The Elusive ‘Ua‘u
On the trail of a bird that yips like a dog, burrows like a mole, and keeps scientists up past their bedtime.

Shannon Wianecki
Photography by
Jack Jeffrey
Jay Penniman
David Quisenberry
Kim and Forest Starr
Zooming through the darkness, the Hawaiian petrels return from sea. Their weird and wonderful music fills the night sky above Lana‘ihale, Lana‘i’s tallest peak. Yips and squeals erupt against the forest’s black outline as the sooty grey birds tunnel into thick stands of uluhe fern to find their underground nests. Inside each burrow, a hungry fluff ball of a chick waits to be fed.
Those acquainted with these strange and marvelous birds know them from the remote, frigid summits of Haleakala on Maui and Mauna Kea on the Island of Hawai‘i, where they use their claws and beaks to burrow into volcanic rock. But fossils show that the rare seabirds once covered the Hawaiian Islands, from summit to sea. Large flocks of acrobatic petrels likely assisted early voyagers in finding Hawai‘i. The Hawaiians named them ‘ua‘u, mimicking their puppy-like calls. ‘Ua‘u chicks, fattened with squid and fish, were a delicacy reserved for Hawaiian royals.
Unfortunately, ground-nesting birds don’t mix well with burgeoning human populations. While ‘ua‘u are whizzes at sea, swooping, arcing, and flying over forty miles per hour, they’re clumsy on land. During the spring breeding season, parents take turns incubating a single egg and then caring for their helpless chick hidden underground. Juvenile birds can take up to 120 days to fledge. The family’s primary defense is invisibility—a strategy that likely worked well before the introduction of four-legged predators. Dogs, cats, and mongooses can easily find and scoop birds from their burrows; a single cat can decimate a colony in a night.
Urban lighting poses additional hazards for the nocturnal birds. Disoriented by bright lights, petrels end up stranded, often injured, on hotel grounds and ship decks. By 1967, predation and habitat loss had earned the ‘ua‘u one of the first spots on the Endangered Species List.
Awaiting the return of its foraging parents, a chick hides among roots and soil, invisibility its only defense from predators.
Photo: Kim & Forest Starr
Just two exits lead from endangered status: extinction and recovery. Recovery begins with biologists’ solid understanding of the species’ habits and whereabouts. Thus far, ‘ua‘u have proven mysterious. The pelagic birds spend the majority of their lives at sea. While counts at sea estimate a total ‘ua‘u population of 19,000, only around 1,500 birds nest at the summit of Haleakala, the state’s largest known colony. Where do the others nest? What pressures might they be encountering? Without this information, helping the ‘ua‘u escape extinction—the fate of so many Hawaiian birds—would be a near impossible task.
Enter Dr. Fern Duvall, the wildlife biologist for the Department of Land and Natural Resources (DLNR), and Jay Penniman, a researcher with the University of Hawai‘i Pacific Cooperative Studies Unit. These friends and fellow ornithologists are bent on helping the ‘ua‘u through the door to long-term survival.
Dr. Fern Duvall holds an ua'a chick
Photo: Kim & Forest Starr
Duvall has rescued countless stranded seabirds and testified before committees to reduce unnecessary urban lighting. Each spring, he gives public talks on best practices for protecting nesting seabirds. When Duvall consults the state’s Comprehensive Wildlife Conservation Strategy—an encyclopedic tome of Hawaiian bird info, he’s reading entries he wrote. His cell phone is even programmed with birdsong recorded in the field. (When Penniman rings Duvall, a shearwater squawks to announce it.) The clever ring tones are apt—when Duvall’s phone rings, it’s likely an injured bird needs his attention.
Penniman has similar feathers in his cap. Before moving to Hawai‘i, he censused and monitored seabirds on the Farallon Islands, the largest seabird colony in the continental United States. Ornithological books and artwork decorate Penniman’s home on Maui—including a lovely rendering of an ‘ua‘u by Duvall. Recently Penniman adopted an injured ‘ua‘u chick, hand-feeding the feisty, feathered toddler until its successful fledging. (This was a substantial commitment, considering that not only do ‘ua‘u typically take four months to fledge, they also emit a strong, musky smell.)
Certainly, if anybody deserves to be associated with what Penniman called in The Maui News “one of the remarkable discoveries of the century,” it’s these two.
Dr. Jay Penniman with a feathered friend.
Photo: David Quisenberry
That discovery took shape in 2006, when Duvall and Penniman followed up on a hunch that ‘ua‘u might be nesting on Lana‘i. Years earlier, while surveying for rare plants in Lana‘i’s cloud forest, Duvall stumbled across an ‘ua‘u that had recently been killed by a cat. In addition, a longtime Lana‘i resident had mapped sites where he had seen and heard petrels. Based on this evidence, Duvall and Penniman assembled a survey team along the four-wheel-drive road leading up to Lana‘ihale.