From Feral Cats to Speeding Cars, Hawaiʻi’s Native Nēnē Face a New Era of Danger

In December 2023, at a luxury resort on the Island of Hawaiʻi, three nēnē goslings hatched on a manicured green lawn. Within 72 hours, two were dead. One was found lifeless in a pond, and the other had simply vanished—likely the victim of mongoose predation, I would soon learn. Invasive predators, mongooses have decimated native bird populations since being brought to the islands in the 19th century, and the scene that likely played out at the Mauna Lani resort, whose lush vegetation and fresh water draw the geese and mongooses, has become a familiar one for those working to protect the birds. 

It was the single remaining gosling that drew me into the nēnē’s most recent struggle to survive. While staying at the sprawling beachfront property on a family vacation, I couldn’t resist photographing the gray fuzzy gosling with his parents. I noticed mongoose traps on the grounds and soon learned the about the brood’s backstory and the challenges nēnē face—old and new. 

Despite being the world’s rarest goose, the birds have adapted to live in a wide range of human-altered habitats, and people frequently spot them grazing on golf courses, waddling through parking lots, and building their nests beside paths in local parks. But across these sites, nēnē are struggling with a range of new risks: Surging colonies of feral cats prey on them, speeding cars run them over, and flying golf balls can even break their bones. As I learned about how all of these challenges threaten to upend the species’ hard-won recovery, I began photographing them to bring attention to the nēnē and the people working to help them.

Also known as the Hawaiian Goose, the nēnē is unique to the island chain and was once widespread across the archipelago. But by 1949, only 30 remained in the wild after colonization brought increased hunting, habitat destruction, and new predators like the mongooses. Intensive rescue efforts, including a captive breeding program, kept the species from going extinct, and today the nēnē —Hawaiʻi’s state bird and last surviving endemic goose—is hailed as a conservation success. As of 2025, an estimated 4,323 birds lived across the islands of Hawai‘i, Maui, Moloka‘i, and especially on Kaua‘i, the only island without a meaningful mongoose population. Though still listed as endangered in the State of Hawaiʻi, nēnē were downlisted from federally endangered to threatened in 2019. 

Yet in the modern world, this ancient bird’s continued comeback isn’t guaranteed. Populations on several islands, including Hawaiʻi Island, have dropped again in the past decade. Many risks stem from the nēnē’s high visibility and frequent contact with people, says Hawaiʻi Department of Land and Natural Resources biologist Raymond McGuire. “Nēnē being in public areas and coming into contact with humans is the big issue I’m dealing with,” he says, since it encourages risky behavior from the birds and exposes them to new dangers. “That’s how the population is going to slip away from us again.”

New Tech for New Threats

Few have done more to help the nēnē through this pivotal moment than Jordan Lerma, who has become a leader in ensuring the birds’ survival by combining technology and the power of community. In his day job, the Native Hawaiian marine biologist works to protect obscure ocean animals like dwarf sperm whales. But since his daughter was born in 2021, he’s also become focused on nēnē, which offer a more accessible way to connect people with conservation. “It makes me and my family really happy to see nēnē at the parks,” he says. “It is one of the few native species you can see at lower elevations.”

In 2022, Lerma founded the nonprofit nene.org to help save the birds while supporting the work of state and federal agencies. Biologists have banded 70 percent of the nēnē population and closely track their whereabouts through surveys and sightings reported by the public. To aid in monitoring, Lerma created an app that uses AI to identify a bird from a photo of its band, so biologists can snap a picture during a survey and instantly pull up the nēnē’s life history—detailing information such as the original banding location, most recent sighting, and any past injuries. 

On the Island of Hawaiʻi, Lerma has also deployed remote cameras to track the birds.  The cameras send images in real time to nene.org’s server, which logs the band number and updates the bird’s profile with the location. The combination of the app and the cameras provide immediate, extensive data about population size and health, informing conservation decisions. “When biologists are looking for a bird in particular, they can just look at the app and [say] ‘OK, it’s been out on this golf course for the past week,’” Lerma says. “That’s drawing on our cameras, that’s drawing on community, and I think it’s a win-win.”

One of Lerma’s first big successes came in 2023 when he harnessed data to protect nēnē from road strikes, which pose a major risk during the breeding season as birds move between nest sites and food sources.  At one restoration area, located near the city of Hilo and bordered by a busy road, nēnē were repeatedly killed by cars, and local advocates tried for years to get the speed limit reduced. To support their case, Lerma set up 6 custom speed monitors on the road for 10 days; he found that out of 5,000 cars recorded, 81 percent exceeded the speed limit. After he shared the data with the county, they reduced the speed limit from 35 mph to 25 mph within two months and shortly thereafter installed raised crosswalks and traffic-calming speed tables. No nēnē have been killed at the location since the changes were made.

Another recent and politically charged problem for nēnē are the feral cat colonies that have boomed across the Hawaiian islands as people abandon pet cats and others care for them. On the Island of Hawaiʻi, cats gather in areas where colony “managers”—often non-native Hawaiian residents, which adds to the controversy—stop by daily to fill water bowls and dump large quantities of dried cat food in aluminum pans and takeout containers. Though nēnē typically eat grass and plants, they unexpectedly developed a taste for the cat food, luring them toward these colonies and into danger.

Just a few miles from the Mauna Lani, feeding stations at a shopping mall draw dozens of cats. Nēnē have started nesting in the rocky areas next to the colony—an inhospitable area filled with flies, dried cat feces, mongooses, and even cat remains—risking predation of both adults and goslings. Walking through the adjacent parking lot, the geese also risk getting hit by cars.  Plus, nēnē can contract toxoplasmosis, a parasitic disease, from the cats, which can be fatal and is also correlated with increased risk-taking behavior such as crossing roads.  

Despite these threats, no one was officially tracking the cat colonies, so Lerma created a community science platform where anyone could submit their cat observations.  Building on that concept, he created FeralMap, which allows people to report additional introduced species like pigs and mongooses and publishes the sightings in a publicly accessible database. “People see nēnē every day. People see mongoose and cats and pigs every day,” Lerma says. “What we wanted to do was to create a way for folks to easily be able to share what they’re seeing.”  Additionally, he is working on regulations that would eliminate cat colonies and make cat abandonment more difficult. In late 2025, the County of Hawaiʻi passed a new law banning feeding feral cats on county property. 

Lerma is also trying to address the longstanding problem of mongooses through a trapping project. Plantation owners brought the small carnivores to Hawaiʻi to kill rats in sugarcane fields, but their plan faced a problem: Rats are nocturnal and mongooses are diurnal. The mongooses did not make a dent in the rat population, instead becoming a devastating predator for Hawaiʻi’s many ground-nesting birds. After gosling deaths at the Mauna Lani in 2022 and the one I learned about in 2023, Lerma and a team of volunteers began year-round mongoose trapping at the resort and nearby golf course nesting sites. In addition to traditional box traps, they imported modern traps from New Zealand, which are elevated off the ground and rely on liquid scent attractant. The efforts led to successful nesting seasons at the resort in 2024 and 2025—and when I returned to the Mauna Lani last year, I was happy to see the gosling I originally fell in love with all grown up and still living in the area.

Such success is promising, but the nēnē’s survival still hangs in the balance. While the population has increased overall since the 1950s, progress is uneven: 61 percent of the total population is on Kauaʻi, while nēnē on Maui and Molokaʻi have generally declined since 2019 and Oahu’s population disappeared entirely. After a period of decline, the population on the Island of Hawaiʻi appears to be increasing, thanks, in part, to Lerma’s efforts. As new threats emerge, biologists must invoke new strategies, because the work, as Lerma notes, “never ends.” He is banking on innovation, community science, and cultural stewardship to keep Hawaiʻi’s state bird from quietly slipping backward. “To me, it’s a species that shows that humans are a source of extinction but also there’s this underlying power that can reverse these actions,” Lerma says. “It makes me happy to see that we’ve been able to effect some good in a short amount of time on Hawaiʻi Island.”