Fig.57 Drift.jpg

Sheep skin fly patch crowded with under-appreciated, waterlogged bits of nothing. Last cast to the noise - the splash - not the fish. Nothing. No wonder I got no rise in the last 10 minutes; the wind knots in my leader with a fly entangled in it said it all. Ugly, real ugly! Disassembled rods and gravel-coated soggy waders are removed and stored away in dim light. Thoughts and smells of the river still fresh and flowing. Sunset clouds that jostled for center stage all day now glow iridescent whites, grays and pinks, their reflective surfaces give up one last light show. Linger longer. Delay trekking back to warmth and friendships that have gathered around the night fire. Throughout the day, parallel shafts of light focused onto the landscape below as so many spotlights on a stage. Darkness has taken over. Familiar forms transmutate into black tracings against the horizon of a deepening blue-black sky, assuming intimidating, depthless, sinister shapes. Mid-stream, distracted from the little rising fish in front of me, I watch as the transparent sky mellows into thick, clotted streaky reds and purples, all the while unaware of the nocturnal stirrings happening all along the bottom (benthos) of the river.

Each night, a poupouri of macroinvertebrates rises into the water column and is carried en mass towards the foot of their home pool. Drift (Figure 45) takes place in most freestone rivers twice a night, once about one hour after darkness, and again just before sun up. This behavior is believed to relate to food gathering of plankton and other small particulate food items, but it may also function to relieve the stress induced by competition due to overcrowding, as species mature and prepare for their fifteen minutes of fame; their moment in the sun. By daybreak, they have re-attached themselves to the bottom strata and have, incredible as it seems, crawled or swam back into their daytime niches from whence they came. Fish that feed on these invertebrates are attuned to the drift and align themselves at the lowest end of each large pool to gather in their effort-free meals. The largest fish of the river come out at night and begin their systematic search for food. Smaller fish now hide and try not to draw the attention of larger fish, or they will not be there at sunrise.

The knowledgeable wet fly fisher often does very well angling through the night (Figure 46). Some of the largest trout of any stream are caught during this time (see: Night Fishing For Trout: The Last Frontier, by JimBashline).


Figure 45. Diurnal drift pattern for Baetis nymphs.


Figure 46