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November 5 - November 28, 2023
When cornered in their burrow by an intruder, the chicks will buzz exactly like the rattle of a rattlesnake. “Batesian acoustic mimicry,” as it’s called—when a harmless species imitates the sound of a dangerous one—is not unique in the animal world. It’s a kind of evolutionary “ruse” that protects the mimic from would-be predators.
In his video Wings of Silence, a visual exploration of nine species of owls in Australia, filmmaker John Young shows a chilling scene in a hollow containing a barn owl nest: one owlet killing and eating its smaller and weaker sibling.
Scientists have also seen instances of cannibalism among other owl species. During times of food scarcity, older and stronger siblings will kill and eat the younger and weaker ones. Nestling screech owls have been known to fight fiercely among themselves for food and to kill their smallest sibling. Australian researcher Raylene Cooke found juvenile Powerful Owl remains in eight out of nine pellets she dissected from one Powerful Owl nest.
Not long ago, Pauline Ducouret and her colleagues at the University of Lausanne found that older nestling barn owls can be impressively generous toward their smaller, younger siblings, donating portions of their food to them on average twice per night—a display of altruism thought to be rare among nonhuman animals.
are ready to leave the nest: branching. Once nestlings can regulate their own temperature, but before they can fly, they may branch, clambering out of the nest and wandering out onto a limb or even jumping to branches of neighboring trees.
To climb back into the tree, they’ll use a slanted “whip”—one of those downed trees leaning up again the nest tree—or go straight up a trunk if there are enough branches, crawling upward with their strong feet, hooking their bill like a parrot, biting into the bark for purchase, and flapping their wings hard. Some owls even have vestigial wing claws that may help with the climbing.
Soon after branching, owlets start taking short flights from one tree to the next. “It’s kind of comical, fun to watch,” says Mendelsohn, “like watching a toddler learning to walk. They get going and then they can’t stop and just crash into something or fall over or just completely miss their destination.”
It’s not clear whether owls sleeping with an eye open are experiencing sleep in only half the brain the way some birds do. During this so-called unihemispheric sleep, one cerebral hemisphere is awake while the other slumbers, and the eye connected with the awake hemisphere stays open to monitor the world, allowing a bird to stay alert to danger and adjust to changing environmental conditions.
In general, larger owls are more resilient to cold than smaller owls. Great Horned and Great Gray Owls are large and well insulated with downy feathers. Big-bodied Snowy Owls are especially well adapted to frosty temperatures, with feathered feet and a dense layer of insulating feathers so effective they’re second only to Adélie Penguins of Antarctica at retaining body heat, allowing the owls to endure temperatures down to −40 degrees Fahrenheit.
The winter roosts may be a spot for the birds to find mates and then stay to breed locally for the next breeding season.
Why the birds are here in Serbia in such great numbers has to do with agriculture, specifically with food supply for the owls and the agricultural methods that sustain it. The whole region of northern Serbia is agricultural, and farmers avoid rodenticides and use more old-fashioned methods of harvesting that leave plenty of grain on the ground.
Back in 2007, Ružić recalls, “a lot of Serbians believed superstitious things about the owls. ‘If there’s a Little Owl on the top of the house calling, somebody in the house will die,’ that sort of thing.”
In two or three years’ time, Ružić could see positive change in communities around the region. Today, if you try to walk in Kikinda, you’re stopped by dozens of people who want to show you the best tree in town with the biggest number of owls,” he says. “The local community has become really proud of what they have.”
“To see the attitude change like that over the past ten years—it’s one of the things I will take with me when I leave this planet,” says David Lindo.
Around 90 percent of the owls roost in birch trees, he says. But as fall progresses and the leaves drop, they slowly shift to conifers, and Ružić thinks it’s the most experienced ones that do this first and get the best spots.
Why are these owls coming to roost in such numbers in villages and towns? Why aren’t they roosting in natural areas? For one thing, like any good roosting site, villages offer shelter from weather and from predators. The winters are cold, and the winds are strong. The region is completely flat, and there are few trees, few forest roosts, especially after the broadleaf trees lose their leaves, so there aren’t many places for the owls to hide or find cover.
We had one owl that would roost on top of a mountain and fly three miles down into the valley to hunt along the edges of a dairy farm in this wooded stream valley, and then it would fly back up to the top of the mountain and roost at night. Until we started tracking, we had no idea these birds were doing that.”
Though many saw-whets are faithful to their routes, they don’t appear to be migratory in the conventional sense, moving between the same wintering and breeding grounds every year.
In Finland, owl researcher Erkki Korpimäki found that female Boreals (the bigger sex) migrate south from colder regions to areas with more plentiful food, and the adult males remain up north, closer to spring breeding territories.
Holt has analyzed 14,000 Snowy Owl pellets containing the remains of more than 43,000 items of prey and has found a diversity of animals represented there, 33 species of mammals and 20 species of birds. But in the breeding season, the Snowy’s diet is 99 percent lemmings.
Many of the birds will stay on their breeding grounds through the winter while others explore from winter to winter, traveling from Alaska to Russia and back. One radio-tagged Snowy traveled 600 miles in a single day.
Like most licensed care providers for owls, Laura Erickson will go on at length about the difficulties of keeping a real owl—and also the joys.
The family took him to a rehabilitation clinic, where he was nursed back to health. But because he ended up imprinting on humans, he couldn’t be released into the wild.
To exercise him, she ran him around the neighborhood at night. She would put little jesses or straps around his legs, attach them to a leash, and start running. He would take off and fly right above her head.
In most countries, keeping an owl without a special permit is illegal. The United States forbids people to have owls as pets. Only if you’re trained and licensed can you keep an owl for rehabilitation or for educational purposes, or, in some states, for falconry.
In the past, owls—known as Burung Hantu, “ghost birds”—were little in demand, but after the release of the Harry Potter books in Indonesia in the early 2000s, their popularity boomed.
Japan is the largest global importer of owls, accounting for more than 90 percent of the thousands of owl imports.
the loss of his alula, a small bone at the tip of the wing that’s critical for all kinds of flight maneuvers. The bone itself has feathers embedded in the soft tissue surrounding it, and when it moves, it elevates or depresses the feathers, changing the airflow over the wing to control different flight movements, such as deceleration and landing.
The vet team uses sophisticated diagnostic techniques, examining the owl’s body, doing blood work, and inspecting fecal samples. The stories that emerge from the vets’ careful sleuthing reveal the threats these owls face on a daily basis. They also become teaching tools.
Of the eighty or so owls admitted to the center each year, most have probably been hit by a car while searching the roadside for food.
They restore essential flight feathers on the wing and tail through “imping,” a remarkable technique in use since the thirteenth century in birds used for falconry. “We clip the damaged feather near the base, leaving a hollow keratin sheath,” explains Pierce. A matching feather molted from a donor bird is cut to length and inserted into the sheath with a tiny keratin dowel and then superglued to keep it in place. “If all goes according to plan,” she says, “the imped feather serves as a good replacement for the original feather until the bird molts it naturally, dropping the imped feather and
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The rodenticides people use to kill rats contain toxic compounds that inhibit blood clotting, which eventually leads to severe internal bleeding and death—not just for the rat itself but for the raptor that feeds on it.
One young Eastern Screech Owl found sitting quietly on the ground at a city park in Charlottesville had no apparent external injuries, but an X-ray revealed a skull fracture, and a blood test showed a significant amount of lead coursing through the owl’s veins.
Testing owls for lead poisoning is a relatively new thing. Lead analysis used to be routine only in eagles and vultures, scavengers that were likely to feed on the gut piles that hunters leave behind, laced with lead fragments from bullets. But there’s a growing concern that owls are also ingesting lead from spent ammunition, perhaps by eating a squirrel that was shot but not killed and still carries bullet fragments.
When an owl chick hatches, it doesn’t instinctively know what it is. Imprinting on a member of its own species helps a baby bird learn and interpret species-specific behaviors and vocalizations so it can choose appropriate mates later in life. If an owlet imprints on a human, the owl will never be owl enough to survive in the wild.
When we name the ambassador owls, we pick a name that has to do with the bird’s injury or its natural history or its scientific name so it becomes a touchstone for educational discussion.”
Those two small owls taught Buhl five big things. First, when you’re training an owl, you need to consider the natural history of that species, which shapes its response to human contact.
Second, owls are individuals. They have different personalities and respond to training in different ways.
Third, if there’s a choice between safety and food, owls will choose safety.
The fourth and biggest lesson was this: owls have emotions.
Finally, the saw-whets taught her what emotions look like in a small owl, how fear and distress show up, as well as feelings of comfort, relaxation, of “safety.” And, perhaps most important from the perspective of the bird, what triggers these feelings, how the presence of a human, especially a human trainer, affects an owl.
Humans never lived in the cave, says eminent French prehistorian Jean Clottes, the first specialist to investigate Chauvet after its discovery. It was used only for painting and maybe for ritual and worship. The owl, like the other animals, was drawn not out of casual interest or for aesthetic pleasure but to invoke spirits, he argues, to ask for their help.
At one site in France, Combe-Saunière, scientists found the bones of close to a hundred Snowy Owl wings—not the carcasses, just the wings. At another, Saint-Germain-la-Rivière in southwestern France, archaeologists discovered the remains of 22 male and female adult Snowies, some with decorative carvings on the bones. These finds suggest that 20,000 years ago, hunter-gatherers were using not only the meat of the owls but also their talons, long bones, and feathers.
Thumb through these reports, and you’ll find that owls are indeed imbued with all kinds of meanings—they’re creators, healers, guides, and guardians, as well as fearful, devilish presences, harbingers of doom and death.
If the gods took their wings from owls, so did the devils. In many cultures, owls are leagued with witches and malevolent spirits, with sorcery and death. “Human fear of owls is common in every part of the world,” says Johnson. “The form it takes may vary from culture to culture, but there are patterns that pop up, consistent beliefs and narratives in different versions.”
If an owl perches on top of your house in Zambia, you will receive bad news or there will soon be a funeral, and if one sits in your farm fields, your crops won’t grow.
When researchers in Zambia asked children to write what they knew about owls from stories passed down in their families, witchery was a common theme, especially owls as a means of transport by people who practice witchcraft.
The point is, few animals have such an immensely ambivalent and complex relationship with humankind. From folklore to art, they’ve been revered and reviled, deemed sage and stupid, coupled with destructive witchcraft and with healing. Sometimes they symbolize two opposing things at once. And sometimes they’re just . . . birds.
Here’s another example of the newly discovered enigmatic abilities of owls. In 2021, scientists at the Israel Institute of Technology discovered that barn owls build mental maps of their surroundings in a part of the brain called the “hippocampus”—while they’re on the wing.
Although owls in the wild can live up to twenty-five years, most have a much shorter life span. Big owl species live longer than smaller ones.
