Not that long ago, most people may have considering a bald eagle sighting a once-in-a-lifetime thrill.

On this Fourth of July, seeing our national bird in flight remains a thrill, but one even casual outdoors enthusiasts in the Valley are enjoying with increasing frequency.

An eagle’s nest has been established for several years at a spot along the Susquehanna River between Sunbury and Danville. Newer nesting spots were spotted last year, including a nest on Byer’s Island in the Susquehanna River, off Hummels Wharf and another on Cat Bird Island in the North Branch of the Susquehanna, near Winfield.

The day of the Audubon Society’s Christmas bird count, past president Allen Schweinberg did not have to travel far to add an eagle to his tally — one flew past a window of his home near Lewisburg. It was the first time he’d ever seen an eagle in his yard. It has been far from the only time he has seen one of the majestic birds. Schweinsberg’s discovery of the nest on Cat Bird Island was the first documented viewing of an eagle nest on the North Branch of the river.

The resurgence of the bald eagle in the Central Susquehanna Valley mirrors the success of restoration efforts statewide.

Presently, there are at least 170 known nests, including 36 new nests statewide. Also, for the first time in the agency’s annual survey, Clinton and Mifflin counties were added to the list of counties hosting bald eagle nests. In June of 2008, Game Commission biologists estimated Pennsylvania had 140 known nests in 47 counties. The final nest count turned out to be 156.

Eagles’ diet consists largely of fish, so the birds will mainly stay along the river, but the eagles from the Cat Bird Island nest have been spotted by people on the Lewisburg bridge, about 4-5 miles upstream, Schweinsberg said.

“With the banning of DDT in 1972, as well as the ensuing environmental clean up efforts launched in the 1970s, the stage was set for bald eagles to recover on their own,” state Game Commission Executive Director Carl G. Roe said in a written statement. “However, there is no doubt that the Game Commission’s reintroduction efforts from 1983 through 1989 helped the bald eagle population grow exponentially, from just three known nests in Crawford County in 1983, to nearly 180 nests in 49 of the state’s 67 counties this year.“

As recently as 1983, there were only three eagle nests remaining in Pennsylvania. That year, the Game Commission began a seven-year bald eagle reintroduction program in which the agency sent employees to Saskatchewan to obtain eaglets from wilderness nests. The Richard King Mellon Foundation of Pittsburgh and the federal Endangered Species Fund provided financial assistance for this effort. In all, 88 Canadian bald eagles were released from sites located at Dauphin County’s Haldeman Island and Pike County’s Shohola Falls.

Since 1983, Pennsylvania’s eagle nests have produced more than 1,200 eaglets, and the population has increased by about 15 percent annually.

With the success of the eagle restoration, bird-watching enthusiasts note that the Central Susquehanna Valley has become the home of even rarer birds. Schweinsberg said there are Peregrine falcons nesting on a cliff along the Shikellamy State Park Overlook.

Statewide, there are only about 20 known Peregrine falcon nests, including just two or three that are located on cliffs.