The southern cassowary is widely regarded as the world's most dangerous bird to people, and the ostrich can also inflict severe injuries. Many other birds on this list become aggressive when defending nests or young, or after learning to associate people with food.
The risks range from powerful kicks by large flightless birds to swooping attacks around nests. Knowing what provokes these encounters helps you give the birds enough space and enjoy watching them safely.
How we chose these
We chose birds with documented attacks or clear wildlife-agency warnings about injury to people. Cassowaries and ostriches lead for their capacity to inflict severe harm; the remaining numbers are an editorial display order, not a measured ranking of attack frequency or deaths. The focus is direct encounters, including falls caused by defensive attacks, rather than aviation collisions or disease.
10. Red-tailed Hawk
Red-tailed hawks can dive at people who come too close to a nest, striking with their feet and sharp talons. The U.S. Fish and Wildlife Service specifically lists them among raptors that may become aggressive during the nesting season. A hawk circling or calling above a path may be defending young nearby, rather than showing interest in a person as prey.
Their feet are built for gripping animals: Cornell's account of red-tailed hawks describes how they use their talons to capture and kill prey. If a nesting bird repeatedly swoops at you, take another route. The wildlife service recommends avoiding the immediate nest area until the young have fledged; an open umbrella can provide cover when passing through, but should never be used to strike the bird.
9. Snowy Owl
Snowy owls can dive-bomb and strike people approaching their nests. Their white plumage may look soft, but their feet carry the sharp claws of a predator. They nest on the ground in the Arctic tundra, where an approaching person is especially exposed. Cornell describes males defending territory against other snowy owls, and reports defensive attacks on people.
The nest is usually a shallow hollow on a raised patch of ground, giving the adults a view across the surrounding landscape. According to the same Cornell species account, the female makes the hollow by scraping the ground and pressing her body into it. Keep your distance from a nest, and move away if an owl begins making defensive passes instead of staying for a closer photograph.
8. Canada Goose
Canada geese can injure people while defending their nests and goslings. A pair that tolerates walkers at other times may hiss, lower its head or advance when someone approaches its young. Parks, lawns and paths can bring nesting geese close to people, so a familiar setting does not mean a bird will accept close contact.
The harm is not limited to a bite or a wing strike. A U.S. Fish and Wildlife Service assessment records nips, scratches and bruises, as well as fractures caused by falls during encounters. Give a defensive pair room and choose another path if possible. Avoid feeding geese or trying to move their young for a photograph. Canada's wildlife guidance recommends preventing public feeding as one way to reduce conflicts.
7. Barred Owl
Barred owls sometimes swoop at people entering their territory, and their talons can injure an uncovered head. Washington's wildlife agency identifies barred owls as frequent culprits in its reports of territorial owl attacks. Encounters are uncommon, but a quiet wooded path can pass close to a nest or a place the bird is defending.
The Washington Department of Fish and Wildlife reports these incidents in spring and fall, especially at night or around early morning and late evening. An owl may approach with little warning, so repeated swooping is a reason to leave the area. Protect your head and face, and use another route for a while rather than trying to confront or catch the bird.
6. Emu
An emu can kick forcefully when threatened at close range. Australia's tallest native bird can reach about 6.6 feet (2 m) and can run at roughly 31 mph (50 km/h), according to New South Wales wildlife authorities. Its long legs make it a fast runner, but they also allow a cornered bird to defend itself.
Emus generally avoid danger by moving away. Trouble is more likely when people crowd or attempt to handle them. The Northern Territory government's guidance warns that they can peck and kick and should not be treated as harmless pets. Watch from a distance and leave an escape route, especially in an enclosure where the bird has limited room to retreat.
5. Mute Swan
Mute swans can charge at people who approach their nesting territory. Michigan's Department of Natural Resources warns of aggressive encounters involving people on shore and on the water. Their large size and raised wings make the display intimidating, particularly when a walker or small boat comes between a pair and its young.
A tucked neck and wings lifted over the back can signal a defensive bird. Cornell describes swans chasing intruders, including people, away from the nesting area. Give the family space and steer clear of nests when walking or paddling. A swan that seems calm farther out on a lake may behave very differently when guarding eggs or cygnets.
4. Australian Magpie
Australian magpies may swoop at walkers and cyclists during the breeding season to protect eggs and young. Queensland identifies spring, roughly August through November, as its main swooping period. The bird's fast approach can startle someone into falling, while direct contact can cause injury. However, Victoria's wildlife authority notes that contact is rare; many swoops are warning passes.
The simplest precaution is to avoid the nesting area temporarily. Queensland recommends a broad-brimmed hat and sunglasses or an umbrella to protect the face. If a magpie swoops while you are cycling, get off and walk the bike away. Do not throw objects at the bird or approach a fledgling: those actions can strengthen its response to people near the nest.
3. European Herring Gull
European herring gulls can dive at people near nests and chicks, including around rooftops in coastal towns. Food creates another source of conflict: gulls accustomed to being fed may snatch it directly from someone's hand. The species here is Larus argentatus, the European herring gull, recognizable as an adult by its pale gray back and pink legs.
The RSPB advises against feeding gulls and recommends an umbrella when you must pass close to protective parents. Keep food waste secure and give chicks space, including fledglings on the ground that are still being watched by adults. These encounters are usually connected to food or breeding territory; a gull flying overhead is not automatically preparing to attack.
2. Ostrich
An ostrich's forward kick can cause severe injury, making its powerful legs dangerous at close range. It is the largest of the living birds and can run at about 43 mph (70 km/h). Its long legs end in two-toed feet, with a substantial claw on the larger toe. Flight is not an escape option for this bird, but running and kicking are.
A published medical case report describes a man who suffered a serious abdominal injury after entering an ostrich's territory and being kicked. That is a documented example of the damage one encounter can cause, not evidence that attacks are frequent. Give ostriches ample room and follow barriers and staff instructions wherever they are kept, especially around breeding birds.
1. Southern Cassowary
A southern cassowary can deliver a kick with an inner-toe claw about 5 inches (12 cm) long. Its blue neck, red wattles and tall head casque make it one of the most striking-looking birds, but the feet deserve just as much respect. Rare documented fatal attacks include an Australian incident in 1926, after boys and dogs attacked a bird, and a 2019 incident involving a captive cassowary in Florida.
Southern cassowaries may become bold and aggressive after being fed, and males defend their chicks. Queensland's safety guidance says never to feed or approach them, or get between a father and his young. If a bird approaches, remain calm, keep facing it and back away slowly. Put a tree, backpack or other barrier between you and the bird when possible.
