Boreal Owl

Aegolius funereus
Population status:
Least Concern
Body length:
8-11in (22–27cm)
Wingspan:
20-24in (50–62cm)
Weight:
3-7oz (85-198g)

Ed MacKerrow

Did you know?

  • The Boreal Owl doesn't have a very long life, living only to be 7 or 8 years old.
  • If you have read through our Explore Raptor pages, you probably already know that in general, female raptors are larger than the males of the same species. This is unmistakable in the Boreal Owl. Females are obviously larger than their male counterparts. According to the Cornell Lab of Ornithology, it "shows the most extreme reversed sexual dimorphism of any American owl."
  • Boreal Owls can vary a bit in coloration, ranging from grayish to rusty brown.

Other Owls

How The Peregrine Fund is helping

The Peregrine Fund is not working directly with Boreal Owls, but our conservation efforts through habitat protection, education, and community outreach extend to all raptor species, including this adorable owl. We have founded the Tundra Conservation Network to connect scientists working to conserve tundra habitats around the northern hemisphere. We also supply literature to researchers from our avian research library, which helps scientists around the world gather and share important information on raptor conservation.

 

Where they live

Boreal Owls are circumpolar, which simply means they are found near one of Earth's poles. In this case, that pole is the North Pole. Boreal Owls make their home in the northern reaches of North America, including Alaska and Canada and the northern regions of Eurasia. This small owl can also be found in some mountain ranges further south, such as the Rocky Mountains in the western United States and northern Minnesota.

As its name suggests, the Boreal Owl prefers boreal or montane, decidious forest habitats, which are carpeted with tall trees such as pine, birch and spruce. The Boreal owl enjoys roosting in dense coniferous trees that offer protection from inclement weather and make them harder for predators to see and capture.

 

What they do

The Boreal Owl certainly ranks among the world's cutest owls. Less than a foot tall, it is a rather smallish owl with large yellow eyes, a chocolately brown body with white mottling, dark feathers which line its facial disk, and white spots on its head. If the adult Boreal Owls are cute, the juveniles are irresistibly so! Covered in fluffy greyish feathers, they have darker feathers around their yellow eyes and white "eye brows."

Like other owls, the ends of the Boreal Owl's flight feathers are very soft and, well... feathery, giving it the ability to fly in absolute silence, because the air doesn't make noise as it passes through the soft feathers. This helps them be very stealthy hunters. Since they often fly low over the ground when hunting, it is important that their prey doesn't hear them coming!

Many owls use their exceptional hearing to help them locate prey, and Boreal Owls are no different. Though they use their keen eyesight to find tasty morsels of food, they live in areas where the ground is often covered in snow. When this is the case, many small mammals move around by tunneling their way beneath the snow unseen. So, what is an owl to do? You guessed it. The Boreal Owl uses its sharp hearing to pinpoint exactly where prey is moving. Owls can detect a vole's exact location, pounce down and grab it out of the snow without ever once laying eyes on it! The little rodent, of course, never sees it coming.

Boreal Owls are not normally migratory, though some populations will move south in colder months. Similar to the Snowy Owl, they will also occasionally irrupt. Don't worry, this doesn't mean that they spew lava like a volcano. Irrupt (instead of erupt) means that they head south beyond their range, normally in search of food.

 

Why they need our help

Because of their naturally shy nature and their remote habitat preferences, Boreal Owls can be hard to study. Therefore, not much is known about them compared to all that we know about Great-horned Owls, so scientists don't have precise population numbers. However, because they rely on mature and dead trees for nesting, habitat loss is a very real threat for the species. The species is generally considered to be uncommon.

Natural predators for this species include other larger owls, large diurnal raptors such as Goshawks, and mammals such as Pine Martens.

 

What they eat

Borreal Owls tend to hunt from a stationary position, watching for prey from a strategic perch. When they find something that looks good to eat, they will pounce on their prey, grabbing and killing it with their feet. Though their food of choice is voles, they will also eat just about anything that is catchable and the right size such as: mice, moles and shrews, bushy-tailed squirrels, swooping bats, small amphibians, other birds, and crunchy beetles.

Generally speaking, the Boreal Owl is strictly nocturnal, meaning it is active only during the night and rests during the day. However, during the 24-hour light during the summer at the northern extent of their range, this small owl has no choice but to go about its hunting during the day.

 

Nest, eggs and young

The Boreal Owl has some interesting breeding behavior. Similar to the Galapagos Hawk, the Boreal Owl can be polyandrous (meaning the female will breed with 2 or more males in the same breeding season). However, this isn't always the case. In fact, this species may be monogamous (meaning 1 male and 1 female remain together for the entire breeding season), polygynous (where 1 male breeds with 2 or more females in the same breeding season) or, as mentioned above, polyandrous. Scientists think that this breeding behavior is influenced by the availability of prey. When there are lots of small mammals around, the owls tend to shy away from monogamy. Scientists believe this is because so much food is available, it is easy for one lone parent to find enough food to feed its young. Boreal Owls usually form pair bonds that last only during one breeding season.

Boreal Owls do not build stick nests. Instead, they will occupy old woodpecker holes or other natural tree cavities, laying their eggs on the natural substrate within these holes. Like the American Kestrel, Boreal Owls will also use man-made nesting boxes with relative frequency. If you live in Boreal Owl habitat and would like to have a pair nesting near you, try installing a nest box somewhere in your backyard. If you are interested, follow this link to learn more.

There is a saying that "the way to a person's heart is through food," and the Boreal Owl takes this saying very seriously. After the male locates a nesting cavity that he finds suitable, he then needs to find a female he also likes. To gain her attention and her affection, he will leave food inside the potential nesting cavity. If the female likes the nesting spot and the food, she will stick around.

When it is time, the female will lay between 3-6 eggs. But as mentioned, when prey numbers are high, they tend to have more young. In fact, during high prey years, they may lay more eggs per clutch or have more than one clutch in a season. The female is responsible for incubating the eggs, and they must be incubated for about a month. During this time, the male will bring her food. When the chicks hatch, they are very fluffy and downy and don't open their eyes for the first time until they are over a week old. But they will begin to grow quickly. After only about 5 weeks, the young will fledge. After another month or two, the young will become independent of their parents' care - this means they are good enough at hunting that they can catch all the food they need on their own. It also means they are responsible for evading danger, such as predators, without their parents' help. When they are only one year old, they are able to reproduce and become parents themselves!

 

Idaho Connection

According to the Idaho Fish and Game Department, the Boreal Owl has only been a documented resident in Idaho since the 1980's. They believe it was likely present from long before that, but just hadn't been detected because of its shy nature and the fact that it can live in forests which are harder to access. Since then, their biologists have found this species breeding in several counties throughout the state and have documented individuals in many of Idaho's national forests.

In Idaho, this species is considered a species of "great conservation need," because of increased habitat loss due to logging and, more specifically, clear-cutting.

Boreal Owl and The World Center for Birds of Prey

The visitor center at The Peregrine Fund's World Center for Birds of Prey includes owls among its avian ambassadors. This is a great chance to see owls up close and learn about the wonderful and interesting adaptations they have in order to survive in their respective habitats. There is also a touch table with owl feathers and other natural objects available for exploration.