Strong conservation efforts leads to resurgence of bald eagles in Rhode Island
By ecoRI News staff
The past year has been a record year for an American icon in the Ocean State. According to the Audubon Society of Rhode Island, bald eagles have been spotted soaring above the Seekonk River in Providence and perched in trees along the Blackstone River Bikeway in Cumberland.
From the shoreline in Newport, to Coventry and locations across South County, there have been numerous eagle sightings reported throughout the state, according to the nonprofit. Until quite recently, these large raptors teetered on the brink of extinction. They hadn’t been seen in Rhode Island until the past decade.
Long road back
“Here’s a bird with an immense distribution across the country when we virtually extirpated it,” said ornithologist and Audubon board member Charles Clarkson. “We’re just now starting to pull ourselves back from that situation.”
He said it’s a misconception that bald and golden eagles declined mostly from the use of the pesticide DDT. “While it played a rather important role, there’s much more to it than that,” he said.
Clarkson said there were about 100,000 eagles across America in the 1700s. That number went into decline soon after, because of habitat degradation and a developing salmon fishing industry. The great forests that dominated the American landscape vanished as the young country grew.
“Habitat loss has been a precursor to every species decline on earth,” Clarkson said. “Loss of resources and actual aggressive degradation of food sources, through DDT and lead poisoning from eagles feeding on carcasses of animals that contained lead from bird shot, did further damage. The insults came from multiple directions.”
Some of the mainstays of the eagle diet, such as shore birds and ducks, began to dwindle because of overhunting. Then there was also another factor that, by today’s standards, seems unthinkable: hunting.
“We had allowed farmers and fishermen to hunt these animals,” Clarkson said.
According to U.S. Fish & Wildlife, the eagle population dropped to an all-time low of 417 nesting pairs in 1963, even after several laws were enacted to protect the eagle, such as the Migratory Bird Treaty Act of 1936.
The use of DDT remained common until 1972, when the federal government banned it. In 1973, arguably the single most important element in eagle recovery became a law: the Endangered Species Act. Not only did the act protect raptors against hunting, it also reduced the threats to eagle habitat, including nesting sites and summer and winter roost sites.
Habitat protection, eagle restoration and monitoring combined to bring bald and golden eagles to the point where the population, now climbing to an estimated 9,789 breeding pairs, was delisted in 2007.
Choosing a nesting site
Eagle nests may be up to 10 feet across and, according to Fish & Wildlife, weigh up to 4,000 pounds. The birds, which mate for life, tend to return to the same sight year after year. The life expectancy of an eagle in the wild is roughly 30 years.
“Juvenile sightings are a good thing year-round,” Clarkson said. “They have no mate; they’re just exploring the territory. It’s good that these birds are exploring for long distances. That helps in maintaining genetic diversity.”
Eagles prefer freshwater nesting sites, and are more prey specific during mating season, but they become generalists in the off-season, according to Clarkson.
It’s difficult to tell where the juveniles in Rhode Island originated from, Clarkson said. Maine has the largest nesting population of bald eagles in New England, but Virginia also has a large population, and eagles are more than capable of covering either distance to get to the Ocean State.
“Having these birds breed in state would be a real bonus in terms of the condition of the habitat,” Clarkson said. “It would mean that we’ve conserved the habitat well. They tend to shy away from fragmented habitat. They may approach (potential nesting) areas from three to four thousand feet and then they assess the nesting conditions from up there.”
There was a nesting site in Scituate from roughly 2003 to 2007, and there are three, possibly four current sites in the state, he said, but it remains to be seen how many eagles will choose to remain in Rhode Island.