Issue 18.1: February/March 2015
Department

Pueo of the Sun

Mystery surrounds Hawai`i's only native owl
Story by Sheila Sarhangi. Photos by Jack Wolford.

On a chilly November afternoon along Hawai‘i Island’s old Saddle Road, I’m about thirty seconds into a staring contest with a pueo. When I open the door of my car on the grass shoulder of the highway, it leaps from the fence post, pulses its wings and disappears behind a hill.

Five minutes later it’s back, this time about thirty feet overhead, peering down at me. It glides, claps (yes, claps) its wings under its body and gives a low hoot. “Is all this for me?” I wonder, until I hear another clap in the distance and a second pueo appears. The hoots and claps continue for another minute until I lose them in the late after-noon fog. Later, I learn this is typical courting behavior—definitely not for me.

Pueo, or Hawaiian short-eared owls, are found on all of the main Hawaiian Islands, from sea level to eight thousand feet. They’re stunning, with piercing yellow eyes, brown- and gold-streaked feathers, a beige breast and a circular face trimmed with a white, masklike ring. They’re medium size as owls go, and unlike most of their counterparts they’re diurnal, or active during the day, when they hunt for rodents, lizards, insects and other birds in open areas: grasslands, shrublands, parklands and near roadsides. People often mistake pueo for the only other owl found in the Islands, the barn owl—introduced in the late 1950s to control rodents in cane fields. But barn owls are larger, with a white, heart-shaped face and black eyes, and they’re mostly nocturnal.

Despite the fact that they’re frequently seen and well loved in the Islands, not much is known about pueo. Research is thin. Their numbers haven’t been determined. No distribution map exists. Some scientists even call them “the mystery bird,” which seems ironic because they’re highly visible, they hold a significant place in Hawaiian culture and they are Hawai‘i’s only extant native owl.

Why is this the case? For one, the pueo’s commonness works against it, at least in terms of scientific study. “Though we know pueo are declining, they are still more numerous than many of Hawai‘i’s single-island, single-mountain or even statewide birds,” says Fern Duvall, wildlife biologist for the state’s Department of Land and Natural Resources. “So they fall short of being able to easily get research dollars, as charismatic as they are.” Sheila Conant, former chair of the University of Hawai‘i at Mānoa Zoology Department, who has studied Hawai‘i’s native and endangered species for nearly fifty years, agrees with Duvall and adds another reason for the lack of attention: “To really learn about an animal or why it’s declining, it’s ideal to use technology to track individuals”—devices such as satellite tags and radio collars. The challenge there, she says, is catching them. Pueo nest on the ground, not in holes or in structures, which makes it tough to find their nests. And if someone does find a nest, Conant says, it’s difficult to capture pueo without scaring them away. “Sure, you can drive the Saddle Road and see them flying around, perched on fence posts and hunting. But that’s a long ways away from catching a bird and putting a device on it,” she says.

The known threats to pueo are similar to those facing Hawai‘i’s other native birds: loss of habitat, disease and introduced predators. Pueo eggs and chicks are vulnerable to cats, mongooses, rats, dogs and ungulates, like pigs. In the 1960s many dead or moribund pueo and barn owls were mysteriously turning up, mostly along Hawai‘i roadsides. The malady was coined “sick owl syndrome” for lack of a better term, and it’s still occurring. Some say
trauma from car collisions is the cause, because pueo hunt mice scurrying across roads. Others posit that natural fluctuations in mice and rat populations could be leading to stress and starvation. Another possible culprit is secondary poisoning from rodenticides applied by farmers, hotels and homeowners. No one knows for sure, and no one’s currently studying it—one more mystery around Hawai‘i’s mystery bird.

Pueo (Asio flammeus sandwichensis) are an endemic subspecies of the short-eared owl (Asio flammeus), which is widespread across North America, South America and Eurasia. They’re great colonizers, with ten subspecies in all, including endemic short-eared owls in Puerto Rico, on the Galápagos Islands and on Pohnpei. Re-searchers aren’t sure how long they’ve been in Hawai‘i, but Helen James hopes to find out. Since 1977 James, paleo-ornithologist and curator of birds at the Smithsonian Institution, has been on a quest to document the fossils of every bird species that lived in Hawai‘i, including owls. James notes that a long-legged owl lived in Hawai‘i from at least 250,000 years ago to as recently as only a couple thousand years ago. The question of when pueo arrived in the Islands has been on her mind “for a very long time,” she says.

In 1982 James and her research partner Storrs Olson published a study that suggested pueo colonized the Hawaiian Islands only after the first Polynesian voyagers introduced the Pacific rat—a nice food source for the birds. To reach this hypothesis, they compared pueo morphology with that of their continental counterparts. They looked for differences in size, plumage or beak shapes, and they did a visual comparison of their bones. The conclusion: “We didn’t see any significant differences,” she says, at least not the kind of differences one would expect to see if pueo evolved independently from other short-eared owls over a very long time. “The fact that pueo and the short-eared owl were similar is consistent with the idea that pueo haven’t been in the Islands that long,” she says.

But that study hasn’t put the question entirely to rest. James is now radiocarbon-dating the bones of pueo found across Hawai‘i—in lava caves on Maui and Hawai‘i Island, in karstic sinkholes on O‘ahu and in a limestone cave on Kaua‘i—to better determine when they arrived in the Islands. “Once I’ve accumulated all of the dates,” she says, “I think we will finally know when pueo got here.”

Another question surrounding pueo—whether or not they are a distinct subspecies
of short-eared owls—is closer to settled. This might seem like an academic point, but it has real-world implications: If pueo aren’t much different from the world’s millions of other short-eared owls, then it’s harder to get funding to study them. In a recent study Peter Pyle, a biologist at the Institute for Bird Populations and a research associate at Bishop Museum in Honolulu, separated male and female pueo and then compared their plumage with that of Mainland owls. “Once sex is factored in, I’ve found pueo to be nearly 100 percent separable,” says Pyle, pointing out that pueo are smaller and darker than their Mainland cousins—enough to consider them a separate subspecies. To confirm this, Pyle and his colleagues at the Smithsonian intend to perform a genetic analysis. But even if pueo are a distinct subspecies, Pyle suspects that James’ and Olson’s 1982 hypothesis that pueo colonized the Islands only after the rats could still be right. “That would then be a good example of how rapidly plumage and size can change to form a subspecies, despite fairly recent isolation,” he says.

An interesting side-note to all of this, says Pyle, is that short-eared owls have recently colonized Johnston Atoll, about one thousand miles southwest of the main Hawaiian Islands. Whether they are pueo or continental birds isn’t known, but Pyle and his colleagues hope to find out. As part of his study, Pyle examined owls in the Northwestern Hawaiian Islands, which arrive during winter and appear to leave in spring. He found that most of them—not all have been identified—are continental short-eared owls and not pueo, as some had thought.

Regardless of how long pueo have been in the Islands, they have become an important figure in Native Hawaiian culture. Many Hawaiian families consider pueo an ‘aumakua (ancestral guardian) who protects, aids or guides them. “Pueo ‘aumakua were known to signal warnings of imminent misfortune (e.g., a house was near collapse), danger (e.g., a person was about to be in an accident) and death (e.g., a person was near death or had died),” write Verna L.U. Amante-Helweg and the aforementioned Sheila Conant in Conservation Biology of Hawaiian Forest Birds. “These messages were given in the form of a cry or hovering behavior.”

An ‘aumakua, however, is much more than just an animal. “The owl is not the ‘aumakua; it is the physical manifestation of a kupuna [ancestor] who has passed on,” says Sam ‘Ohu Gon III, senior scientist and cultural adviser for The Nature Conservancy of Hawai‘i. “The ‘aumakua are essentially elders who are no longer with you in this physical plane, but you still have a relationship with them.” Think of them as a channel of communication—a connector of sorts—to ancient relatives. An animal can also be a kinolau (physical manifestation) of an akua, or god, such as Kū, Kāne, Lono or Kanaloa, explains Gon. In that case the animal would have great power.

Many Hawaiian mo‘olelo (stories) feature pueo ‘aumakua. Perhaps the most famous is the story of Kapo‘i, also known as the battle of the owls. Kapo‘i, who lived in Honolulu, found seven pueo eggs and took them for dinner. That night an owl alit on his fence post and asked to have her eggs back. Though he was hungry and poor, Kapo‘i returned them. Thus the owl became his ‘aumakua and asked Kapo‘i to build a heiau, or temple. This he did, as a human must obey his or her ‘aumakua’s requests. But Kakuhihewa, the king of O‘ahu, hadn’t yet consecrated his own heiau, and interpreted Kapo‘i’s construction as an act of rebellion. He ordered Kapo‘i to be killed. Kapo‘i’s pueo called on owls from all of the islands to help, and they defeated Kakuhihewa and his army. The king recognized Kapo‘i’s owl as a most powerful ‘aumakua, known as Kūkauakahi. The takeaway: Those who are unselfish will
be rewarded.

Gon says more modern stories of pueo are of “someone falling asleep at the wheel and a pueo wakes them, saving their life,” or “a pueo startling a hiker on a dangerous trail, right before they were about to fall off a cliff.” You can rationalize your way out of believing what happened, he says, or you can go with the flow of the experience. “The fact that people maintain their strong relationships with pueo today, even though so much of the native landscape has been lost, is a testament to their persistence within our human realm.”

Every winter at Maui’s Kanahā Pond —a wildlife sanctuary with 245 acres of coastal wetlands—Fern Duvall gets a front-row seat to a spectacular aerial show put on by a pair of resident pueo. “The pueo fly way up in the air, about a thousand feet above ground, and make huge circles around each other, with these slow, moth-like wing beats,” he says. “This goes on for several rotations, and you can even see them flying backwards at some points. It’s a pretty remarkable sight.” Because pueo typically nest in flat, treeless areas, says Duvall, there’s nothing for them to perch on to make their territory known. “So they have these aerial displays that show all of their competitors, ‘This is my female, and I’m flying in a big circle and this is where I’m going to be nesting,’” he says. Duvall says three resident pueo pairs have been producing chicks in the sanctuary since he started managing the pond in 1996. It’s a much-needed haven from cats, rodents and mongooses, which are trapped to preserve the sanctuary’s inhabitants.

As for the future of pueo, Conant says the number one thing that would produce more information about pueo and potentially lead to their recovery is a biologist who was determined to study them. “In conservation, sometimes we get closer to solving problems if there is a champion of the species,” she says. “As far as I know, there isn’t anyone out there finding out everything there is to know about the pueo.” Any takers? HH

Story by Sheila Sarhangi. Photos by Jack Wolford