The Catskill Fly Fishing
Center and Museum

This page was last updated on
August 14, 2003 3:40 PM

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Energy Considerations: The Flow Of Life Through The River


We wade the river at dusk, all the while unaware of the nocturnal stirrings happening all along the bottom (benthos) of the river. Each night, a potpourri of macro invertebrates rises into the water column and is carried en mass towards the foot of their home pool. Drift, unknown to aquatic biologists until recently, 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.


In the end, we only conserve what we love,

We will only love what we understand,

We will only understand what we are taught

............ Baba Dioum, Poet

 Copyright © 2003