Blades dipped and the obliging kayaks slipped through the yielding waters. The soft shush of river water gliding by the bow kept time with the rhythmic pull of our paddles.

Beltway traffic and city buses were just jangled memories here, replaced by the steady gain-and-fade of a solitary car's tires on rural roads. Earlier, we had heard the whine of a single Evinrude and the slap of its wake as it rolled down the river like some noisy, mechanical tide.

The Vulcan, a river tug, chugged upriver that morning, pushing an empty barge. The big boat towered over everything else on the river, with a rugged powerful look about it: all throbbing engine and bulky steel. The rarity of the sight made it worth stopping for.

As we pushed deeper into the marshes, even these final vestiges of man-made noises were slowly erased. All that was left was nature's soundtrack. Birds called and sang against the steady thrum of insects. A muskrat rattled through the reeds. A turtle plopped, sliding from a sun-draped log into the safety of the water.

The cacophony of the city had given way to the marsh's mellow rhythms.

The peaceful scene was punctuated by a clear "wheep!" and a flash of yellow. The bird was into the woods before I could get a good look. I eased the kayak around a profusion of pickerelweed and out of the gentle current. Facing directly into the trees, I was just a few yards away from a riverbank of loblolly pines, oaks and laurel.

I wasn't sure where to look when a sharp, rising "wheep!" announced the bird's location. A great-crested flycatcher (Myiarchus crinitus) perched in the cavity of a dead red oak, with most of its body visible through the nesting hole.

Great-cresteds are the only flycatchers in the Eastern United States that use nesting cavities. I was looking at an adult, with a bulky brown crest, gray neck and breast, and bright yellow belly.

Invisible to me from this vantage point, the undersides of its wings were also yellow. From the top, the bird would appear mostly brown, with a rufous tail. The wings would show a bit of rust along with white wing bars. The bird's dark bill is relatively heavy and wide - perfectly suited for snatching insects.

The great-crested flycatcher I was watching dropped back into the tree hole and out of sight. The cavity would be filled with any manner of materials, ranging from bits of plastic and string to other trash scavenged during nest construction. The birds use natural cavities or holes excavated in prior years by woodpeckers. The flycatcher then adds whatever materials are needed to fill the void to a comfortable size.

Nest building, such as it is, is done by the female. She might use a bluebird box instead, if one is handy.

These flycatchers are noted for lining their nests with snake skins. Theories abound, but ornithologists don't know why the birds exhibit this behavior.

During the breeding season, great-crested flycatchers inhabit wooded areas in the eastern half of the United States and the southern portions of adjacent Canadian provinces. During winter, a few birds will decamp to south Florida, but the vast majority spend the non-breeding months in the tropics.

These flycatchers sally for insects in the tree canopy, snagging unsuspecting bugs off leaves and stems. They also hawk for insects on the ground. Small fruits make up a portion of the flycatcher's diet, but the focus, as their name implies, is on a diet of flies.

Far off to the right, I heard the "wheep!" of a second bird. This time, I easily spotted its prominent buttery belly and underwings. Perched on a bare branch, the great-crested flycatcher stood erect. The relatively large, crested head dwarfed the slim body and longish tail. I glanced back and the original bird had stuck its head out, perhaps curious about that call.

Was that single, rising note issued as a warning? Or, was it a new bird staking claim to some other bird's territory?

The avian meaning was lost on me, but I was captivated by that self-assured call note, given so emphatically. Why can't people speak with equal clarity and precision, I found myself wondering.

Here in the marsh, the voices come with few distractions. I hear the great-crested flycatcher call again and realize that it's not the clarion note that I most appreciate. It's the vast soundscape that allows individual voices to be heard and time enough to listen.

The city is an orchestra of a hundred instruments, all alive with an avalanche of notes. The marsh is a jazz combo with plenty of time for each musician to take a solo spot.

Personally, I'll take the jazz.