NEWBURYPORT, Mass (Reuters Life!) - On a recent frigid morning, winds howling in from the west, David Weaver peered through binoculars over the Merrimack River in Massachusetts, scanning for an icon: the American bald eagle.
Haliaeetus leucocephalus, America’s national bird, is frequently seen in winter in the Joppa Flats area, where the Merrimack widens and meets the churning Atlantic Ocean after a brisk, 110-mile (177-km) journey from Franklin, New Hampshire.
Frozen water upstream pushes the birds toward the coast in search of food. Two pairs also nest in the area, where their eggs typically hatch in late April.
“There’s no greater thrill for me than to get somebody behind a telescope with an eagle in it,” said Weaver, 71, a retired wildlife biologist.
Some 2,000 visitors, a record, attended the fifth annual Merrimack River Eagle Festival in February at Mass Audubon’s Joppa Flats Education Center and its friendly rival, the Parker River National Wildlife Center.
The festival owes its existence to the 34 years that the birds spent on the federal Endangered Species List.
Bald eagles, which appear on the Seal of the President of the United States, became one of only a handful of species to fight back from the verge of extinction.
The giant birds of prey, with a wingspan of up to eight feet, are found throughout most of North America, from Alaska and Canada to northern Mexico.
In Massachusetts, a statewide census in the past year found 71 bald eagles, including 25 young birds, compared with just eight total counted in 1980.
Before Europeans first settled in North America the species may have numbered half a million. Their decline was centuries long and almost total.
“They have no predators other than man,” Weaver said.
More than 100,000 bald eagles were killed in Alaska alone from 1917 to 1953, where salmon fishermen feared they were a threat to the fish population.
Later in the 20th century, chemicals proved the great birds’ undoing. The pesticide DDT was sprayed on plants, eaten by small animals and consumed in higher concentration by eagles, perched at the top of the food chain.
DDT harmed adult birds and their eggs. Many egg shells became too thin to survive incubation. Bald eagles, a species where at the best of times 90 percent of birds don’t make it to adulthood, were on the brink.
The 1972 U.S. ban on DDT kick-started the eagles’ comeback. As public awareness of the species’ perilous situation increased, many states placed bald eagles on their lists of endangered species in the 1960s and early 1970s. The Endangered Species Act became national law in 1973.
With eagle numbers substantially revived, the Interior Department took the birds off the list in 2007. Bald eagles are still protected by the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act.
Although eagle numbers are up overall, bird-spotters are not always in luck. A few days of thaw has freed up the Merrimack’s flow, and the huge birds are absent this morning at each of their usual locations.
Another enthusiast, Ganson “Jock” Purcell, 73, summed up the ephemeral nature of wildlife spotting.
Surveying the scene from the deck of his home perched over the river, the retired obstetrician said: “You should have been here yesterday. It was great.”
Editing by Eric Beech