California condor: Saving North America’s biggest bird

California condors – known scientifically as Gymnogyps californianus – are imposing vultures. They’re the largest bird species in North America, with a massive wingspan of nearly three metres.

It’s hard to miss their long, sharp beaks. But rather than hunters, condors are scavengers. Gliding high above the ground, they use their keen eyesight to spot animal carcasses to eat.

A lack of safe sources of food was just one of the many reasons why, just a few decades ago, California condors came dangerously close to extinction. Conservationists have since been battling to save these impressive birds – but is our world ready for them to return to?

Plight of the condors

In the Pleistocene Epoch – 2.58 million to 11,700 years ago – several species of Gymnogyps vultures lived across North America. They soared through the skies from western Canada down to central Mexico, and as far east as Florida and New York.

Vultures are an important part of nature’s clean-up crew. Back then, these birds would have been kept well fed by the carcasses of North America’s megafauna. But when around 70% of these large animals went extinct towards the end of the epoch, it had a knock-on effect on scavenging birds.

With the Late Pleistocene extinction taking mastodons and mammoths off the menu, some experts think condors may have fallen back on eating washed-up marine mammal carcasses. 

By 1800, California condors – the only remaining member of their genus – were restricted to the westernmost parts of the continent. They mostly stuck to the Pacific coast, from near the mouth of the Columbia River – which sits on the border of Washington and Oregon – down to the mountainous inlands of Baja California in Mexico.

Around this time, the birds were likely sustained by the activities of European colonisers, switching from wild animals to the carcasses of livestock.

Starting in 1769, numerous Franciscan Missions were established along the Californian coast, from Sonoma down to San Diego. For decades, the hundreds of thousands of semi-feral cattle they and private ranchers kept were regularly slaughtered to fuel the hide and tallow trade. Scavengers, including vultures, usually claimed the abundant leftover carcasses.

But it didn’t last! The California hide trade started dwindling in the 1840s. As a consequence, livestock mortality decreased and condors’ dinner options started drying up again. At the same time, the rise of big game hunting limited their remaining wild food sources.

A growing interest in egg collecting added to their troubles as did the dramatic changes to their habitats. Land was increasingly being taken up with the building of new towns and the expansion of oil fields, while forest habitats were being impacted by the lumber trade. 

Controversial conservation

California condors were first protected in the USA in 1966 under the Endangered Species Preservation Act. By then only around 60 condors remained and they had retreated to California’s southern mountains.

The species continued to struggle and by 1982 there were only 22 individuals left. Drastic measures were needed to stop their nose-dive into extinction.

The California Condor Recovery Program began in 1979, led by the United States Fish and Wildlife Service (USFWS). Its goal is to re-establish a self-sustaining population of free-flying condors within their historic, natural range.

The team rested their hopes on a successful captive breeding programme. But choosing to round up wild condors for it was a controversial move. The plan soon became bogged down in legal and ethical opposition.

Despite the protests, given the difficulties the birds faced in their natural environment, a hands-on approach was ultimately seen as the birds’ best chance of survival. So, the captive breeding plan went ahead and what was left of the species was taken into captivity. 

When the individual Adult Condor 9 – or AC-9 for short – was captured in 1987, it meant that for the first time the California condor was extinct in the wild. Instead of flying free, the birds’ new homes were zoos, wildlife parks and other breeding facilities across North America.

A little over a year later, the breeding programme’s first captive condor chick hatched in San Diego. Named Moloko, the chick was a sign that the species had begun its long journey to recovery.

California condors can live for more than 60 years in the wild and only reach sexual maturity at six years old. They typically form long-term bonds with a single mate and spend most of their time together. Females lay a single egg, and the chick hatches after about eight weeks. They’re dedicated parents, caring for their chick in the nest until it’s six months old and takes its first flight. The juvenile tends to then stick with its parents for up to another year.  

Pairs of condors usually raise one chick every other year, but if they lose an egg at an early stage, such as to a predator, they can produce another in the same season. Conservationists found they could double-up on their breeding efforts by removing the first egg. By hand-rearing the first chick or giving it to an unpaired adult to foster, they could leave the original parents free to produce and care for a second egg.

In 2021, researchers also found that female California condors can have young without mating – an ability known as parthenogenesis. 

Free-flying condors

California condors were absent from North America’s skies for five years. Some were released in Southern California in 1992, but this wasn’t a great success.

Five of the 13 released condors died – one from kidney failure after drinking antifreeze and the other four from touching or colliding with power lines. The birds were also attracted to human-built structures and some even tried begging for food from people having picnics.

Condors are curious birds. They like exploring their environments but that can get them into trouble, such as entangling themselves in wires, and has earnt them a reputation for destruction.

Conservationists returned the surviving eight individuals to captivity in 1994 and reviewed their techniques before restarting releases in 1995. In 1996, a second release site was established at Vermilion Cliffs National Monument in Arizona. Big Sur in central California followed in 1997 with the Pinnacles National Park also being used as a release site from 2003 onwards. A release site was also established in Baja California in Mexico in 2002. Each release site is managed by a different partner who’s responsible for monitoring their flock’s movements, nesting attempts and survival.

The recovery programme has had many landmark moments. In 2002, AC-9 – the last wild individual to be taken into captivity – was finally released back into the wild. He’d been in captivity for 15 years, and upon his release he got a new name too, rebranded as Condor 21 on his identification tags.

It took time for the birds to breed in the wild again. The first wild-hatched chick successfully fledged in Arizonia in 2003. This was followed in 2004 by California’s first wild-hatched chick. In 2008, however, the programme celebrated its greatest milestone yet! For the first time there were more California condors flying free than in captivity. 

The one thousandth chick since the breeding programme’s launch hatched in 2019. While the birds are now reproducing on their own in the wild, the captive breeding programme is still regularly releasing condors, helping to boost the population. 

As of September 2024, Ventana Wildlife Society – which co-manages the central California flock – reports that there are now 343 free-flying California condors, with an additional 217 individuals in captivity. Each bird, including wild-hatched individuals, is tagged with a unique number and colour combination and tracked with a radio transmitter.

Threats to California condors

It’s been almost 50 years since the California Condor Recovery Program began and while there have been many successes, the birds aren’t out of the woods yet.

Birds of prey are one of the most at-risk groups of birds. Of those, vultures are particularly vulnerable. Despite being a protected species, a number of California condors have died from gunshots. For example, AC-9’s daughter Condor 526 was illegally shot and killed in 2018.

Unpredictable wildfires can also be deadly. For example, the Dolan fire in 2020, which was caused by arson, killed 12 of these precious birds and destroyed the Big Sur Condor Sanctuary.  

However, to this day, their biggest threat is lead poisoning caused by eating food containing lead bullets or fragments. In fact, lead poisoning is responsible for more than half of the California condor deaths between 1992 and 2022.

As scavengers, condors benefit from peoples’ hunting activities by feeding on the parts of animals that get left behind. In the USA, many states restrict the type of ammunition hunters can use in certain areas, but unless there are widespread lead bullet bans in the California condors’ current and future ranges, the birds will be at risk.

Power lines also pose a problem. Small birds can land on these without issue, but for California condors, they’re a deadly place to perch. If both of their huge wings touch more than one live line at the same time, it can send a fatally massive electric current surging through their bodies.

To get ready for release, captive condors take part in aversion therapy. Keepers encourage them to avoid power lines by rigging up a pole that gives them a light, off-putting shock when they land on it. They then take this knowledge with them when they’re released into the wild. It’s a tough-love approach, but it’s greatly reduced the number of fatalities. 

Even unhatched chicks face problems. On the USA’s central Pacific coast, the insecticide DDT is causing the birds to lay eggs with much thinner, more fragile shells. DDT was banned a long time ago, but these chemicals break down really slowly and are highly concentrated in the ocean. Scientists think condors may be being contaminated by feeding on dead California sea lions.  

Conservationists have also been keeping an eye on the progress of Highly Pathogenic Avian Influenza, more commonly known as bird flu. Multiple California condors were killed by the disease in 2023. USFWS and their partners have been busy vaccinating the captive breeding populations and free-flying condors to help prevent the spread of the disease and further fatalities.

The future of California condors

Efforts to improve captive breeding techniques and to grow the wild California condor population are ongoing.

Oregon Zoo, for example, have been trialling placing electronic ‘smart eggs’ in condor nests. These gather data that help keepers understand the best conditions for rearing healthy chicks. The smart eggs can also record sounds, such as the heartbeat and breathing of nesting adult condors and these can be played back to real eggs being kept in incubators.

In 2022, the Northern California Condor Recovery Program (NCCRP) began releasing birds in the Redwood National and State Parks, expanding the condors’ range to its most northerly point since recovery efforts began. This programme is led by the Yurok Tribe, with help from USFWS and the National Park Service.

In the Yurok language, California condors are known as ‘prey-go-neesh’. These birds are sacred to the Yurok and many other Indigenous cultures in North America. The NCCRP aims to re-establish the condor in the Yurok Tribe’s Ancestral Territory and the Pacific Northwest.

Another sign of hope is found in the IUCN Green Status of Species, which measures the recovery of depleted species. A species is considered fully recovered once it’s found in all parts of its range, including places it may no longer occupy but did before being disrupted by people.

The data shows that the California condor was prevented from going extinct thanks to rigorous conservation work. It also projects that, from a baseline of being largely depleted – meaning around 25% of a fully recovered state – with continued help, the species could improve to moderately depleted – around 75% of their fully recovered state.

We came very close to losing the California condor for good. While we’ve sometimes acted too late to save species, these birds are one of those important reminders of what we can achieve, even when a species is teetering on the edge of extinction. 

Though California condors may still be Critically Endangered, as efforts to restore the species continue, perhaps one day we’ll once again see them soaring widely across North America.