It was the Hendricksons that hooked me on “match the hatch” fly fishing. The Hendrickson mayflies hatch during the afternoons from mid April to the end of the month on most streams in the mid Atlantic Region. At the age of twelve, standing along Standing Stone Creek in Central Pennsylvania, I was thrilled when I caught my first, beautiful, brown trout on a dry fly during a Hendrickson hatch. About seven years later, my friend, Greg, and I revisited that same stream and I experienced the joy of my first “real” hatch. We were lucky to have stumbled onto a goldmine of Hendricksons hatching off the water and a fish feeding frenzy. Needless to say, we went back the very next day. Armed with the knowledge we had gained the previous day, and a plan, and with our teenaged cockiness intact, we confidently arrived at the stream, and lay down on the bank to soak in the sun. We watched as several fishermen repeatedly slapped the water with their lines to no avail. Then, as we knew it would, the clock struck 2 and it happened. The Hendricksons came out in full force and so did the fish. We crushed ‘em. We caught so many, we lost count and the looks we got from the other fishermen, who were still slapping water, were priceless. I was hooked. Many years later, I’m now privileged to work on the Upper Delaware, which is one of the most famous trout rivers in America and happens to have a much longer Hendrickson hatch than most of the mid Atlantic Region. I enjoy witnessing large, wild trout feeding freely on these insects from about mid April into mid May.
What makes the Hendrickson, Emphemerella subvaria, hatches so special and memorable for so many anglers? The answer is; several things. The Hendrickson hatch occurs during the spring when most anglers are itching to get out into the fresh air and onto the water to cast to rising trout. The hatch occurs in the mid to late afternoon, which fits better into more anglers’ schedules and therefore more anglers are able to enjoy the event. The main reason it is so special, however, is that the lifecycle and habits of this mayfly cause it to be vulnerable to trout during all stages of its emergence and reproduction. Many great theories have been developed, applied and practiced during Hendrickson hatches. I’m grateful to have had the chance to fish with and learn from several of the sport’s greats, including Don Baylor, Al Caucci, and Ernie Schwiebert, all of whom impressed upon me the importance of knowing the habits of the insect you are trying to imitate. To understand the hatch and to successfully catch fish throughout its progression you need to understand the nymph, emerger, dun and spinner stages of the insect during the hatch.
The Hendrickson nymph lives primarily in gravel and cobble bottom areas of streams with a medium to medium fast current. Riffles, fast glides and slicks are good places to find them. Emphemerella nymphs are crawlers with feeble legs and substantial bodies. They are generally dark brown to almost black in color with a light tan spot on their abdomen and have three tails. When you find these nymphs with darkened and enlarged wing pads you can assume the hatch is starting or has been going on for a few days. The nymphs start to become more active in the afternoon, when the emergence process begins, and they will swim to the surface with a wiggling motion that is sure to catch the eye of any trout in the area. As the nymphs struggle to break free of there shucks they may swim up and down in the water current several times before the time is right to swim to the surface and emerge. This is the time to fish nymphs such as bead heads and more realistic patterns in the riffles and in the heads of pools. Trout will be gathering in these areas, keying in on the size shape and color of the nymph and feeding on the abundant food source. A good dead drift can be deadly on its own, but a little motion imparted to the fly at the end of the drift can put a jolt in the line from an aggressive fish. Remember to adjust your weight according to the depth of the run and that, as the insect activity increases the fish may start feeding higher up in the water column, if you are fishing in deeper water.
As the Hendrickson emerger splits out of its exoskeleton or shuck, it is extremely vulnerable in the water’s surface film. This is when the trout will take advantage of the easiest pickings. The Hendrickson is temporarily stuck in the film while it finishes its emergence and becomes ready for flight. Wise trout sense this and feed eagerly on emergers throughout the hatch. Emergers and Cripple patterns fished with a perfect drag-free drift are rarely refused, even by the most sophisticated trout.
After the dun has split away from its shuck, it still must rest and dry its wings on the water’s surface. This is why you often see flotillas of Hendrickson duns or adults floating along the current seams in pools and fish lined up to suck them down. In the cooler spring air and on cloudy days, it often takes a couple of minutes for a Hendrickson to get airborne and the trout take full advantage of the situation. Flush floating dry flies such as thorax duns and compara duns come into play in this situation. As the insect starts to flutter or approaches faster water, the traditional, fully hackled, Catskill patterns become more effective. Again the cast and presentation become the keys to success in the clear waters of a pool and will dictate the achievement of the fisherman. Most of the emergence activity will occur between 2:00 and 4:00 PM.
As the sun begins to lower in the sky and evening approaches, a wise angler will keep one eye on the sky to look for the spinner or mating flight to begin while he is fishing. Hendricksons tend to gather over riffles to mate and deposit their eggs into the stream. As the flight occurs and the insects begin to die, they land in masses on the water and become a sure meal for the trout. The spent insects float perfectly on the currents with no chance of escape. The trout will line up on the current seams and use them as conveyor belts of food for the next couple of hours. Perfect imitations and drifts can take many trout as they tilt their bodies toward the surface and gently sip in the spinners. Trout feeding on spinners, expend little energy and only make gentle rings when they feed. They will not chase down a spinner when they know that another is coming in just a matter of seconds, so accuracy and presentation is again of the utmost importance.
During the hatch you should have a variety of Hendrickson patterns, sized from 12 to 16 for each pattern, in order to match the different sizes and stages of the insect. Nymphs should be dark and have robust bodies, such as a dark hare’s ear or a compara nymph. Emergers and cripples work best with dark tan to brown colored bodies and dun colored wings. They should ride low in the surface film and have wings or trailing shucks that touch the water, characteristics which show the trout that they are easy prey. Duns fished in slower pools should float with their bodies flush in the water like compara dun or thorax patterns and fully hackled, Catskill patterns are better fished in the faster water or to cruising trout. Male Hendericksons are brown to reddish brown in color, while female Hendricksons are tan to pinkinsh tan in color, both have dun colored wings. It is wise to have both color options from which to choose for those particularly selective trout. The last fly needed in a good selection is a spinner with a dark brown body. A rusty spinner or compara spinner with dark brown dubbing will serve most anglers well.
The Hendrickson hatch is what many of us will see on opening day or during the first couple of weeks of trout season in our area. The trout thoroughly enjoy this season of plenty and seem to be just a little more vulnerable during this time. Once you are properly prepared, and as you become familiar with the insect lifecycle and how each stage appeals to the trout, you will become much more successful at catching fish and may even get to experience the joy of receiving some of your very own priceless looks.