Coming out of the dark about the Whiskered Screech-Owl

Let’s start with her astonishing eyes. They were huge. If human eyes were as large in our faces, relatively, we’d have eyes the size of large lemons. The yellow of her eyes was so intense, they seemed to glow, electric and incandescent. They were the only splash of color on her gray, well-camouflaged body.

I held her legs between my fingers and lifted her to my face, eye-to-eye with a Whiskered Screech-Owl, one of the least-studied and most mysterious of all 19 owl species in the United States.

I had joined David Oleyar, a raptor biologist with HawkWatch International, and his research team in the Chiricahua Mountains in southeastern Arizona, where he conducts what may be the only systematic study that includes the species. “It’s one of the groups of birds we refer to as ‘knowledge gap species,’” he says. “The combination of their small size, secretive nature, and nocturnal habits make them a challenge to work with.”

Plus, Whiskered has a more restricted range than its cousins, the widespread Eastern and Western Screech-Owls. In the United States, Whiskered is found in the mountains of southeastern Arizona and southwestern New Mexico — the region’s famed Sky Islands that are biodiversity hotspots and magnets for rare species. The bird’s range continues south throughout the mountainous forests of Mexico, Guatemala, El Salvador, Honduras, and to northern Nicaragua.

Oleyar had captured the female in a mist net as part of his study. She was so small: about 6 inches long and weighing 86 grams (3 ounces). I was about 1,000 times her size. Her eyes were framed by white eyebrows that swept into cute little ear tufts. She looked at me with only a casual, almost dismissive regard. I would love to know what she saw, looking at me. But her wall-eyed stare was wild and impenetrable. This experience was not about connecting with an owl. It was all about her intense animal presence.

Whiskered Screech-Owl
A Whiskered Screech-Owl clamps down on a branch before flying into the woods. Photo by Charles Bergman

‘A ver owl-ly place’

Oleyar has kindly blue eyes, a white beard, a ready laugh, and an affable, easy manner. He’s HawkWatch’s director of long-term monitoring and community science and is based in Utah. Last year, I spent a week in mid-July with him at the Southwestern Research Station, near Portal, Arizona. The Chiricahuas, Oleyar says, are an owl hotspot. “It’s the most species-rich location for owls in North America,” he said. “It’s unique on the planet. It’s a very owl-ly place.”

The station sits among spectacular red-rock cliff faces and sprawling pine-oak forests. Three times a day, the clanging of a triangle dinner bell called us to meals, like something out of the old west. We ate at picnic tables with a good view of a hardworking Acorn Woodpecker feeding a large and demanding chick in its nest hole in an Arizona sycamore. An Elf Owl had nested in the cavity a few years earlier, Oleyar said.

David Oleyar, a raptor biologist with HawkWatch International, collects data about screech-owls and other species of the Chiricahua range. He leads monitoring studies from the Southwestern Research Station, near Portal, Arizona. Photo by Charles Bergman

He studies six owl species at the station: Elf, Flammulated, Northern Pygmy, Northern Saw-whet, Whiskered Screech, and Western Screech. Chatting after lunch, I asked him why he had chosen to study small owls and not just owls in general.

“Apart from the general charm of these little owls, they are mostly unstudied,” he explained. “Especially compared to the big owls.”

The Whiskered Screech-Owl is a good example. “There are few, if any, other long-term studies of the Whiskered,” he said. His mentor, Fred Gehlbach at Baylor University, did some work on the species, but his main interest was the Eastern Screech. “That’s it, for the most part,” Oleyar said.

The Whiskered’s restriction to such a small area in the United States makes it highly sought by birders. Partners in Flight estimates the global population is 200,000 birds, about 500 of which live in the United States. Arizona is home to the bulk of the U.S. population; only 20-25 pairs are known to occur in New Mexico (in the Peloncillo Mountains), according to New Mexico Avian Conservation Partners.

BirdLife International does not provide a population estimate, and it describes the species as “increasing.” By contrast, American Bird Conservancy says the owl is “decreasing,” and the 2016 edition of the State of North America’s Birds report included the owl on its Watch List.

“These are the best estimates these groups have,” Oleyar said. “They are coarse at best and highlight the need for more efforts to survey this species and the other small owl species.” That’s one of the reasons his project is working on population numbers, ranges, and changes over time among small owls.

Educators Kathleen Morrow, a participant in EarthWatch’s Teach Earth program, admires a newly banded owl before letting it go. Photo by Charles Bergman

Working with teachers

During my week at the station, we were joined by a group of 10 elementary and high school teachers who were there to volunteer and learn about small owls. The teachers were studying with Oleyar as fellows in EarthWatch’s Teach Earth program. It embeds teachers with world-class scientists on research expeditions. They work as community scientists, learning research protocols, gathering data, and gaining an appreciation of how knowledge is gleaned. Through the inspiration they gain with the owls, they work on lesson plans that can bring science to life for their students.

“Any program that brings teachers to the field to experience conservation while working on plans for engaging their students in the same has immense value,” Oleyar said.

The teachers came from all over the country, largely working in urban school districts with diverse student populations. Several taught biology or chemistry, while others taught art and English Language Arts, and one was a grade school librarian.

Kathleen Morrow, a biology teacher at Thomas Jefferson High School for Science and Technology in Alexandria, Virginia, spoke of the importance of science education, particularly in the current political climate. “This is a rare opportunity to demystify science and what scientists do on a daily basis,” she said. “And it gives a chance to connect with nature in a deeper and more meaningful way. We need more of these experiences, especially for young people.”

It’s hard to imagine a time in our history when an emphasis on science literacy in schools could be more important or relevant.

During our week studying owls, the signs of the climate crisis were inescapable. Europe was suffering through a “heat apocalypse,” and rivers like the Loire in France were drying up. And closer to home, a 22-year megadrought has the reservoir at Lake Mead on the Colorado River at 30 percent capacity. Water levels are approaching “dead pool,” meaning the water may be too low to flow through Hoover Dam.

Of course, in the wider cultural climate, hostility to science is growing. The pandemic laid bare a virulent anti-science sentiment in our country.

It would be easy to feel cynical. Yet these teachers gave me a measure of hope. They sought deeper and more meaningful experiences in nature and wanted to make a difference on behalf of our fragile planet. That’s heroic in my view.

Whiskered Screech-Owl
A Whiskered Screech-Owl receives a leg band as part of the HawkWatch study. After being caught in a mist net, owls are quickly weighed, measured, banded, and released. Photo by Charles Bergman

Doing owl science

We learned science by doing science, proceeding on two tracks: owl surveys at night and the search for tree cavities by day.

For both activities, Oleyar taught us what we needed to know in class sessions, and we put it in practice in the field. For the nightly owl surveys, we learned how to identify owls by their calls, how to play back calls, how to enter data, and how to use a mist net to capture owls.

Each night after dinner, we headed into the mountains. Usually, we divided into two teams. One team went with Oleyar, another with his colleague, Jesse Watson, who manages HawkWatch’s banding programs. Watson’s team also included Kassandra Townsend, a Ph.D. candidate working with Oleyar.

To say we looked for owls at night is misleading. You don’t really “look” for owls in the dark. You listen for them. We followed a carefully orchestrated protocol for using recorded playbacks, involving several minutes of silent listening in the dark, punctuated by playback of the calls of the owls. We played the calls of each of five species. (The Northern Pygmy-Owl is not included because it is largely diurnal.)

Whiskered Screech-Owl makes a steady cadence of five to eight hoots, like Morse code, changing pitch at the end. The call is the only reliable way to distinguish the Whiskered from the closely related Western Screech-Owl, which gives a bouncy call.

When an owl responded, we broke out the mist net and waited for the silent thud of an owl crashing into the net, as unmistakable as the tug on a fishing pole when you’ve got a hard strike. And every bit as exciting. There followed a flurry of bouncing headlamps and science in action. The owl was disentangled from the net, weighed, measured, banded, and released. All with remarkable efficiency.

The highlight of the week for everyone, unquestionably, was the opportunity to hold the adorable little owls and let them go.

Going into the final night of our surveys, we had caught nine owls. Every one was a Whiskered Screech-Owl. I was surprised. I’d thought we would capture more species, which led to the inevitable question: Why only Whiskered?

Oleyar was not entirely sure. “It’s the first time we’ve had a group here this late in July. It might be because it’s one of the most abundant species of owls in the area.”

We were all eager to see other owls. An Elf Owl? A Flammulated Owl?

But no regrets at all. I came to love the plucky little Whiskered Screech-Owls. And we were all happy to help Oleyar gather lots of data on the enigmatic little birds.

Still, every night we went out wondering what other species the darkness might cough up.

The forests of Arizona’s Chiricahua Mountains are home to screech-owls and many other bird species, attracting birders year-round. Photo by Charles Bergman

Depending on tree cavities

All six of the small owls share one behavior in common. They all nest in tree cavities. They don’t make them. They don’t even alter them. They rely on woodpeckers and other creatures to make cavities, or they find a hole in a broken branch.

They take the cavity as they find it.

That means cavities are the ecological center of the little owls’ world. They are the key to understanding the owls’ habitat and conservation. And perhaps they’ll tell us about the varying assemblages of the owls over time as they respond to climate change.

What makes a good cavity for owls? Do they compete for them? Are cavities a limiting factor for small owls?

The cavities took us to the nitty gritty of the research project. In several workshops, we learned the skills required to map cavities and gather data on them. Oleyar taught this material like a master class in wildlife conservation methods and data collection.

We learned to identify the many species of oaks, pines, and junipers, as well as the Arizona sycamore and Fremont cottonwood. We learned to measure their girth or dbh (diameter at breast height). We learned to lay out study plots and characterize the plots by tree species, tree sizes, and numbers of trees, as well as canopy cover.

We practiced looking for cavities and entering data such as GPS coordinates, height of the cavity, species of the tree, and bearing.

A camera attached to a long pole peeks into a potential nest cavity for owls. The camera allows biologists to inspect cavities without needing to climb trees to check nests. Photo by Charles Bergman

We learned to use an innovative camera attached to the end of a long pole. Inserted into the cavity, it sent a video to a small screen that we held in our hands. It enabled us to see inside cavities to determine their contents (which we hoped might be a roosting owl or chicks). Oleyar called the camera a “game changer” in owl studies: It eliminated the need to make dangerous climbs up trees to check nests.

Then we rated each cavity on a scale of 1 to 5 (5 being the highest). If the cavity looked promising, we gathered yet more data on microhabitat — including nearby tree species and temperature inside the cavity — as part of Townsend’s Ph.D. research on cavities.

On the last full day, we went into the field and put the whole process together: from laying out plots to entering data on trees to mapping cavities. So far, Oleyar has mapped 2,150 cavities in trees. He has found that in the Chiricahuas, 30 percent of the nests are in Arizona sycamores.

As he explained, the cavity study will enable “a sharper focus on conservation issues.” Save the cavities, save the owls.

The impact of learning science from the inside was powerful. Brianne Loya, a 10th grade biology and chemistry teacher at Phoenix Union Bioscience High School, described the last day in the field as “putting it all together.” This was not just about learning new ideas or information, she said, “but about how science ‘knows.’ This was very meaningful to me.”

Oriana Nir, a ninth grade English Language Arts teacher in Boston Public Schools, found the experience of the week transformative. She felt great “contributing to knowledge through citizen science.” But the experiences went deeper. “I have reimagined who I am in relation to the natural world,” she said, “and what I can offer others in discovering and preserving the wonders of this world.”

Through a rigorous application of scientific method, we were learning to see a tree the way an owl might see it. We found lots of cavities. Only one looked really promising. I hoped an owl would nest in it the following breeding season.

Educator Oktay Ince, a participant in EarthWatch’s Teach Earth program, holds a newly banded owl before releasing it. Photo by Charles Bergman

Team Owlsome

“Jackpot!” Lauren Hubert exclaimed. She is a science teacher in Phoenix. It was about 1:30 a.m. on what proved to be our fifth and final owl survey. Our two teams had just reunited after our surveys. That night, I was on Oleyar’s team, which the teachers called “Team Owlsome.”

Hubert, who was with the other squad (dubbed “Jesse and the Owls”), was ebullient. In addition to hearing all five species in the protocol, her team caught a Western Screech-Owl, the only owl captured that was not a Whiskered.

Our team heard four species and had three captures, but only two were new owls. One was a recapture. After being netted once, it followed us as we worked our way down the mountain and was netted a second time.

We captured 12 Whiskered Screech-Owls for the week. Three were recaptures. Throughout the summer, Oleyar caught 22 Whiskered Screech-Owls, six of which were already banded.

As we walked through the night from one playback location to another, Oleyar told me that they’re not ready yet to draw conclusions about owl conservation and forest management. The 2022 season was the fifth year of the project in Arizona out of a hoped-for 15 years. He expects to publish numerous studies from the research and says it won’t be too long before the first works are submitted to academic journals.

None of the small owls is federally listed. Several do have protection at the state and local levels.

It may be that climate change is already affecting population numbers and relations among the species. The large number of Whiskered Screech-Owls suggests they “are becoming more abundant.” This is pure speculation, Oleyar emphasized, but it may be “winning the competition with the smaller Flammulated Owls for nest cavities.”

As for me, I decided to return early in the next breeding season, when the owls of other species are more active. I want to see if the good cavity we found gets used as a nest. Maybe, too, I’m taken by these owls. Sometimes, once is not enough.

Whiskered Screech-Owl at a glance

As a group, screech-owls do make screeching sounds that they are named for, but they’re not as common as their other vocalizations. Whiskered Screech-Owls give a variety of trills and whistles that are used in pair bonding, to declare territories, and to advertise nest cavities. When predators or intruders are nearby, the owls produce a series of calls that increase in intensity depending on the circumstances: from a hoot to a bark to a screech.

The name “Whiskered” comes from the bristles on the ends of the bird’s facial feathers, which are difficult to see unless you’re holding a bird in the hand.

The screech-owl prefers montane pine-oak and oak forests and canyons with oak and sycamore trees. The species is found at elevations from 1,000-2,900 meters (3,280-9,514 feet) from southeastern Arizona and southwestern New Mexico to northern Nicaragua.

Since 2018, eBird users have reported the bird at several canyons in Arizona, including Cave Creek, Madera, Huachuca, Ramsey, and Miller and on Mt. Lemmon. In New Mexico, most reports have come from Clanton Canyon.

This article appears in the May/June 2023 issue of BirdWatching magazine.

Birders guide to southeast Arizona

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