The World’s Rarest Crow Will Soon Fly Free on Maui
Hoping to succeed where past attempts have failed, scientists will reintroduce the clever corvid to the wild on a new island—a high-stakes conservation effort that requires a careful balancing act.
Haleakalā volcano towers above the island of Maui, a slumbering threat and a stunning refuge for Hawai’i’s fragile wildlife. Its rough-hewn and moonlike crater is home to endemic silversword plants and endangered seabirds, while its lush flanks shelter some of the most imperiled songbirds on Earth. Later this year, Haleakalā’s leeward slopes will become home to yet another endangered species, when the world’s rarest crow, called the ʻAlalā, is slated for reintroduction into the wild.
The planned release of five ʻAlalā, or Hawaiian Crows, to this part of Maui comes at a critical moment: These birds are already extinct in the wild, and previous attempts in the 1990s and 2010s to reintroduce captive birds to their former home on the Big Island of Hawai’i failed. The roughly 120 crows remaining in captivity are now the last buffer from total extinction, but scientists say the species is showing signs of wear from being cooped up, including fewer young born each year and a documented loss of their extensive vocabulary of vocalizations, or crow language.
Now, in the latest attempt to establish a wild crow population, biologists will investigate if this species can thrive on Maui, an island where it may have never lived before. Translocations outside of a species’ known historical range are rare in conservation work, but for a bird on the brink of extinction, it’s a necessary experiment: Scientists believe the crows will be safer from predators in a new locale—a main reason that past reintroduction attempts failed.
“ʻAlalā have been in [captivity] for way too long,” says Hanna Mounce of Maui Forest Bird Recovery Project, who is managing on-the-ground operations of the upcoming release. “This is a real opportunity to show some hope with Hawaiian species.”
The reintroduction is a testament to how conservationists are innovating in Hawai’i, with a now-or-never approach increasingly in play to save endangered species there. On Kauaʻi, botanists pilot drones with pincers to pluck ultra-rare plants from cliffs and propagate them, while in the Northwestern Hawaiian Islands, Black-footed Albatross have been jetted to Mexico to form a new colony better protected from sea level rise. And on Maui, Mounce and partners are now also setting the stage for one of the most ambitious projects yet—using mosquito-birth control to fight avian malaria, a disease that has been likened a “kiss of death” for Hawaiian songbirds. This new attempt to save the ʻAlalā is another example of high-stakes conservation.
In Hawai’i, where forests have become increasingly quiet from waves of extinction, the birds’ absence marked the loss of an especially gregarious voice.
Jet-black and playful, ʻAlalā are one of only two crows known to make and use tools. After Europeans arrived in the late 18th century, these charismatic birds began a steep decline from habitat destruction, shooting, and invasive species that ramped up in 19th and 20th centuries. A vastly shrunken population of wild crows stopped making babies in the early 1990s before disappearing completely from the wild in 2002.
In Hawai’i, where forests have become increasingly quiet from wave after wave of extinction, the birds’ absence marked the loss of an especially loud and gregarious voice. During his historic research into Hawaiians’ relationship to these birds, Noah Gomes, a Hawaiian bird expert who is on the release project’s cultural advisory committee, spoke with older generations who had grown up with crows when they still roamed as robust, noisy flocks. For some Hawaiian families, the crows are an ‘aumakua, a type of ancestral guide and family deity, he says, and it’s important to save the crows for those families. More broadly, he sees the reintroduction as an act of cultural revitalization for Native Hawaiians. “I think culturally speaking we have a responsibility to help the ʻAlalā,” Gomes says.
Previous reintroduction attempts started out well. The crows overcame early challenges, but both times disaster struck when the ʻIo—an endangered hawk endemic to Hawai’i, or the Big Island—began hunting and killing the released birds. This time around, project managers decided to move the birds further afield. Crucially, they knew hawks don’t live on Maui, the next island over, so the crows might be safer there.
Maui has no corvids today either, but bones discovered there indicate it did in the distant past. Whether those bones were the ʻAlalā or another, similar species is unclear, but Mounce says that doesn’t matter: She expects the ʻAlalā to fit in on Maui like a missing puzzle piece. Still, the move is experimental, and the release site on Maui is a little steeper and wetter than the species’ former home. Mounce and others advocate moving endangered birds to habitat that’s left in order to save them—wherever that may be. “I think that we need to be more willing to take risks,” she says.
However, on islands where so many species hang in critical balance, other ecological considerations loom. The released ʻAlalā will become neighbors to dozens of other endangered species on Maui, and scientists worry the large-billed, clever crows could gobble Maui’s stunning endangered tree snails, known as kāhuli, or the young of its six endemic songbirds. To address that risk, the crows’ new home will avoid overlap with snail’s territory. If the crows push in or if they start taking out other endangered birds’ nests, they’ll be brought back into captivity, Mounce says.
On islands where so many species hang in critical balance, other ecological considerations loom.
As the release date approaches, the crows have already undergone extensive preparation for life in the wild. Caretakers exposed the birds to a live cat to rouse their fear of the non-native predators and honed their foraging behavior by feeding them many Hawaiian fruits. Alison Greggor, a researcher with the San Diego Zoo Wildlife Alliance, helped prep the birds for their big day: “We try to give them the respect that you would give if you were caring for someone’s elder,” she says.
The next step is to acAPP the crows to their new environment in an aviary built for the release. After they’re set free, they’ll be closely monitored and fed using automated feeding stations at the release site as they learn to fend for themselves. Mounce’s team is also trapping non-native predators around the release site, including cats, rats, and mongooses, to reduce risk to any potential future crow chicks and eggs.
If the crows thrive in their new home, scientists may release several more birds at a second site on Maui. In the long-term, Mounce hopes these birds will create a sustainable breeding population on the island. Someday, a successful wild-born crow population on Maui—one that is savvier to predator risk than birds raised in captivity—could even repopulate Hawai’i Island, she says.
Such success could supercharge an entire ecosystem. The Hawaiian archipelago has already lost dozens of birds, such as flightless geese and rails, that disperse seeds—a critical ecosystem function for keeping habitat healthy. Known to eat over 30 fruits, a robust ʻAlalā population may help imperiled plants reproduce. “Their absence in the forest is having a huge impact,” says Gomes. “Even if we can get one established population breeding, that would be incredible.
Gomes has an even longer-term vision of success: a future in which the ʻAlalā and other Hawaiian birds become so abundant that Hawaiians can once again harvest them for food and ceremonial uses—as is done elsewhere in Polynesia. “It’s important that we as humans are interacting with the ecosystem,” he says. “That we are going into the forest and working with the birds….using them, talking to them.” The crows on Maui could represent a start.