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Killer Bug

Killer Bug

Fountains of Youth – Classic trout flies that have withstood the test of time … flies that remain “forever young”

by Rusty Dunn

A 21-year old Englishman is hired in 1928 to manage and improve six miles of trout water on the River Avon.  The task before him is immense, for the river has suffered years of neglect.  It was once a premier trout fishery, but is now choked with weeds, smoth­ered in silt, and home to more trash fish than trout.  Natural repro­duction of trout is near zero, and fishing is sustained only by hatchery transplants.  The young river keeper undertakes his job with determi­nation and persistence, not realizing that the task will occupy him for 52 years.

By careful ob­servation of trout, insects, and the river’s many in­habitants, this self-taught river keeper devel­ops stream management techniques that slowly but surely improve trout habitat of the river.  He first re­plenishes the food base by restoring insect hab­itat.  He then restores clean spawning gravel in both the river and its tributary creeks.  He nets, traps, elec­tro­shocks, and removes thousands upon thou­sands of undesirable fish that feed on trout or compete with trout for the availa­ble food.

The keeper is a keen fly an­gler who believes that catching unwanted fish with rod and line is more sporting than removal en masse.  He is also an accomplished fly tyer, and he develops an artificial fly that is remarkably effective for removal of one par­ticularly abundant and bother­some species of trash fish.  Using that fly alone, the keeper can remove dozens – even hundreds – of undesir­ables in a single afternoon.  Lit­tle by little, the river re­turns to promi­nence as a wild trout fishery, and the humble river keeper becomes one history’s most re­vered anglers, authors, and river managers.

The river keeper of this true story is Frank Sawyer, originator of the Sawyer Pheasant Tail Nymph, which is arguably the greatest trout fly of all time.  Sawyer’s second most famous fly is his Killer Bug, which he developed to remove European grayling (Thymallus thymallus) from the river.  Grayling are ac­corded more respect today than in Sawyer’s era, when they were viewed by most English anglers as unwel­come intrud­ers to be eradicated when pos­sible.  Sawyer tied his Killer Bug to imitate the abundant River Avon scuds, but it also imitates cranefly larvae, cad­disfly larvae, and many aquatic beetles equally well.  Sawyer had an un­canny ability to spot fish underwater, and he could tar­get with a Killer Bug a single grayling mixed among trout and catch it within a couple of casts.  Sawyer orig­i­nally called his fly the “grayling lure”, in deference to its utilitarian pur­poses.  Sawyer later introduced the pattern to Lee Wulff, who tested it with great success on North American rivers and per­suaded Saw­yer to rename it as the “Killer Bug”.  Indeed, the fly is a killer when presented to either trout or grayling.

Like all of Saw­yer’s patterns, the Killer Bug is remarka­bly simple.  It contains but two ingredients, which Saw­yer described as “a miserable concoction of wire and wool … which to the human eye has not the slight­est resemblance to any living creature.”  To a trout’s eye, however, the Killer Bug must look rather delicious.

Sawyer tied his Killer Bug of Chadwick’s Wool & Nylon Mending Yarn, colour 477, which he described as a “fawn background that has a definite pink tinge“.  He stated that the yarn “is not very easy to obtain“, but it became impossible to obtain when Chad­wick’s ceased production of colour 477 in 1965.  The fly-tying world is still recovering from the disaster, and re­maining lengths of Chadwick’s 477 now sell for exorbitant sums.  It has mythical status and a cult fol­lowing, much like polar bear hair, urine-stained under­belly of vixen red fox, creamy yellow scrotum fur of a white ram, and so forth.  Fortunately, satisfactory sub­stitutes are readi­ly available.  Indeed, many con­nois­seurs of Killer Bugs seem to have their own favor­ite yarn.  Pre­senting a faux-Chadwick’s Killer Bug in the right place, at the right time, and with the right be­hav­ior is far more im­portant than matching Sawyer’s exact color.  That is, unless you believe in the magic of a mystical tying mate­rial and the spirits of a legendary river keeper.

Copyright 2022, Rusty Dunn


Killer Bug

Killer Bug

Hook: Wet fly / nymph hook, #6 – #16
Thread: None; tied only with fine copper wire.
Underbody: Fine reddish copper wire; build a cigar shaped underbody, leaving several turns of wire as a tag at the hook bend.
Body: Chadwick’s #477 wool wrapped thinly over the wire underbody.  The reddish color of the underbody should show through overlying wool, thereby imitating translu­cency.  The fly turns faintly pink when wet.