Small, brilliantly colored, fearless, a remarkable mode of flight and native to the Americas -- all of those words describe hummingbirds.

Five-foot five, brown hair, energetic, bird lover and naturalist. Those words describe Susan Campbell.

What do these two have in common? Less than 100 people in the United States are licensed to band hummingbirds, and Campbell is one of them.

When the daylight hours begin to lengthen, and the air warms, it signals that spring will soon arrive. The trees and shrubs dress themselves in their bright green leaves, and the flower buds begin to swell. It is the season of renewal.

The changing light and temperatures also signal the creatures of nature, for it is in late March and early April that the ruby-throat hummingbirds are stirred to return to the Sandhills after wintering in Mexico and Central America.

When they do, Campbell can be found at Weymouth Woods in Southern Pines, capturing these remarkable little birds, gathering data, and banding them.

The scouts, as they are called, are usually males, leaving their wintering grounds and heading north to their summer nesting areas. It is almost like they have GPS, for they return year after year to many of the same territories and feeders. They are followed in a few days or weeks by the females. These amazing creatures flap their wings 15-80 times a second, can hover in mid-air and are the only birds able to fly backward. They have a very high metabolism with a heart rate of 1,260 beats per minute and fly at tree-top level 20 to 60 miles a day.

Many people are excited about their return but none more than Campbell. Each Wednesday morning she captures and bands hummingbirds, and throughout the season she invites the public to observe her performing her job.

Campbell catches the birds, gives them a drink, measures their wings, tail and bill, and weighs them. She also determines if they are male or female.

"Determining the sex is fairly simple," Campbell says. "If they are mature birds, they have a different coloration. The male has a ruby throat, thus the name. On young birds that have not gotten their adult feathers, the sex can be determined by the wing feathers. Male and females have a different feather structure. This difference causes the sound of the wing beat to be different, and it is believed that the birds can identify males from females by their flying sound alone although they have very keen eyesight."

Campbell notes that there are more males than females in the spring.

"Males are smaller and more curious and consequently have a higher mortality rate," she says. "We believe that starting out with more males is nature's way of preserving the species."

Until several years ago not much was known about hummingbirds. It is through the efforts of Campbell and others like her that so much has been learned by the gathering of data. Before Campbell releases the birds, she marks them with a white dot on the head. These marked birds can be tracked to see where they go and how long they live, giving researchers more data about these remarkable creatures.

Visit www.hummingbirds.net for more details on these little creatures.

Campbell conducts public banding demonstrations every Wednesday morning at Weymouth Woods Sandhills Nature Preserve at the visitors' center mid-April through mid-September. She suggests calling 692-2167 for more details.

Dolores Muller is a local freelance writer.