Owls are skilled hunters, but they are some of the least handy builders in the bird world. Most don’t build a nest at all. They move into a home that another animal made or that nature left behind.1Birds of the World. Do Owls Build Nests? The Truth About Their Nesting Habits That makes an owl’s nesting less about construction and more about finding the right spot first and then defending it.
Why Owls Don’t Build Their Own Nests
Many birds weave nests with their beaks and feet, but owls have neither the instinct nor the dexterity for it.2Birdfact. Do Owls Build Nests? The Truth About Their Nesting Habits An owl’s hooked beak is shaped for tearing meat, not for handling grass or twigs.3Birdfact. Do Owls Build Nests? The Truth About Their Nesting Habits Their feet carry sharp talons meant for gripping prey. Those talons close in a tight grip that crushes and holds, which is the opposite of the fine pinching and threading weaving needs.
For weeks before egg-laying, a pair inspects candidate sites, such as an old hawk nest, a hollow, or a ledge, rather than gathering material. Once a site is chosen, the female may rearrange what is already there a little, but she brings in almost nothing new. Eggs are often laid straight onto old sticks, wood debris, or bare floor. Owls often start breeding in late winter, before many other birds, when old nests already stand empty.
Borrowed Stick Nests and Tree Holes
Great horned owls don’t build nests and usually take over old hawk nests.4Virginia Department of Wildlife Resources. Techniques for Locating Great-Horned Owl and Hawk Nests These are most often former red-tailed hawk nests, though great horned owls also use trees, caves, cliffs and even old buildings.5Hawk Mountain. Great-horned Owl Owls also reuse nests of crows, ravens, herons and squirrels, so nest size varies a lot.6Birds of the World. Do Owls Build Nests? The Truth About Their Nesting Habits Long-eared owls nest in old crow-family nests in both evergreen and leafy trees.7Journal of Avian Biology. Nest site selection and predation driven despotic distribution of breeding long‐eared owls Asio otus
Hawk and crow nests suit big owls because they are broad, sturdy platforms of sticks, large enough to hold an owl and its growing chicks. They sit high in trees, which keeps eggs and young away from most ground predators. The owl usually just settles in and lays eggs, without rebuilding or lining it. Squirrel nests are bulky balls of leaves and twigs, so whether an owl can use one depends on how big and sturdy it is.
In winter, a borrowed stick nest is easy to spot: look for a big bundle of sticks high in a bare tree. An owl’s ear tufts or tail may poke over the rim. White droppings and pellets on the ground below hint that the nest is in use. Watch from a distance with binoculars.
Other owls depend on tree holes, called cavities, which they can’t dig themselves.8Forest Ecology and Management. Habitat choice of a secondary cavity user indicates higher avoidance of disturbed habitat during breeding than during food-hoarding Owls such as the pygmy owl need a ready-made cavity to breed at all.9Forest Ecology and Management. Habitat choice of a secondary cavity user indicates higher avoidance of disturbed habitat during breeding than during food-hoarding Holes in dead trees serve as nesting cavities for owls along with raccoons, squirrels and wood ducks.10National Wildlife Federation. Turning Deadwood into Homes for Wildlife
Those holes take years to form, as woodpeckers excavate and rot softens the wood. Removing every dead tree removes future owl homes. If a dead tree isn’t near a house or path, it can often stay, and leaving a safe one standing can give owls a place to nest.
Owls can lose holes to other animals.11Animal Conservation. ‘The early bird catches the nest’: possible competition between scops owls and ring‐necked parakeets In one case, invasive parakeets started breeding early and claimed cavities before scops owls returned from migration.12Animal Conservation. ‘The early bird catches the nest’: possible competition between scops owls and ring‐necked parakeets Owls pushed out of good holes may settle in poorer habitat.13Animal Conservation. ‘The early bird catches the nest’: possible competition between scops owls and ring‐necked parakeets
Owls That Nest on the Ground or Underground
Snowy owls nest right on open tundra ground.14Cornell Lab of Ornithology. Snowy Owl The female scrapes a shallow hollow and shapes it by pressing her body into it.15Cornell Lab of Ornithology. Snowy Owl Because her body shapes it, it fits her closely and holds the eggs in place against the wind. This is about as close to building as owls get.
The setting explains the choice. Arctic tundra has few trees, so there are no hawk nests or tree holes to borrow. Snowy owls prefer slight windswept rises that stay dry and free of snow.16Cornell Lab of Ornithology. Snowy Owl A raised spot also lets the female watch for approaching predators from far off.
Burrowing owls nest in underground burrows, often an old one dug by a ground squirrel or prairie dog. They routinely collect dry mammal dung and scatter it in the nest chamber, the tunnel, and around the entrance.17Animal Behaviour. Use of mammal manure by nesting burrowing owls: a test of four functional hypotheses Grass and dung are the most common materials found at their nests.18USGS. Collection of mammal manure and other Debris by nesting Burrowing Owls Why they do it is still debated.
Barn Owls and Nests in Human Buildings
Where hollow trees are scarce, barn owls nest in old barns, silos and grain stores.19University of Missouri Extension. Attracting Barn Owls to Your Property In America they use barn lofts, church steeples, houses, haystacks and even drive-in movie screens.20Birds of the World. Do Owls Build Nests? The Truth About Their Nesting Habits Today many barn owls nest in nest boxes in farm buildings, on trees or on poles.21The Barn Owl Trust. Barn Owl roosting and nesting places Churches, chimneys, bridges and old factories are used less often.22The Barn Owl Trust. Barn Owl roosting and nesting places
A barn suits a barn owl because its natural home is a hollow in a tree, and a dark, sheltered loft or silo offers a similar space. Barns and grain stores also attract mice and rats, the owls’ prey, so food is close to the nest.
Instead of a lining, a barn owl site fills with coughed-up pellets of fur and bones.23The Barn Owl Trust. Barn Owl Pellet Analysis and Dissection – Barn Owl Trust Moths eat the fur over time, leaving tiny bones that last for years.24The Barn Owl Trust. Barn Owl Pellet Analysis and Dissection – Barn Owl Trust
To tell whether owls use a barn or shed, look beneath beams and ledges for gray, thumb-sized pellets. White streaks of droppings on walls or floors suggest an owl roosts or nests there regularly. At night, chicks can be heard hissing or screeching, which gives away an active nest.
Check for owls before renovating an old building or sealing openings. Disturbing an active nest can cause it to fail, and owls are legally protected in many countries, so ask wildlife officials first.
How Owls Choose and Defend a Nest Site
Comfort matters. Spotted owls in hot areas pick nest spots that are cooler than the surrounding forest, which helps them lose less water in the heat.25The Southwestern Naturalist. Thermal regimes of Mexican spotted owl nest stands In cold, windy weather, tree-hole nests keep chicks warmer than open platform nests.26PubMed Central. Potential Influences of Climate and Nest Structure on Spotted Owl Reproductive Success: A Biophysical Approach In mild weather the difference is small.27PubMed Central. Potential Influences of Climate and Nest Structure on Spotted Owl Reproductive Success: A Biophysical Approach
Many owls come back to a good site. In flammulated owls, most males hold one territory their whole breeding lives.28The Auk. Return rate, fidelity, and dispersal in a breeding population of flammulated owls (Otus flammeolus) Females are less loyal, returning about half the time versus over 9 in 10 males.29The Auk. Return rate, fidelity, and dispersal in a breeding population of flammulated owls (Otus flammeolus) A nest used once may be used again, so leave known nest trees and boxes in place and watch the same spot each late winter.
Burrowing owls shift from retreating to confronting intruders once eggs hatch.30Canadian Journal of Zoology. Nest stage, wind speed, and air temperature affect the nest defence behaviours of burrowing owls Ural owl mothers that defend fiercely raise more young that survive to breed.31Behavioral Ecology. Aggressive Ural owl mothers recruit more offspring
That has consequences for people nearby. Owls guarding a nest or newly fledged young may swoop at someone who comes close, often at night, when they are hard to see coming. Wearing a hat lowers the risk of injury from talons, and avoiding the area for a few weeks is safer still. Young owls often leave the nest before they can fly well, so a chick on the ground is usually not abandoned. Its parents may still be nearby and defensive, so keep pets away.
Some owls get help with housekeeping. Eastern screech owls carry live blind snakes to their nests.32PubMed. Live blind snakes (Leptotyphlops dulcis) in eastern screech owl (Otus asio) nests: a novel commensalism The snakes eat insect larvae in the nest debris.33PubMed. Live blind snakes (Leptotyphlops dulcis) in eastern screech owl (Otus asio) nests: a novel commensalism Chicks in nests with snakes grow faster and die less often.34PubMed. Live blind snakes (Leptotyphlops dulcis) in eastern screech owl (Otus asio) nests: a novel commensalism
How to Help Owls Nest Near You
Owls that nest in tree holes readily use boxes that resemble them.35Forest Ecology and Management. Habitat choice of a secondary cavity user indicates higher avoidance of disturbed habitat during breeding than during food-hoarding Box design, surroundings and land use all affect whether barn owls move in and breed well.36The Journal of Wildlife Management. Barn owl site occupancy and breeding success in relation to land use and nest box characteristics So match the box to the local owl species: screech owl boxes are small, and barn owl boxes are far larger.
Mount the box high on a pole, a tree, or a barn wall, facing open ground where the owls can hunt. Put a few wood shavings in the bottom, since owls bring no lining of their own. Install it before breeding season, which can start in late winter, so owls can find it in time.
Once a box is up, leave it alone. Checking nests can stress owls.37SouthTexasNews.com. Researchers have developed a way to count hidden baby barn owls from a distance by using AI and sound Watch from afar rather than opening the box during breeding.
Boxes aren’t the only help. Keep dead trees where they are safe, leave grassy fields where owls hunt, and avoid rat poisons, which can harm owls that eat poisoned rodents.