It's the puzzle that draws me back to the stream as much as anything else. The trout are there. I can see their rise forms, concentric circles expanding outward from where a fish has taken a bug, but are they feeding on mayflies, caddis or stoneflies, or maybe it's flying ants, perhaps beetles in season?
There are those days when the hatches of aquatic insects overlap, making it especially confusing. Sulphers, easily spotted because of their yellow bodies, may be on the water at the same time as another, smaller, more non-descript mayfly, one with an olive body and dun-colored wings known as a blue-winged olive while hovering overhead like tiny tan helicopters may be caddis flies.
Other times only the occasional insect can be found, a few fluttering through the air, some riding the current. If you're lucky, a hatch may begin, slowly at first, with mayflies or caddis rising from the bottom of the stream, now appearing on the surface, until suddenly they emerge in sufficient numbers to rouse the fish into action.
If deciphering the bug de jour isn't difficult enough, a fly fisher must also determine what stage of the insect's life has triggered the trout's interest. So what's a brother of the angle to do? How to decide which fly to choose when the fish are looking toward the surface for their food?
If living in the eighteen hundreds, you might rely upon an analytical approach advocated by Sherlock Holmes. Elementary my dear Watson. Today's anglers might prefer the methods of television's diagnostic genius, the insufferable Gregory House, although those of us over the age of fifty may still hear the words attributable to Joe Friday, the taciturn Sergeant of the nineteen-fifties police drama, "Just the facts, Ma'am, just the facts."
Like Holmes, House and Sergeant Friday, the fly fisher must observe the stream and its surroundings for clues while keeping an open mind for the unexpected. Before tying a fly to your tippet, check the facts. Take a few moments to observe the water and the air. Examine streamside spider webs and the leaves of bushes and trees. Another way to ascertain which fly to use is to watch how the fish are feeding. Are they sipping their meals or gulping them down? Perhaps they only appear to be rising to the surface.
Sometimes the type of rise form can help solve the afternoon's dilemma. Trout that slash at the water are usually chasing caddis, which swim rapidly upward from the stream bottom flying into the air without hesitation. In an effort to grab these aquatic insects before they escape skyward, some fish will explode through the surface. Listening is also helpful. A series of slurps, pops or splashes may also signal trout chasing caddis.
On the other hand, dimples and depressions are more likely a sign that the trout are feeding on mayflies. Unlike caddis, mayflies must struggle to emerge. Afterward, they ride the current while drying their wings, which stand upright like tiny sails. They are vulnerable during both stages of their development allowing hungry trout to feed upon them at their leisure.
Look at that big brown trout. There, in the deep run above the bridge on the Big Flatbrook. See how its mouth methodically breaks through the surface, every few seconds, rising silently, sipping mayfly duns drifting down with the current, ignoring those that float an inch or more from where the large fish is holding?
And over there, farther up the river, beyond the large boulder where the river slows, can you see that fish, the depression it leaves? Notice how only the dorsal fin breaks through the surface. It too is feeding on mayflies, but these are only beginning to emerge from their nymphal skins and are still under the water.
In April, mayflies tend to hatch in the afternoon, usually after twelve, on those colder, damper days when the skies are overcast, not until two and sometimes later. Blue Quills, Quill Gordons and Hendrickson patterns can be used to match the principal mayfly hatches as the month proceeds. Be sure to have a few of each in sizes #14 and #16 when fishing the larger streams of Warren County such as the Pequest, Paulinskill or Flatbrook or if out on the rivers flowing through Sussex County, perhaps the Musconetcong or Ken Lockwood Gorge on the South Branch of the Raritan. Hatches can be prolific with one, two or all three of these mayflies riding the current at same time.
I prefer patterns tied with a parachute wing to imitate the duns, but always carry a few emergers. Don't be afraid to switch flies if the one you are using isn't working. Sometimes going down a size helps. Other times switching from a pattern that resembles the dun to one that imitates the emerger will do the trick. Don't be discouraged if you find yourself surrounded by rising trout, the fish gobbling down the naturals while ignoring your imitation. Experiment. Have fun. There's always tomorrow and the day after that. The trick is to observe and learn as much from your failure as your success. After all, Doctor House gets it wrong most of the time, taking the entire hour before finally diagnosing his patient's problem.
Later in the day, after the hatch has abated and many anglers have retired from the stream, you might spot a swarm of bugs undulating in the air. They're mayflies that are mating. Soon the males will fall dead, their wings flush with the surface making them nearly invisible to the angler. The trout, however, will spend hours gently sipping these "spinners" from the slower stretches, in the back eddies and along the edges of quiet banks where these nearly invisible morsels tend to collect. This provides an opportunity to extend your time on the water. Think about using a spent-wing pattern after a hatch has ended, or in the morning, before a hatch has developed, to fool trout that may be feeding on spinners left over from the previous afternoon.
So there you are staring down at a season's worth of flies tucked into clear plastic boxes scattered in the back of your SUV. It's the third week in April, around two in the afternoon, the temperature hovering in the high forties, skies overcast, threatening rain once again. Placing the box marked Quills into your fly vest, you lace up your boots, buckle your waders and tramp toward the stream. The river is running a bit high, the current fast, but clear as it sweeps down into your favorite pool.
"Sam Peabody, Peabody, Peabody." Sitting on the bank, you listen to a white-throated sparrow flitting among the prickly branches of a nearby barberry while watching and waiting, waiting for some sign that the stream is alive. After a few moments, a phoebe swings down from an overhanging branch and swipes an insect from the air. You step onto a shoal where a colony of coltsfoot, its dandelion-like flowers in bloom, spreads over the grit and gravel. A bug flutters by, or was it a dun-colored mirage? Then, like Pharaoh's ships, their dun-colored sails tacking in the breeze, a fleet of mayflies drifts down with the current while along the far bank, near the back of the run, the slightest of dimples permeates the surface, a series of rings emanating outward as a familiar tune comes to mind. You know the one. Goes something like: