A gentle breeze tantalized us with the smell of damp, fertile soil and that hint of green that signifies the true onset of spring. The brilliant sunshine made the 50-degree temperature feel positively balmy.

For the last hour, a threatening cloud bank had been inexorably closing in on us, and we knew this moment wouldn't last forever. Finally, inevitably, the clouds swallowed the sun. The breeze took on a biting edge and the radiant warmth quickly abandoned the spring day, plunging us back into winter.

The birds soaring out over the emergent green farm didn't take offense. Their lazy circles slipped across the sky, pushed along by the northwesterly wind.

The two-toned wings arched above the raptors' backs, forming a shallow vee. From below, the leading edge of the wings was black, as was the body. The trailing edge of the wings was a silvery white.

A couple of the birds had dropped to a lower altitude. We could see their smallish, bald red heads. Most people would agree: These birds were big, but they weren't pretty.

Turkey vultures (Cathartes aura) are hard to miss. A wingspan of nearly 6 feet makes them one of the largest birds in North America. And they aren't shy. They will congregate around a freshly killed animal near the road side, and they often roost in large numbers in trees, atop barns and even on suburban roofs.

The birds are year-round residents in the southeast United States, including much of the Chesapeake basin. As we enter the late spring, some of these vultures will head north. Their summer range includes the Great Lakes, southern Canada and most of the lower 48 states. Year-round populations exist throughout Central and South America.

Turkey vultures can be found in searingly hot places, and their predominant dark coloring readily absorbs the heat. To help cool off, the birds sometimes urinate on their legs. As the urine evaporates, it helps the birds radiate excess heat. It's an effective cooling system, if not elegant.

While some birds like eagles and owls are noted for their visual acuity, turkey vultures use their amazing sense of smell to find fresh carrion. For the turkey vulture, the stench of death is a dinner bell.

When a vulture finds its prize, it will use its large white bill to tear its meal to shreds. The bald, red head lacks feathers, which would otherwise become fouled with rotting flesh. The vulture lacks strong talons, so it cannot capture live prey or use its feet very effectively to rip apart its meals. Thus, it feeds only on carrion.

Turkey vultures don't build nests. Instead, they use a secluded rocky ledge or hollowed-out log. The female incubates an egg or two, taking good care of the eggs, and later the chicks, for several months. Except while parenting, turkey vultures are gregarious birds. They are often seen drifting through the sky in circles, using rising thermals to help them soar over a vast territory in search of food. In the evenings, the birds congregate in large, communal roosts. Many a suburban homeowner has been vexed when vultures decide the backyard tree is a great roosting site. They can look ominous, but owners are usually more upset by the large piles of odorous excrement the big birds leave behind. Disgruntled suburbanites should be wary: A turkey vulture can intentionally vomit strong stomach acids if threatened.

For many people, turkey vultures are hard birds to like. They are considered ugly, threatening, and they practice a host of disgusting behaviors. We would be hard-pressed to get along without them, though. They are extraordinarily effective at removing carrion from the landscape. In doing so, they remove potential sources of diseases and keep decaying carcasses out of water supplies.

In some cultures, the birds are revered. Traditional Tibetan Buddhists practice "sky burials." In this ritual, the body of a deceased family member is taken to a remote area and simply left in the open. Vultures frequent these locations. It is not uncommon for the birds to begin dismembering the corpse while the family sits nearby, reciting prayers and bearing witness to the first stages of a new reincarnation.

The scientific name of the turkey vulture, Cathartes aura, means "purifying breeze," and beautifully captures this other view of the vulture.

Like the inexorable cloud bearing down on us, death will not be denied. We can try to ignore it or burden it with cultural taboos. There is wisdom, though, in learning to accept it with wonder and interest and even celebrate its natural role in our world.

The same may be said of the turkey vulture. It is a vital part of the ecosystem and has found extraordinary ways to adapt to its unique role. I find that intriguing and even worth celebrating.