Washington is a city where cameras keep an eye out, 24/7, for shoplifters, illegal drivers and potential terrorists. A new one joined the lineup yesterday, but with another purpose: Anyone with a computer and Internet connection can watch a nest of ospreys on the Anacostia River.

The nest, which looks like a huge pile of sticks, is on a pier under the Frederick Douglass Bridge and is occupied by two chicks and their parents, who make periodic forays to catch fish for the chicks. The nest has been used for several months in the spring and summer for about a dozen years.

The "nestcam" is the culmination of an education and video project about birds of prey involving students from Neval Thomas Elementary School in Northeast Washington and the Earth Conservation Corps, an environmental group. It was turned on at the end of a signing ceremony for a federal-city agreement to cooperate in replacing the 55-year-old bridge, a goal that's been talked about for a decade and may take years more to achieve.

The weatherproof camera was installed Monday -- very carefully -- on a pole a few feet from the nest. There are three other osprey nests on piers under the bridge. The hawks seem to be oblivious to the rumbling of vehicle traffic and the frequent thundering of helicopters above them.

The camera taps into a growing trend that puts wildlife at people's fingertips, via the Internet, in hopes that by entertaining people, it will encourage them to become environmental advocates. Right now, "webcams" make it possible to watch a nesting Pacific loon in Alaska, storks with chicks in Germany and bald eagles in Washington state, among others.

"This camera will let us observe round-the-clock ospreys," Byron Smith, an 11-year-old fifth-grader, told the politicians, reporters and others assembled for the event at the environmental group's headquarters in Southeast Washington, within sight of the bridge across South Capitol Street.

Inside, Mayor Anthony A. Williams (D) flipped the switch -- or, rather, hit a laptop's "enter" key -- to turn on the camera. Byron showed him how to zoom in and out. Williams, a longtime birder, told Byron and other students gathered around that ospreys are among his favorites.

"The osprey is picked on by eagles," Williams said. "The osprey catches the fish and the eagles grab it."

The mayor intended no political allegory. He told the students that he empathized with the osprey because he was the second child in his family, with an older brother who "picked on me."

Yesterday's event will be featured in a documentary about the student project that will be shown on D.C. cable television. The National Geographic Education Foundation, which funded the project, also plans to distribute the documentary and curriculum material to 2 million schoolchildren throughout the country.

The two osprey chicks are probably about 21/2 weeks old, said U.S. Fish and Wildlife Service biologist Craig Koppie. Within a month, their parents, which have the distinctive white heads and brown bodies of adult birds, will try to coax them out of the nest with food. By August, the nest will be empty, because the chicks will be full-fledged and able to join other ospreys that congregate in September for the winter migration south, to Florida or Latin America. They return in February or March.

Birds of prey, such as eagles, hawks and falcons, are making a comeback in the Washington area, Koppie said. There is a pair of bald eagles in the District and another near the Wilson Bridge in Maryland. A peregrine pair is nesting on a highway bridge in the city, Koppie said, and he is certain a pair eventually will nest on the Douglass bridge.

Osprey, once declining in number largely because of DDT, began rebounding after the pesticide was banned three decades ago. They now are so common on rivers that some try to nest on people's sailboats, Koppie said.

Even if bridge construction disrupts the ospreys temporarily, he said, they will continue to make their home there.

The new bridge would not be as high as the existing one. To accommodate large vessels on the Anacostia River, it would have a movable span. It also would have sidewalks on both sides for pedestrians and bicyclists and a transit lane to allow light rail. Funding to begin the project is included in both House and Senate versions of a pending transportation bill, city officials said.

Planners envision the new bridge as a gateway to a revitalized Anacostia waterfront. Williams said it would be a piece of a grand project "making us one of the great waterfront cities of the world."

For her part, D.C. Council member Carol Schwartz (R-At Large) said, "Frederick Douglass -- I might add, a fine Republican -- is soon to have a fine monument."

"As far as I'm concerned," said Sen. James M. Jeffords (I-Vt.), standing behind microphones set up on a sunny riverside deck, "we need a lot more days like this."

The nestcam, at www.ecc1.org, was scheduled to be online by today. A Maryland osprey camera is at www.maryland.com/cam/ospreycam.php.