Earlier this year, the U.S. Fish and Wildlife Service announced what it called a milestone for the California condor: More chicks had hatched and fledged in the wild during 2015 than the number of condors that had died. In late March, Steve Kirkland, the agency’s condor field coordinator, reported that two more chicks had fledged in 2015 in Baja California, but had only just been discovered, bringing the total in the wild to 270.
It was perhaps the most promising news about the condor in decades.
The odds of restoring the California condor have looked chancy for years, and not just because its numbers reached a perilously low 22 before every last one was rounded up in 1982 for a captive breeding program. The bird with a wingspan of nearly 10 feet once glided over much of North America. But that range shrank to the West Coast and portions of the Southwest about 10,000 years ago, when the late Pleistocene animals whose carcasses it fed on went extinct. During the 20th century, poaching, habitat loss, and lead poisoning reduced the vulture’s population to fewer than two-dozen.
The U.S. government’s response — rounding up the birds for a last-ditch captive breeding program, then slowly releasing newly bred birds to the wild — deeply divided conservationists. Some thought the condors wouldn’t breed successfully. Others felt taking the birds out of the wild would only encourage more development of open areas within their range. Still others feared the birds would become a pallid, tame version of their wild selves.
Condors’ release back to the wild over the past two and a half decades has been fraught with peril. They have been electrocuted by power lines, poisoned by lead, and are too chummy by half with people. They have an unfortunate attraction to the detritus of human civilization, downing shiny objects like bottle caps and drinking from puddles of bright-green antifreeze. They are fed proffered carcasses to protect them from ingesting lead ammunition, and are captured for monitoring and, when necessary, chelation — using another substance to bind with the lead so that it is removed by the body. As recently as 2012, a research paper in the journal PNAS titled “ Lead poisoning and the deceptive recovery of the California condor” concluded that any successes should be chalked up to better condor management, not to a true resurgence of the carrion eaters.
That ongoing dependence on humans has certainly been an issue in condor recovery, but a report this year in the journal EcoHealth noted encouraging signs. As the flock increased — mainly through releases from the captive breeding program — the birds expanded their range. They were more likely to engage in wild behaviors. They were foraging for their own food. Some were harder to capture for monitoring, a promising indicator of skittishness around people. There hasn’t been a confirmed electrocution since 2004, according to the U.S. Fish and Wildlife Service, indicating that not only did power-pole aversion training in captivity work, but it is being transmitted to wild-born condors.
But for all this good news, lead remains an intractable obstacle.
The condor is North America’s largest land bird; its stunning wingspan allows it to soar for miles, without flapping its wings, over its range, which includes a huge U-shaped expanse of mountainous land in California, as well as the Grand Canyon area and a small section of Baja California. Its natural lifespan is long, too — 60 years. Its feathering is almost entirely black, with the typical carrion eater’s bald head, useful for feeding off carcasses — too many of which are tainted by lead ammunition, particularly as the birds increasingly forage for themselves. The primary source of lead in condors, studies have found, is from ingesting ammunition that remains in the carcasses of animals that have been shot. As lead builds up in the bloodstream, it can damage the birds’ organs and nervous systems.
According to Myra Finkelstein, a UC Santa Cruz researcher who was co-author of both the PNAS and EcoHealth studies, the birds feed off 75 to 100 carcasses a year. Over their lifetime, “that’s a lot of opportunity to ingest lead,” she said.
Arizona and Utah have voluntary bans on lead ammunition; surveys indicate that up to 90% of hunters comply, but that might not be good enough. California is phasing in a lead-ammunition ban; by 2019, it will be illegal to kill any animal, whether a deer or a diseased steer, with lead bullets or shot. Copper bullets are cheaper and more accurate than ever.
But monitoring lead — or getting a firm grip on the number of condors — could prove tougher as more of the birds resist capture. “We might have to guess more at the population numbers instead of having a precise census,” Kirkland said after the recent discovery of two chicks. Lead levels were down on average in the 100 or so birds that were monitored last year, which could be a good sign, Kirkland said, or a blip, or an indication that the more tainted birds couldn’t be caught.
Without near-elimination of lead ammunition, a full turnaround for the bird is unlikely, Finkelstein said. But in every other way, the condor might be poised to fly on its own.