It’s hard to imagine a more iconic symbol of the United States of America than the bald eagle. Many Native American peoples have long considered the bird sacred, cherishing its feathers for ceremonial and spiritual purposes. The eagle has also signified strength and freedom since it was added to the Great Seal of the United States in 1782.
Yet Haliaeetus leucocephalus nearly disappeared from the lower 48 states – more than once, says Andrew Mergen, faculty director of the Emmett Environmental Law and Policy Clinic at Harvard Law School.
“The bald eagle almost went extinct twice, and it almost went extinct twice for different reasons,” says Mergen, who is also the Emmett Assistant Clinical Professor of Environmental Law at Harvard – and an avid birdwatcher.
That the bald eagle not only survives – but thrives – across the U.S. today is a testament to the work of brave lawyers, advocates, and Native activists over a century of the environmental movement, Mergen argues.
“The story of the eagle is a story of environmental law working,” he says.
A ‘bird of bad moral character’
Mergen says that non-Indigenous Americans weren’t always enamored of the bald eagle, despite its symbolic significance. (Benjamin Franklin famously derided it as a “bird of bad moral character,” which “does not get his living honestly.”)
Like Franklin, many Americans considered the bird a nuisance or even a threat, much as some in the modern era view coyotes and wolves, says Mergen.
“The mindset was that anything that preys on other things, and especially anything that might prey on things that are useful to us, are bad animals,” he says. “There was this idea that they were inherently in conflict with people.”
Americans hunted the bald eagle for sport or out of antipathy, which caused the animal’s population to plummet by the early 20th century. The eagle was not alone – declines occurred among other bird species, too, which were harvested for food, fashion, and collecting.
Yet this period also marked the dawn of the environmental movement, even if many of these advocates prioritized resource management and game conservation for less-than-noble reasons, Mergen says: “One of the arguments for limiting hunting of migratory birds was that we should save animals like waterfowl for gentlemen hunters and not let people shoot birds indiscriminately.”
Whatever their motives, these activists pressed the government for national change. It wouldn’t come easy: an early law prohibiting the killing of migratory birds was shot down as unconstitutional in federal court, Mergen says.
“We had a narrower conception of the Commerce Clause than we have today,” he says, referring to the constitutional provision granting Congress the power to regulate interstate commerce. “The court said that dealing with wildlife is the business of the states, and that the federal government had no role in it.”
But the advocates were not cowed – instead, they got creative with the law, Mergen says.
“They came up with a new strategy – Congress would enter into a treaty with Great Britain to preserve migratory birds,” he says. “And then they would pass a new law protecting the birds as part of enforcement of that treaty.”
In a landmark Supreme Court decision from 1920, Justice Oliver Wendell Holmes Jr. LL.B. 1866 upheld that law – the Migratory Bird Treaty Act – and even praised the ambition behind it.
“He wrote that Congress not only has the power to do this, but that this is an act of conservation of immense importance – that we should save our birds,” Mergen says.
A renaissance, then a new threat
In the wake of the decision, environmentalists such as Rosalie Edge pushed for enforcement, focusing particularly on raptors, including bald eagles. Her life’s work, which eventually included the establishment of a sanctuary in Pennsylvania dedicated to birds of prey, helped break down the American public’s distinction between so-called “good birds,” such as songbirds and those that eat insects, and “bad birds,” Mergen says.
“As a culture, we were beginning to admire the bald eagle,” he says. “We were beginning to think about how it is our national symbol, and we shouldn’t kill them.”
That shift in the public’s attitude is reflected in Congress’s passage of the Eagle Protection Act of 1940, which granted additional protections, Mergen says. “World War II is going on. People are focused on symbols of patriotism, and they’re increasingly aware of the risks that bald eagles are facing.”
Yet ironically, even as Americans’ interest in protecting their national bird was growing, the bald eagle faced its most dire threat yet – the pesticide DDT. Used widely as an insecticide in the postwar years, DDT made its way into ecosystems and eventually eagles’ bodies, causing them to lay eggs with shells too thin and brittle to hatch.
Once again, the risk was existential, Mergen says: By 1963, just 417 nesting pairs remained in the contiguous United States.
Rachel Carson’s groundbreaking book, “Silent Spring,” which exposed the harms caused by pesticides such as DDT, arrived at just the right moment, Mergen argues.
“In my opinion, she’s one of the greatest environmental thinkers who ever lived,” Mergen says. “When she goes after the pesticide companies, they come after her very hard. They totally smear her.”
But it was too late – Carson and her contemporaries had already begun to change the narrative, Mergen says, demonstrating how deeply human concerns are intertwined with the natural world and sparking a broader interest in environmental protection.
“All these things are happening. The Cuyahoga River in Ohio is on fire; there’s a huge oil spill off the coast of Santa Barbara. People are starting to become aware,” Mergen says.
A Harvard Law alumnus and a ‘very bold stance’
The burgeoning movement cut across political lines. In 1970, President Richard Nixon created the Environmental Protection Agency, and in 1973, he signed the modern Endangered Species Act. Nixon also signed laws protecting the nation’s air and water.
Each of these efforts built on previous protections for the bald eagle and played a role in the bird’s recovery, Mergen says. Being listed as endangered and threatened under the Endangered Species Act meant safeguarding more of the bird’s habitat, as well as support for breeding programs to reintroduce the eagle to areas from which it had disappeared.
But the thing that really saved the bald eagle, Mergen argues, was the EPA’s ban on DDT.
And that came down to William Ruckelshaus LL.B. ’60, a Harvard Law School-trained lawyer, moderate Republican, and the inaugural head of the EPA.
“He decides to take the very bold stance to prohibit the use of DDT, even though he faces a lot of industry pressure against him. It is one of the many brave, principled things he does in his life,” Mergen says. (Ruckelshaus would later serve as Nixon’s Deputy Attorney General, resigning in 1973 during what is known as the “Saturday Night Massacre,” after refusing to fire the independent special prosecutor investigating Watergate.)
The DDT ban paid off, Mergen says. “The birds come back – not all at once, but slowly, they do come back.”
Today, the American Eagle Foundation estimates that there are more than 71,000 nesting pairs in the lower 48 states, and tens of thousands more in Alaska. “They’ve made an extraordinary recovery,” Mergen says.
The bald eagle’s comeback has been so remarkable, in fact, that it was removed from the endangered species list in 2007.
Not to worry, Mergen says. “The bird still has a lot of protections under the Bald and Golden Eagle Protection Act. One issue today is wind development, because of the risk the turbines pose to eagles and their habitat, but those risks can be mitigated with careful planning.”
He argues that the bald eagle’s success story mirrors the evolution of American environmental law over the last century – from an early emphasis on preventing direct harms such as hunting and poaching, toward a more complex approach that addresses downstream ecological impacts of human activity, including pollution and habitat disruption.
“As Carson showed, it’s all connected,” he says. “We live in a complicated world. If we want to preserve nature, it will require mindfulness and attention that we are not always very good at as a species.”
And thanks to people like Edge, Carson, Ruckelshaus, and many others, Mergen believes the story also demonstrates the power of bold action – and integrity. “There are a lot of people doing the right thing here. It’s an important story for today.”
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