The one-two punch that Mother Nature dropped on Maine this April appears to have taken a heavy toll on the state’s youngest bald eagles, according to biologists still surveying damage from the fierce storms.
The heavy snowfall and near hurricane-force winds demolished nests, knocked down trees and overpowered adult eagles’ ability to protect their fragile eggs or hatchlings from the elements.
Damage is most severe on the coast, where at least a dozen destroyed nests have been identified so far.
The good news, biologists said, is that this year’s higher eaglet mortality rates should show up as a temporary – albeit disappointing – blip amid the eagle’s strong recovery in Maine.
“With so many eagles in the state, this is not doom and gloom but more a bump in the road,” said Charlie Todd, the Maine Department of Inland Fisheries and Wildlife’s lead eagle biologist. “Fortunately, we have over 400 pairs instead of 40-something, and they can withstand that.”
Maine had at least 414 breeding pairs of eagles last year. That is more than the breeding populations in all other New England states plus New York, Pennsylvania, New Jersey and Delaware combined.
On the entire East Coast, only Virginia and Florida boast higher numbers of reproducing eagles.
Eagles in Maine typically lay one to three eggs, which will often hatch in early April after several weeks of incubation. During the initial weeks the eaglets are tiny, down-covered fuzz balls that need constant feeding, not to mention protection from cold, wind and precipitation.
So the significant snowstorm and nor’easter that slammed into the state during the first few weeks of April came at a particularly bad time for the hatchlings, said Wing Goodale, a research biologist with the BioDiversity Research Institute in Gorham.
“These little guys have a little bit of fat reserves from the egg, but that’s about it,” Goodale said. “They just don’t have the protective fat layers and feathers to keep them as warm and dry as they need to be.”
Goodale’s organization caught some of this life-and-death struggle live on a Webcam placed next to an eagle nest in coastal Hancock County. Webcam viewers watched as the two adults tried to pin themselves down on the nest on top of the hatchlings to keep them warm and block the blinding rain.
But with wind gusts approaching hurricane strength, the adults could do only so much.
“My speculation is the chicks died of exposure,” Goodale said.
That scene was likely repeated throughout Maine. Two days after the first big snowstorm of the month, Todd said he conducted a fly-over of nests and saw at least nine where eagles had apparently been forced to abandon any eggs or young.
At least a dozen of the 30 nests that Todd and other biologists surveyed between Harpswell and Eastport were destroyed during the nor’easter. While Todd believes those figures are likely disproportionately high, he knows other trees or nests were likely damaged.
The storms even claimed one of Maine’s best known and most historic nests.
For the past 49 years, several generations of eagles have nested in a tree on the shores of Damariscotta Lake in Waldo County. It predates the eagle population collapse of the 1960s and 1970s that prompted the federal government to place the birds under additional protection.
Eagles that lose a nest will either try to find another suitable existing nest – occasionally by stealing it from other eagles or ospreys – or begin to build a new one.
But with many existing nests measuring 6 feet across and weighing up to 1,000 pounds, building a new suitable home is no quick or easy task, Todd said.
While some eagles that lose a hatch will attempt to breed again, many pairs will have to wait until next year.
Maine’s eagle population has been growing by about 8 percent annually for the past 20-some years, thanks in large part to eagles’ long reproductive life.
Eagles reach sexual maturity – and develop their characteristic white head and tail – at age 5 and can live into their upper 20s. Many pairs will mate in the same nest for 15 years or longer.
Today there are an estimated 9,789 breeding pairs of eagles in the lower 48 states.
But in 1963, there were just 417 breeding pairs of eagles in the continental U.S. Widespread use of the pesticide DDT after World War II had decimated eagle populations and had them hurtling toward extinction.
But the tide began shifting back in the eagles’ favor when Rachel Carson, the late U.S. Fish and Wildlife Service biologist who worked at times in Maine, published her book “Silent Spring” in 1962.
The book, which is often regarded as the spark that ignited the modern environmental movement, chronicled the dangers of DDT and other pesticides to humans and wildlife.
Although vilified by the chemical and agricultural industry, “Silent Spring” helped bring about a ban on DDT and protections for eagles and other wildlife.
Biologists and conservationists are citing the eagle’s recovery as one of Carson’s lasting legacies as they celebrate the 100th anniversary of her birth this May 27.
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