NASHVILLE, Tenn. - On Dec. 28, 1973, President Richard Nixon signed the Endangered Species Act. “Nothing,” he said, “is more priceless and more worthy of preservation than the rich array of animal life with which our country has been blessed.” The powerful new law charged the federal government with saving every endangered plant and animal in America and enjoyed nearly unanimous bipartisan support.

The Act was so sweeping that, in retrospect, it was bound to become controversial, especially since it allowed species to be listed as endangered without consideration for the economic consequences. In that way it pitted two American values against each other: the idea that Americans should preserve their incredible natural resources (the United States invented the national park, after all) and the notion that capitalism was king and private property inviolate.

The Endangered Species Act was just one in a raft of environmental legislation passed beginning in the mid-1960s that included the Clean Water Act, the Clean Air Act, the Wilderness Act and the National Wild and Scenic Rivers Act. Taken together, it was the most extensive environmental legislation the world had ever seen.

The United States’ own national animals, the bison and the bald eagle, had been driven to near extinction. When they started to recover, Americans saw the Endangered Species Act as a success. But when animals that people had never heard of began interfering with development, it was a different story.

Left to navigate this minefield was a group of young biologists in Washington - the first Office of Endangered Species.

The Snail Darter

Ichthyologist Jim Williams, the Office of Endangered Species’ first “fish guy,” was hired in 1974, just as things were getting up and running. Williams describes his cohort as “a bunch of conservation-minded biologists that were all on a mission to save every last one of our chosen group of organisms come hell or high water, and, by the way, to hell with the bureaucrats and politicians.”

His unconventional attitude and methods soon became apparent with the listing of the snail darter, a little fish now so notorious it has become synonymous with government overreach. At the time, it had just been discovered and was only known to exist in one stretch of the Little Tennessee River - which the Tennessee Valley Authority was planning to dam.

“I started talking about listing it, and boy, oh boy, did the crap hit the fan,” Williams says. He said the associate director “called me in one day and said, ‘You’re going to cost us the whole damn Act. They’re going to just throw this thing out when you try to list this thing. You can’t do this.’ And I said, ‘Hey, I’m calling them like I see them.’”

Williams did list the snail darter. The Act survived. But it would never again enjoy the support of its earliest days. Whether the government should try to save all species from extinction, or if not, where to draw the line, became a point of conflict that has never been fully resolved.

At one point, administrators implemented a priority system for what animals should be listed. “And literally it would change almost from week to week,” Williams says.

‘Save Ken Dodd and rattlesnakes’

Ken Dodd is a herpetologist who was recruited to the Office of Endangered Species in 1976 for a 30-day appointment that turned into eight years.

“There was not a whole lot of conservation theory at the time to draw on,” he says. “So we were really at the cutting edge of determining what is necessary for conservation. ... So we were - I’m not saying winging it - we were deeply into what an endangered species is, how it is to be determined.”

Like Williams, Dodd regularly butted heads with administrators. He also followed the science where it led without thought for whom it might inconvenience. That included going up against the Purina pet food company (successfully) and Monsanto (not so much).

A man named Dominique D’Ermo owned a Washington restaurant that was serving rattlesnake meat he said was from Pennsylvania. That would have violated a law called the Lacey Act. “So I wrote to the restaurant and said, ‘Hey, Dominique, I think you need to get a better source,’” Dodd says.

It turned out Interior Secretary Cecil Andrus was a regular patron of the restaurant. When he learned what Dodd had done, “He fired me - which did not go over real well. ...You can’t just fire a federal employee, you know, just because you don’t like what they did.”

Dodd hired an attorney. Meanwhile, according to Williams, “We all went down to a T-shirt shop, got shirts that said ‘Save Ken Dodd and Rattlesnakes’.”

The ensuing publicity made an impact. Soon, Dodd was back at work.

Gray wolf season

Ron Nowak joined the office in 1973 after working on surveys of wolves and panthers. The animals he was responsible for were often furry and charismatic, more relatable for most people than a fish or salamander. But Nowak would not suffer fools, which is how he ended up, in the mid-1980s, testifying against his own agency.

In northern Minnesota, the gray wolf was coming back from “just a tiny remnant of a couple hundred animals to maybe several hundred or a thousand” thanks to the Endangered Species Act.

“And so what did the Fish and Wildlife Service want to do? They wanted to cooperate with the state of Minnesota and open the gray wolf to public hunting.”

That would require a regulation showing that a hunting season would benefit the wolves and was the only way to control their population.

“They told me, ‘You have to write the regulation,’” Nowak says. “And I said, ‘It would be illegal.’”

The Fish and Wildlife Service found someone else to write the regulation. Conservation groups sued, calling Nowak as a witness.

He went out to Minnesota and gave depositions saying the wolves should not have been open to hunting.

The conservation groups won. The government appealed. The conservation groups won again.

The California Condor

LaVerne Smith was hired in 1978 as one of the Office of Endangered Species’ first botanists. Unlike many of her colleagues, she continued to work in the endangered species program for most of her career, through many office reorganizations.

That included a 1987 shuffle that moved the responsibility for listing species to regional offices - a reorg controversial enough that it prompted a eulogy of sorts in The New York Times.

“The Office of Endangered Species has gone the way of the dusky seaside sparrow and the Sampson’s pearly mussel,” the story read. “Like six of the species that it was created to protect in 1973, it has become extinct.”

One of the early decisions involved the critically endangered California condor, whose numbers had dwindled to 23 by 1982. Biologists debated if they should they watch the condors go extinct or bring those final birds into captivity and try to breed them. If they did, what would be the likelihood of success?

High, it turned out. “They’re out sailing around in California again. They’re out sailing around the Grand Canyon. And I think anyone who’s seen one - the day I saw one sail over the Grand Canyon, I was like, ‘Oh my God! That was all worth it.’”

Smith later transferred to Alaska, where she led the listing for the polar bear, the first animal to be listed as endangered because of climate change.