The wide tidal river carried the soft light of a half moon. The horizon was an inky silhouette, masking tawny marshes and the loblolly pines that rose behind them. As we stood in the deepening darkness, confusion about a chaotic world slid away on the gentle current.

We were tired, but the beguiling spring night had its hold on us. This sweet evening trumped even the lure of a relaxing shower and soft bed.

A solitary dog barked in the distance. Closer, a pair of barred owls started calling back and forth, "who, who, who cooks for you?" The constant low thrum of insects provided the background music. Much closer, in the oaks just across the one-lane road, a high-pitched whinny startled us. The image of a horse roosting on a sturdy limb caused us both to break into wide-eyed grins. The call came again-a distinct, downward-inflected whinny.

The Eastern screech owl (Megascops asio) has an unusual vocal repertoire for an owl. Whinnies, rasps, barks, trills, screeches, laughs and even an occasional hoot can be heard from these year-round residents of Chesapeake woods.

Like most owls, the screech is primarily nocturnal, conducting its life under the cover of darkness.

When the sun goes down, the air and earth gradually give up their warmth. The air calms, clouds dissipate, winds die. The marshes and woods are far from silent, but a quietness envelops them, making each sound distinct.

Owls are well-adapted to this dark and quiet world. Facial feathers form a characteristic disk around the screech owl's face. The rustle of a vole in the grass is captured by that disk and funneled to the bird's ears. A moment later, it will take to the air on short, rounded wings. The leading edges of the flight feathers have a soft, comblike shape that muffles the sound of the owl as it swoops in on its prey. Bright yellow eyes dilate fully in the dim light, allowing the bird to see the prey that its hearing detected.

Small rodents, frogs and even songbirds are parts of the Eastern screech owl's diet. The bird catches insects on the wing and eats a variety of foods as part of its omnivorous diet.

The Eastern screech owl often uses its sharply down-turned, yellow-green bill to bite through the spinal cord of its victim, then ingests its meal whole. The stomach compacts the inedible bones and fur or feathers into a dense pellet. Back on its roost eight hours later, the owl will regurgitate the pellet. A series of these pellets under a tree is a sure sign that it is a favorite roosting site.

Eastern screech owls are permanent residents in their range. They can be found in wooded areas ranging from forests and river bottoms to parks and even suburban yards. They live from Montana south to Texas and east to the Atlantic, including the entire Chesapeake basin. Its close relative, the Western screech owl, has a range that slightly overlaps in the High Plains.

At 8.5 inches, the eastern screech owl is smaller than a robin. It has the erect posture and ear tufts that are common to its family. The birds show significant variation in color, ranging from rufous to gray with an uncommon intermediate brown morph. They are heavily streaked, giving a mottled appearance that serves as camouflage.

A week earlier we had seen an Eastern screech owl in the middle of the day. It wasn't roosting in a tree, but sleeping contentedly in a wood duck box at a nearby wildlife refuge.

Screech owls don't build nests. Instead, they take over abandoned nests from other birds, especially cavity builders like woodpeckers, or use appropriately sized bird boxes. They use no nesting materials.

The female lays her eggs on the bottom of the box or in the abandoned nest. She incubates the eggs for about three weeks, with the male keeping her supplied with food. Once the chicks hatch, they will take several days to fledge.

They remain dependent on both parents for food and hunting instructions for a few months. By fall, the youngsters will leave their natal site to stake out their own territory. Screech owls are monogamous and produce one brood annually.

The whinnying had stopped. In the silence, I imagined the screech owl swooping stealthily onto an unsuspecting field mouse.

Eventually, I would yield to the pull of the bed and the black silence of sleep. For the Eastern screech owl, the night was just coming alive with a rich array of nocturnal sights and sounds. This unfolding dark and silent drama is a compelling counterpoint to the glaring complexity of my days.