These parrots came to Los Angeles as pets – then went wild. Now scientists are unlocking their mysteries

A morning mist hung over the palm trees as birds chattered and cars roared by on the streets of Pasadena. It was a scene that evoked a tropical island rather than a bustling city in north-east Los Angeles county. “It feels parrot-y,” says Diego Blanco, a research assistant at Occidental College’s Moore Laboratory of Zoology, nodding to the verdant flora that surrounds us: tall trees and ornamental bushes with berries. Blanco and John McCormack, who directs the lab, have taken me to a street corner to look for some of the loudest – yet sometimes evasive – residents of Los Angeles: free-flying parrots. Most are a vivid green species with a shock of red at their head known as red-crowned parrots, but the LA basin also hosts a number of other parrots species – including the lilac-crowned, yellow-crowned and the Nanday parakeet. “You’d be surprised sometimes,” McCormack says. “They can be right above you and you don’t even see them.” Instead, you often hear them first. The two researchers name the birds squawking in the vegetation above us. Scrub jay. Band-tailed pigeon. Then Diego gives a yelp. “Oh oh oh, those are parrots!” he shouts, pointing upward. Indeed, a group of six bright green parrots have just flown overhead. We take off on a parrot chase – a very lopsided parrot chase, since they are soaring above the city streets and we are walking. As we follow the chattering flyers tantalizingly out of reach across the urban wilds of Pasadena, it’s clear: the parrots have the upper hand in this city. Birds of a feather escape together Their feathers are bright, their voices are loud. Some might even call them the ultimate Angelenos. The parrots were originally imported from Mexico and South America during a pet trade that peaked in the 1970s, and were often sold to celebrities. One story tells of a fire at a pet store, during which firefighters opened cages to save birds from burning – and the rest is history. In the years that followed they escaped into the wilds of the city – adapting, transforming and making the urban environment their own. Adaptable, creative and intelligent, today the parrot population numbers in the thousands. They are a common sight in certain neighborhoods: you can find them on the palm trees in Pasadena or all the way across town on telephone poles in Malibu. They have almost no predators outside of a few hawks or other raptors, and don’t compete with local birds for food, since they eat a diet of almost entirely imported ornamental plants. That means that while they are non-native, they are not considered an invasive species because they don’t push other species out. It’s not just Los Angeles: a 2019 study showed that 25 species of parrots have formed self-sustaining populations in 23 states around the US, including places such as Illinois and Connecticut. A team of researchers are now trying to better understand how these successful newcomers have adapted to their environment, evolving and interbreeding in unexpected ways. It’s a project that could hold lessons not just for Los Angeles but for cities around the world. “You’re never going to get all the things back to where they’re originally supposed to be,” says Blanco of the parrots’ impact on the city. “So now it’s just kind of like: who knew that this piece from that ecosystem happens to fit in well here? And what kind of new freak-o-system do we get when it’s all combined?” McCormack didn’t set out to study parrots in LA. He was a serious scientist studying native species of birds. Vibrant green parrots, on the other hand, were an introduced species – even worse, escaped pets – and their raucous squawking could drown out the gentler sounds of native fauna. It wasn’t as if others hadn’t studied them in the past, but it certainly wasn’t an activity for a serious biologist. “We started out sort of making fun of them,” says McCormack. But, he admits, “that hid something underneath – a certain longing to study them”. And then one day, inspiration hit – in the form of a parrot that collided with a library window at Occidental College, and died on impact. McCormack and his lab – specialists in birds – were called in to check it out. When they started looking closely at the specimen, they noticed hints of a scientific mystery: the bird did not look like any of the species that had landed in LA decades before. Instead, it bore traits of two of the different species that would never have met in the wilds of Mexico: the red-crowned parrot and the lilac-crowned parrot. It helped that McCormack was the curator of a vast Mexican bird collection that dates back a hundred years. He went to the catalog and started to poke around. Sure enough, the collection included examples of the same species in their native range in Mexico from before the pet trade got going, he says, offering a method of comparison with the urban hybrids. “We had this baseline example of what the birds looked like, as well as their genomes, before they were ever brought to LA.” Now, genetic analyses between the birds in McCormack’s catalogue and the specimens his team have collected is revealing how the LA birds are mixing. And they may even prove to be a key future link back to their original home. Clues to a hybrid mystery At Occidental’s Moore laboratory, McCormack opens a drawer of specimens collected in the 1930s in central Mexico. After nearly 100 years, the birds have retained their brilliant color – a green that looks like a chameleon, combined with purple or red feathers on their heads. He holds up the parrots to compare with the modern species – the ones that volunteers have brought Flapp (the Free-Flying Los Angeles Parrot Project) to study. Any parrot, freshly dead, with fewer than 10 bugs is a welcome addition to the project. Red-crowned parrots are the most common, he explains – and then there’s the sister species, the lilac-crowned parrots. They share a recent evolutionary history. Both native to Mexico, the red-crowned parrots live on the eastern coastal foothills of Mexico, while the lilac-crowned parrots are on the western coastal foothills. “In nature, they never come into contact,” McCormack says. “It’s been like one or two million years, they’ve gone their separate ways. But now they’ve been brought to Los Angeles, and they’re living together.” He lifts up a bird with red feathers on its head but dark skin around its nostril, a feature of the lilac-crowned variety. It’s a clear example of a hybrid variety that has become part of the city’s melting pot. The hybrids aren’t overtaking other species just yet – but they are an interesting nod to the impacts of city living. Genetic analyses of 40 to 50 birds have shown the way the parrots’ biology has shifted as well. The lab’s research also shows how these birds have adapted to conditions far outside the parameters of their home range – different temperatures, different trees and different rainfall. “They have definitely figured out how to live and thrive,” says McCormack. “Part of that is probably their own natural ability to withstand different conditions, and part of that is that the city is a buffer against extremes.” And in a remarkable twist, these thriving populations could be a lifeline for their cousins back in Latin America. The birds are now endangered in Mexico, where habitat loss and illegal trapping are putting their existence in danger. While working to conserve that population where it lives is key, some scientists see the potential for repopulating parts of Mexico with LA birds. The population in Mexico is believed to be smaller than the one in Los Angeles. “There’s this fanciful idea that, should they ever go extinct in the wild, you might be able to repopulate them from the urban populations from these arcs of biodiversity that occur in cities,” says McCormack. McCormack’s research also shows that some of the parrot species could spread. A new study shows the Nanday parakeet, which lives in the Santa Monica mountains, has adapted to live and feed on sycamore trees, and seem to prefer south-facing coastal canyons. The sycamore balls in California are fairly similar in size to the nuts of the carnaúba palm from their native range in South America. The team analyzed suitable habitat and said the parakeets could move next in the Santa Ynez mountain range behind Santa Barbara. Transplants find their flock Whatever their future role in conservation, the vibrant parrots continue to inspire admiration, curiosity and even a little frustration from local residents. Angelenos have a love-hate relationship with the birds, says Denys Hemen, a facility and operations manager at the Audubon Center at Debs Park in Los Angeles. “Some people think they’re a little noisy,” he says, “During the day, you might hear one or two chattering somewhere in the tree. I personally love them.” Those noisy calls are adapted to the environment of their homeland – shouting over treetops in the jungle – but they also work in the city. That’s because they communicate over fairly long distances, McCormack says. “They do a lot of flying during the day – they move around from tree to tree, foraging here and there. And because they’re so social, and they hang out in flocks, they need to communicate with each other.” Janel Ortiz, a researcher at Cal Poly Pomona, is focused on studying how they roost. How do the birds choose where to spend the night? (She has a hunch they actually use busy roads as a protective mechanism against predators.) And what do they do during the day? She also wonders about their chosen nesting areas for raising the next crop of Angelenos: the birds use cavities inside palm trees, and LA’s palm trees – planted decades ago – are starting to die or be cut down. “Are they going to be able to shift to a different type of tree, to be able to raise their babies?” Despite the challenges, the parrots’ numbers are strong – one study points to more than 3,000 red-crowned parrots alone, and that number is probably conservative. But they still face threats. Since the parrots are non-native, they don’t have any protections under California laws outside of basic rules against animal cruelty. People have tried to capture them in the past, such as an incident in 2023 when a man netted and killed several birds. The birds were added to the California Bird Records Committee in 2021, where they joined species that are not native to the state, but have become integrated into California ecosystems over the last century. And some scientists have argued that parrots should be offered sanctuary as endangered species living among us. It’s a testament to how beloved they are by many Angelenos. As the parrots soar over the sidewalk of Pasadena, Blanco points out how cool it is to have birds from so far away thriving in the urban jungle. “It’s like a little piece of the tropics that’s being brought here,” he says, his eyes trained to the skies. “They bring with them the imagination of those ecosystems.”