Fly Fisherman Throwback: Anting The Hatch

Editor's note: Flyfisherman.com will periodically be posting articles written and published before the Internet, from the Fly Fisherman magazine print archives. The wit and wisdom from legendary fly-fishing writers like Ernest Schwiebert, Gary LaFontaine, Lee and Joan Wulff, Lefty Kreh, Robert Traver, Dave Whitlock, Al Caucci & Bob Nastasi, Vince Marinaro, Doug Swisher & Carl Richards, Nick Lyons, and many more deserve a second life. These articles are reprinted here exactly as published in their day and may contain information, philosophies, or language that reveals a different time and age. This should be used for historical purposes only.

This article originally appeared in the July/October 1982 issue of Fly Fisherman. Click here for a PDF of the print version of "Anting the Hatch"

---

The shallow, weed-filled flats were carpeted with tiny mayflies and the river's placid surface was dimpled with the riseforms of countless feeding trout. As I waded carefully into position, I noted a school of trout working slowly upstream, feeding eagerly on the parade of emerging nymphs and duns. The fish moved into casting range and I picked a large one and carefully cast my fly just above its last rise. The trout took several naturals in languid porpoising rises as my fly drifted down. When it reached the fish, it too disappeared in an unhesitating head-and-shoulder rise. I tightened and the fish bolted downstream, scattering the other fish as it went. Its run took the trout into the backing, and after two leaps and another long run I brought the fat sixteen-inch rainbow to net and carefully released it.

Such a heavy emergence of small mayflies, the slow-moving water and the sophisticated trout seemed, at first glance, to call for classical hatch matching. But the artificial I tied on that morning bore no resemblance to the naturals, and the weather was wrong for the pattern I used. The mayflies that blanketed the water were tiny Tricorythodes duns, calling for a #22 imitation. I was fishing in the midst of a heavy snowstorm and the weather extended the Trico dun emergence well into the early afternoon. The mayflies left the water very slowly–easy prey for Henrys Fork rainbows. The fly I chose was a #16 Red Fur Ant. Although this contrasted sharply with the tiny mayflies, I took forty "sophisticated" rainbow before the cold drove me from the water.

My fly choice that day was based neither on whim nor desperation. I have found that, under the proper conditions, using an ant imitation in the midst of a blanket hatch can be an effective strategy.

"Mismatching the hatch" is an old idea, and trout are known to eat ants with great relish. However, mismatching the hatch is often a desperation move, used only when fish have refused all possible natural imitations. Pattern choice is often based on angler whim-trying something that has taken trout before, often an attractor pattern such as a Royal Coachman or a Variant. Although this technique sometimes succeeds on small trout, it usually fails on large, more circumspect fish.

Artificial ants are an important weapon for the modern fly fisher, who generally calls on them in one of two situations. When there are innumerable winged ants in the air and on the water, conventional dry flies are useless, but an ant pattern is readily accepted. Ants are also used in late season, when hatches are infrequent and sparse. There are few patterns as effective as ants during this season.

But, despite the general effectiveness of ant imitations, few fishermen advocate the use of an ant pattern during heavy mayfly or caddis hatches, particularly when large, selective trout are the quarry. It took two widely spaced incidents to convince me that anting a hatch can be effective, and I now regard this technique as an ace in the hole for taking large trout on dry flies.

Trout had been feeding steadily on a good hatch of Pale Morning Duns one warm May morning on California's Hot Creek, but I was having difficulty.

Although an occasional small rainbow fell to my dun and emerging-nymph imitations, the big browns showed no interest. Out of desperation I worked feverishly through my fly boxes, eventually tying on a #12 Black Ant. With little hope of success, I launched the ant on its first drift and was astonished to see it disappear in a confident rise before the fly had floated a foot. I exercised several good browns with this pattern before leaving–the last a fine twenty-inch male.

I gave this incident no thought until a few years later, when a fish-filled August day on the Henrys Fork convinced me ants can be used with confidence during a heavy mayfly hatch. While working the Bonefish Flats section one morning, I noticed a light breeze blowing a reddish winged ant onto the water during a good Callibaetis spinner fall. Although I'd been using a polywing spinner successfully, it took a dozen or more perfect presentations to induce a rise. I tied on a #14 Red Fur Ant. The big rainbow took the pattern on virtually every good drift and the Red Fur Ant continued to produce even through the afternoon hatch of Ephemerella inermis.

Since then I have counted on anting the hatch in difficult conditions. I have found the ant strategy most effective on the largest surface­feeding fish, and there have been occasions when I have watched my ant drift unmolested past two or three small trout only to be taken by a large fish just downstream.

Anting the hatch is not an alternative to matching the hatch, but it can be a useful supplementary method under the proper conditions. Throughout the season it is most useful during heavy, small- to medium-size mayfly and midge hatches. It is less successful during caddis emergences, when trout concentrate on the caddis pupae rather than on the drifting adult. Anting success comes most often when trout are concentrating on small, freely drifting insects during ant seasons. Since most North American ants are active during daylight, anting the hatch is effective then, but less so during late evening hatches. I have taken trout on ants after midnight.

Why should anting the hatch work? Ants are dominant components of nearly every insect habitat on earth, and due to their wandering habits in search of food, they drop into the water when breezes stir bankside vegetation. Once helplessly trapped in the water's surface tension, ants are easy prey for fish. Their appearance in the water is irregular, but eventually trout learn they are tasty, which may account for the effectiveness of ants as mid- and late-season search patterns. In the absence of steady hatches, drifting ants may be of relatively high importance in a trout's diet.

Now picture a trout feeding on a heavy hatch of small late-season mayflies. The trout sees ants come by sporadically and takes advantage of them. An ant drifting overhead in the midst of a dense hatch is not an alien to the trout, and if the fish feeds on ants often it is likely to take one even in the midst of a hatch, particularly if the ant is larger than the hatching mayfly. Trout do not feed selectively merely to torment or amuse anglers, even though it seems that way at times. Selectivity is a behavioral adaptation that allows the trout to maximize its net energy intake per unit time. Like most predators, trout probably develop fairly specific "search images" when feeding on abundant prey. The search images allow the trout to concentrate their efforts on a specific prey item–the one most abundant or easiest to capture. When matching the hatch we, in effect, try to trigger the feeding response of the trout by simulating a search image to the fish. Anting a hatch probably works because trout have learned that ants are juicy tidbits that cannot escape capture. The ant's narrow waist also provides a distinctive search image for the trout.

Do trout develop a taste for ants? If so, it could account for anting the hatch success on older trout. Once a large trout is lured to the surface by a dense mayfly hatch it is unlikely to pass up a splendid–although different–morsel.

How selective are Henrys Fork trout during a hatch? Trout I've tested in the ten- to twelve-inch range are invariably filled with a single mayfly species, even if two or more species are on the water simultaneously. When more than one species is present in the stomach, it appears the trout switched preferences suddenly, since the flies are not mixed in the stomach. However, on the one occasion when I killed a large trout from that water I found the stomach contained not only large numbers of tiny Baetis nymphs but also two grasshoppers, a beetle, and a damselfly nymph. The 21-inch rainbow was taken on the first drift of a #16 Red Fur Ant after it passed up innumerable presentations of a #22 Baetis nymph imitation. Although merely suggestive, this evidence implies that large trout may sometimes be more opportunistic and hence less selective than smaller trout.

Although I have no conclusive evidence that trout develop a taste for ants, my experience last summer suggests it. Beginning in early July, certain Massachusetts tidal rivers host sea-run brown trout, which move into these rivers' lower reaches, evidently to avoid the warm estuaries, and feed near the river mouths. In early July I could not interest these trout in ant imitations, even though there were steady but irregular parades of naturals on the water. One mid-July morning a heavy fall of winged ants occurred, however, and the estuary surface was quickly carpeted with their bodies. About fifteen minutes into the fall I observed the first trout rise. It was almost an hour before the fish fed actively on the ants.

These trout became easy prey to a Fur Ant for the duration of the ant fall. More important, from that morning on these sea-run browns would take an artificial ant with no hesitation, even though drifting naturals were no more common than before the big "hatch." I concluded that the browns, so used to feeding on grass shrimp and minnows, learned that ants are good. The lesson left a strong imprint on their behavior.

Anting the hatch is a straightforward technique, involving only tying on an ant pattern and fishing it dead drift over a surface-feeding trout. Even trout actually feeding on nymphs just below the surface will often take the floating ant imitation with confidence. Merely substitute an appropriate ant imitation for the hatch-matching artificial and you're in business.

Simple dubbed-fur ant patterns are most effective. They consist of a large ball of dubbed fur for the abdomen and a smaller ball of dubbed fur for the thorax. A few turns of hackle, clipped below, are tied in over the narrow gap between the two balls of fur. Such patterns take just a few minutes to dress (including the time to mash the hook barb down and sharpen the point) and I have found them durable. These patterns duplicate two most important features in the naturals: the narrow-pinched waist and the translucence of the heavy abdomen. The increasingly popular balsa-bodied McMurray Ants are opaque and time-consuming to make, and I have found them less effective than fur-bodied patterns.

Although you can devote much effort to duplicating the exact shades and sizes of many important ant species, this approach does not seem worth the effort when anting the hatch. There is no question that trout can become selective during heavy winged­ant falls. But trout tastes seem to be catholic when they are anting the hatch. Three color combinations are sufficient for anting the hatches: red, black and red, and black, in sizes ranging from #10 to #18. Smaller ants are not as effective when anting the hatch, possibly because a large ant offers a larger meal when surrounded by smaller insects. For open meadow waters the red and black and Red Fur Ants are most effective and for forest streams the Black Fur Ant or Black McMurray Ant are best, perhaps because black carpenter ants are prevalent in forests and reddish harvester ants abound in meadows and on sage flats.

A light-wire hook enhances the floating properties of the fur ants, but I always keep a few flies dressed on heavy wet-fly hooks. Used in combination with a heavy tippet, these are handy for horsing big trout away from weedbeds. Even when liberally dosed with silicone these flies float poorly, but they remain effective even when they sink. I once spotted a huge rainbow feeding on emerging Baetis nymphs in a weed-choked reach of the Henrys Fork. I cut back to a 3X tippet and knotted on a #14 Red Fur Ant on a wet-fly hook before casting to him. A gust of wind plunked the fly down hard enough to make it sink, but I fished out the cast. When the leader paused in its drift, I tightened and set the hook. Although I was unable to turn the fish on its initial run, the stout tackle horsed him from the weeds to open water. The trout peeled off ten yards of backing before making a halfhearted jump, exposing over two feet of olive and rose flank, before the line fell sickeningly slack. Despite my failure to land the fish, the heavy-wire hook and stout tippet made the short fight and jump possible.

A drag-free drift is essential when anting the hatch. For long, drag-free floats I grease the line and leader heavily. The high-floating line and leader are less affected by subtle cross currents and they mend cleanly. For proper presentation the fly should drift over the trout in advance of the leader, so the tippet will not spook the fish. I use a limp nylon tippet at least four feet long, and sometimes as long as six feet, bringing the total leader length to sixteen feet or more. With this system it is virtually impossible to cast a straight leader. The leader falls loosely on the surface, floats high and imposes minimal drag on the fly. It also allows the use of heavy tippets, even with small flies. I rarely go below 5X, even when using flies as small as #22, and 4X is my standard when using a #16 Fur Ant. Since a 4X tippet in the new copolymer nylons may test 5 pounds, one can land large fish more quickly, greatly enhancing chances of fish survival after release.

Large fish feeding on a blanket hatch of small insects often do so in one of two ways. In quiet water some cruise about slowly, picking off insects at regular intervals but in unpredictable locations as they change direction. Other trout take up definite feeding stations from which they will not budge but feed sporadically. These fish make several rises in rapid succession with long pauses between each set of rises. In either situation, the angler must place the right fly in the right place at the right time. Even if you solve all these problems your artificial must compete with thousands of the naturals. When matching the hatch I've worked over good fish for a half hour or more before a take. Such times call for anting the hatch. Cruising fish often move to the plop of the Fur Ant and take it on the run. And fish feeding at stations sometimes take the fly on its first drag-free drift, even if it drifts by well out of their normal feeding rhythm and range.

Anting the hatch can considerably reduce your wait between hookups, putting on more and larger fish during a hatch that may be of relatively short duration. Although not all trout will go for an ant during a heavy hatch, enough will to make this an important trick in the fly fisher's arsenal.

---

Ken Miyata was a post-doctoral fellow at the Smithsonian Institution in Washington D.C. He studied the ecology and evolution of South American frogs and lizards.

---