TEHACHAPI, Calif. (CBS News) — The California condor is the largest flying land bird in North America. What it lacks in looks it makes up for in majesty. Its nine-and-a-half-foot wingspan leaves quite an impression if you’re lucky enough to ever see one.

Or 20.

Last May in Tehachapi Cinda Michols came home to discover that 15 to 20 condors had descended on her home. Such a scene would have been unthinkable just three decades ago. Back then, there wasn’t a single California condor left in the wild.

In the late 1980s, the last few California condors in existence were brought into captivity to save the species from extinction. Since then, the vultures have been bred and slowly reintroduced into the wild. There are now more than 500 total — a number that’s small enough that biologists still number them all.

Chris Parish, the director of global conservation at the Peregrine Fund, showed correspondent Conor Knighton a white board of “retired” numbers: “They’re all here for a reason and this is not a place you want your number because these are birds that have passed.”

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A female condor in Zion National Park, Utah in 2019. (National Park Service via AP)

While the reappearance of condors in our skies is certainly a success story, the endangered birds are still struggling. Researchers eventually learned why. According to Parish, “Fifty-four percent of all death in our population that we monitor that intensively is lead poisoning.”

Lead is a dangerous neurotoxin. It’s also what most ammunition is made out of. The birds are dying from bullets. They’re not getting shot by them; they’re literally eating lead.

“Scavenging wildlife that are obligates like the condor — they only consume things that are already dead,” Parish said.

Here’s the problem: When hunters kill an animal like a deer they often leave behind some of the remains. But they may be unintentionally leaving behind tiny fragments of lead, which ends up in the condors when they swing by to enjoy a meal.

“Some of those tiny fragments that strip off of those bullets we’ve used for 100 years can poison wildlife,” Parish said.

In Marble Canyon, Ariz., Parish’s team traps and tests condors. Most have detectable lead levels so they treat the birds then release them once they’re healthy.

Knighton asked, “Right now, you trap them, you test them, you treat them, you release them but it seems like that will just keep happening again and again, unless the ammunition changes?”

“We’re in a holding pattern,” Parish replied. “We’ve come to a real fine understanding of what the problem is and we know how to solve it. Now, we have to go solve it.”

But solving this can feel like a long shot.

Parish is on a mission to convince hunters to hunt with non-lead ammunition, like copper bullets, doing demonstrations across the country. It’s a world he knows well: “I’m kind of a redneck hunter-biologist and these hunters are my people.”

Unfortunately, copper ammunition is generally more expensive, is harder to find and is just not what people are used to.

“Changing tradition is hard,” Parish said. “It’s not as simple as, ‘Here’s the science, here’s the logic so do the right thing.’ We don’t live in that era anymore, you know? And people who sell products are very effective at marketing. People who work in conservation, we’re not really good at marketing!”

In 2019, California instituted a statewide ban on lead ammunition for hunting but the California condor is also found in Utah and Arizona, states where there aren’t bans.

Parish doesn’t believe a legislative solution is the answer: “We have a speed limit but people break that law, too. And I’m not saying the hunters are a bunch of bad actors; I’m just saying if they don’t understand it, they might well write it off as a piece of unnecessary legislation that really isn’t a problem.”

“It seems like a very difficult law to enforce when you’re out in the woods,” Knighton noted.

“It’s almost impossible.”

Instead, Parish favors a voluntary approach. He co-founded the North American Non-Lead Partnership to reach out to hunters. So far, the response has been encouraging: An estimated 90 percent of deer hunters on Arizona’s Kaibab Plateau now hunt with non-lead or pack out all remains.

“We know that hunters are the only ones that can solve this problem,” said Parish. “So, by pointing to them and saying, ‘You’re doing a bad thing,’ that’s not gonna work. You need to appeal to their conservation ethic and their history of conservation in saying, ‘Here’s yet another opportunity where we as hunters can leave a healthier environment for all of the critters that live in it, not just those that we hunt, for future generations to enjoy.'”

One day, Parish hopes hunters across the country will shoot with alternative ammunition to protect all scavenging animals. Until then, he’ll keep getting the word out to help get the lead out.

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