moment you leave thewater and discover that they have liberallygarnished your waders with sticky greenspots. Many is the time that I have cast dryflies to the few small trout rising toemerging sulphurs and remained obliviousto the intense feeding activity taking placejust beneath the surface.

The Olive Dun CaddisBrachycentrus americanus, family Brachycentridae, order Trichoptera

7574 The first time I ever laid eyes on a dobsonfly Iknew instantly what she was. For starters, she washuge, 80 millimeters from head to folded wing tip,nearly twice the length of the largest stonefly.Asshe moved she dragged her wings like the eyefeathers of a peacock or the train of a royal gown.And in place of the long, gently curving mandiblesused by the male for courting or for chasing offother males, this female brandished the shorter,scimitar shaped pair that is an exact replica of thoseseen on the dobsonfly larva, the hellgrammite.

I had that very evening been photographing ahellgrammite, and lamenting the fact that I had asyet never seen, much less photographed, an adult,when I saw her hanging on one of the black-outcurtains in my studio. She had flown in throughthe open window. Her abdomen was withered, and the tips of her wings slightly tattered, so I guessed

that she had just recently deposited her eggs some-where over the Mascoma River that flows outside.She moved sluggishly, as have all of the dobsonflies that I have since encountered, but when proddedor annoyed she would rise up in anger and respondwith a ferocious counterattack.The larvae are vora-cious predators, common to the substrate of fast,clear streams. Bait fisherman like them becausethey stay well on the hook and squirm in a tanta-lizing way.The adults are of little interest to fisher-man of any kind except as an extreme annoyance. Ihave heard about, but thankfully never experi-enced, their painful bites on the backs of unpro-tected necks. Both winged emergence andovipositing take place out of the water.The larvaecrawl out to pupate in the mud and silt beside thestream.When they emerge to unfold their wingsfor the first time and take to the air dobsonflies area truly majestic sight.The adult females lay theireggs on overhanging objects like tree branches orbridges.When the new larvae hatch they drop intothe water and the cycle begins anew.

The DobsonflyCorydalus cornutus, family Corydalidae, order Megaloptera

76 No mayfly undergoes a more spectacular transfor-mation in molting from dun to spinner than theeastern green drake.This giant among streamdwelling Ephemeroptera loses all but a hint of itsnominal wing color and completely sheds thebrownish dorsal covering of its abdomen to reveal asimplified palette of rich, dark brown and a ghostly,pale cream. In the males, with telescoping legs andtails, the effect is especially dramatic.It is the stuff of legend.Traditionally, the greendrake hatch was the height of the eastern fly fisher’sseason, with a reputation for bringing up large fish.When word of the hatch reached Manhattan, exec-utives cancelled appointments or called in sick.Baggage compartments overflowed with rod cases,and Catskills lodgings became scarce.

Alas, like many legends, its luster is fading.Today, few anglers have even seen a green drake orits funereal imago.Any creature that lives in thesediment of rivers is at the mercy of the man-madepoisons that collect there. Industrial selfishnessnumerous populations of this grand insect. Effortsto transplant freshly laid eggs to recovering envi-ronments, although heroic, have been largelyunsuccessful.

Harold McMillan led me to this Coffin fly at aprivate game preserve in upper New York State.There were no bugs until twilight, and then theyrained down by the hundreds. Large fish lost anysemblance of caution, and Harold caught one afteranother while I gathered samples for my camera.The battery on my portable light failed. Had thelodge not been nearby, closed but with an outdooroutlet, I could never have made the picture.

The Coffin FlyEphemera guttulata, family Ephemeridae, order Ephemeroptera

Dette Coffin Fly

115The portable homes of caddises belongingto the family Limnephilidae, known toanglers and naturalists as the northerncasemakers, are frequently described as"rough hewn," as if they had the case-building instinct, but lacked either the tal-ent or skill possessed by more highlyevolved families.The larvae of the genusPlatycentropus, and of a few of the 100species of Limnephilus, build theirs of tinysticks, pebbles and bits of weed, all layeredcrosswise, like a crudely woven basket, incontrast to the lengthwise arrangementpreferred by others. Such cases are believedto have been the model for a now classicfly pattern, the Strawman nymph. PaulYoung, a Detroit taxidermist, fly tier androd maker acclaimed as the "Stradivarius ofthe midge rod," used it to catch fish feed-ing on caddis larvae when surging currentsknocked them loose from the safer, quietmargins of Midwestern rivers and pro-pelled them helplessly downstream.

I have found the larvae ofPlatycentropus in a few New England rivers,but I am more accustomed to finding theclumped cases of the smaller Limnephilusspecies in the shallows of lakes and ponds,and especially in backwaters baked by thesummer sun until they are warm enoughto bathe in.The heat doesn’t seem tobother them as it would most insects intheir aquatic phase. In fact, they are sohardy that when I placed one in a box todry, as part of a collection I was to send toa boy scout in Pennsylvania it remainedalive and moving for three days.And yet inspite of their determination to endure Ihave only once, after numerous attempts,succeeded in raising a Limnephilus

to the winged stage. It hatched on amorning in early September, the solitarysurvivor from a handful of larvae that Ihad transported from a central Mainepond in June.

The caddis family Limnephilidae isby far the largest in North America, withover 300 species, including several that aretranscontinental and some, like theOctober caddis (Dicosmoecus) of the westand the great orange caddis (Pycnopsyche)of the east, that are among the most antici-pated hatches of the fly fisher's season.Because entomologists are continuallyplucking here and there from the almost50 genera and reassigning them to entirelynew families, the number keeps changing.

The StrawmanLimnephilus infernalis, family Limnephilidae, order Trichoptera

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Paul Young’s strawman nymph

Limnephilus infernalis adult caddis