Burrowing Owl Facts
Appearance
• Stand about 9½ inches (23 cm) tall
• Weigh about 150 grams (about as much as a half can of pop)
• Brown feathers with white spots
• No ear tufts
• Bright yellow eyes
• Long, featherless legs
• Adults have speckled chests (males and females are almost identical in appearance), chicks have solid, buffy-coloured chests
• Found on the ground (not in trees)
• Nest underground (if you can see the eggs, it’s not a burrowing owl nest!)
• Closely associated with ground squirrel, badger and prairie dog burrows
Vocalizations
Usually quiet, although they do have several vocalizations:
• mainly during the spring (when calling for mates) they’ll give a “coo-coo” call
• when disturbed, adults give loud, aggressive alarm calls
• when chicks are disturbed in the nest they have an alarm call that sounds like a rattlesnake!
Take a listen here: Burrowing Owl Sounds
Biology & Natural History
Burrowing owls that breed in Canada are migratory, spending their winters in southern Texas and northern Mexico — over 3,400 km away! Each spring they arrive back on their Canadian breeding grounds in mid- to late April.
When the owls arrive, they choose a burrow and territory to their liking. Typically the same areas, and even the same burrows, are used as nests year after year — but not always by the same pair of owls.
Even though they don’t actually dig their own burrows, the owls will bring in nesting material to “spruce the place up”. Their choice of nesting material may raise a few eyebrows — manure! The owls will bring in horse, cow, or buffalo manure (if they can find it) to line their nest chamber and tunnel. It’s thought that the manure acts as an absorbent in heavy rains so the burrow doesn’t flood — but it also provides a nice soft place for the female to lay her eggs! The smell of the manure also helps to mask the smell of the owls themselves, making it harder for predators to detect them and it will also attract insects to the burrow making for a quick and easy snack for the owls!
Did you know . . .
Burrowing owls store their food in their burrows during the spring and early summer (called a cache). One prey cache contained over 200 mice and voles!
The first eggs are usually laid within two weeks of the female’s arrival, and the average clutch size is about 9 eggs. During incubation, the female does all of the incubating while her mate does all of the hunting — not only for himself but for his mate as well!
After the female incubates the eggs for about 28 days, they start to hatch. The chicks are entirely helpless when they first hatch, and depend on their mother for food and warmth.
This is a critical period for the young owls: if there isn’t enough food to feed them all, the younger chicks may be killed and fed to their older siblings! While it may seem cruel, this is nature’s way of ensuring that at least some of the young owlets survive.
For about the first two weeks, the young chicks will remain inside their nest burrow, under the warmth and protection of their mother. At about 2-3 weeks of age, the young owlets start to explore the world outside their nest burrow for the very first time. At 3-4 weeks, they start to wander away from their nest to explore other burrows in the immediate vicinity. By the time they’re 4-5 weeks old, the young owls can fly and begin to hunt things like insects on their own.
At about 6 weeks of age, the chicks are considered to have fledged. Even though they are becoming more and more independent from their parents, there are still many dangers for the young owls to face. The first few weeks after fledging is one of the most perilous times for young burrowing owls — in fact, almost 45% of the chicks that fledge will not live long enough to migrate for the first time.
Beginning in September, the owls from Saskatchewan start their long migration to southern Texas and northern Mexico for the winter. Sadly, we can only expect to see 1 in 20 of the chicks born in Saskatchewan ever again. It’s not known if they’re dying or just dispersing to other areas and not returning to Saskatchewan.
Distribution in North America
Burrowing owls inhabit prairie grasslands, steppes, deserts and arid areas throughout western North America.
Their distribution in North America has decreased considerably in the past few decades, especially in the northern and eastern portions of their range.
Burrowing owls are no longer found in the wild in Manitoba (they have been extirpated from the province), and their populations continue to decline in Saskatchewan and Alberta. Through an extensive breed and release program, Burrowing Owls have been reintroduced into the interior of British Columbia thanks to the hard work and dedication of Burrowing Owl Conservation Society of BC.
Burrowing owls don’t dig their own burrows, so they have to rely on other animals to do it for them. Throughout much of their range in the United States, the owls nest in prairie dog towns. In Canada, prairie dogs are only found in and around Grasslands National Park in the southwest corner of Saskatchewan. In the rest of their range in Canada and the U.S., the owls use the abandoned burrows of animals such as ground squirrels (also called gophers) and badgers as nests.
Problems Facing the Burrowing Owl
Why are burrowing owls endangered?
Burrowing owls are in trouble. Biologists who have monitored their population around Regina, Saskatchewan for more than a decade have recorded a population trend that points straight down; over the past 10 years, we have been loosing burrowing owls at a rate of about 22% per year! The same trend is apparent to landowners who voluntarily report their sightings of burrowing owls on their land to Operation Burrowing Owl.
Unfortunately, there doesn’t appear to be just one cause for the burrowing owls’ decline, and there certainly doesn’t look like there is an easy solution to the problem. Several factors likely contribute to varying degrees, and several stages of the burrowing owls’ life are probably affected.
We’ve described a few of the more likely problems below, but this is certainly not a complete list. We’ve divided the potential problems into three broad categories — lack of space (habitat loss), low birth rate (low productivity) and high death rate (high mortality).
The information presented here comes from the hard work and dedication of biologists, volunteers, and landowners who are all doing their best to try to help the burrowing owl.
Habitat Loss
As with many endangered species, one of the main problems facing burrowing owls today is the loss of habitat (the land and resources) that they need to survive.
Burrowing owls live in open grassland areas in western North America. In Canada they are currently restricted to the southern areas of Saskatchewan and Alberta. Since the early 1900s, much of the western Canadian prairie has been cultivated for agriculture, especially here in Saskatchewan.
Agricultural crops don’t provide the habitat that burrowing owls require, so the owls are restricted to the small fragments of prairie that remain as cattle pastures. In much of southern Saskatchewan, these small cattle pastures are the last remaining refuge for burrowing owls. The horses and cattle are beneficial to the owls, as they keep the grass short by grazing and provide nest-lining material (manure!) for the owls.
In addition to grasslands, burrowing owls also need burrows to nest in. Since they don’t dig their own burrows, they must rely on animals like prairie dogs, badgers, and ground squirrels (also known as gophers) to dig holes for them. Unfortunately, these animals are often seen as pests and are killed — sometimes with poisons that could just as easily kill the owls. If too many of these burrow-providing animals are lost, there will be no place for burrowing owls to live. In the United States, 99% of the prairie dogs have been exterminated. Considering how fundamentally important prairie dogs are to burrowing owls (because of the burrows they provide), it’s not difficult to see how that could be extremely detrimental to the owls.
Did you know . . .Ground squirrels (gophers) are not only essential for burrowing owls but for many other prairie residents as well. They are considered “keystone species” because of their importance at many levels of the prairie ecosystem. To learn more about ground squirrels from an expert in Lethbridge, AB, click on the picture to the left.
Low Reproduction
Like any other species, burrowing owls need food to survive and raise their chicks. If not enough food is available to them, they will not be able to raise as many chicks as they would if food was plentiful. Click on the thumbnail below to see the chicks and their pantry of food.
Burrowing owls are a generalist predator, which means that they will hunt and eat almost anything that’s small enough for them to catch. Here in Canada, their diet consists mainly of small mammals (mice and voles) and insects (grasshoppers, beetles, etc.). But they’ve been known to eat everything from birds to snakes to salamanders.
Recently, biologists have found that by providing supplemental food to the owls during the period when the chicks are young, the owls were able to raise a larger family than they would have without receiving the extra food. This suggests that there may not be enough food naturally available in the environment for the owls to be able to maximize their families.
It’s always important to look at the big picture. No matter what we do to try to help the owls themselves, we won’t be successful unless we consider that they are a part of a larger ecosystem, and that things that affect other members of that ecosystem will affect the owls as well. If there is not enough food for the owls because a prey population is in trouble, burrowing owls will feel the effects.
High Mortality
Although burrowing owls are predators, they are not at the top of the prairie food chain, which means that they are also in danger of becoming prey for other predatory species. Larger owls, hawks, coyotes, foxes, weasels, and badgers all naturally prey on burrowing owls. However, domestic dogs and cats have also been known to make a meal out of unsuspecting burrowing owls.
Fast Facts . . .Pet cats that are allowed to wander freely outside are responsible for the death of more than a billion birds in North America each year! Cats are not naturally found in the prairie landscape, and they can have a devastating effect on native wildlife, including the burrowing owl. Please — keep your cats indoors. They’ll live longer, and you’ll be protecting wildlife.
Juvenile burrowing owls are the hardest hit by predators on the breeding grounds. Biologists have discovered that as many as 45% of all juvenile owls that survive long enough to fledge may be killed before they migrate south
for the first time. In an average owl family of 4 chicks, that means that only 2 may survive long enough to begin migration.
There are a number of reported causes of mortality for burrowing owls on the breeding grounds. They have been killed and eaten by other predators, they have starved to death because food was in short supply, they have been hit by vehicles on country roads, they have become entangled in barbed-wire fences, and they have been accidentally shot because they resemble gophers.
One issue that is currently being investigated is whether or not pesticides may be causing a problem for burrowing owls. The owls may be coming into contact with the pesticides indirectly, as they eat infected food (like mice, grasshoppers and gophers).
A rather ironic twist to the burrowing owl story is that while they are occasionally killed and eaten by badgers, burrowing owls could not exist in Canada without them. Since prairie dogs (the animals that burrowing owls rely on throughout most of the US) are naturally restricted to only a small area in the southwest corner of Saskatchewan, the main burrow provider for burrowing owls throughout the Canadian prairies is the badger. The badger’s main source of food is ground squirrels, and occasionally burrowing owls are just in the wrong burrow at the wrong time!