The Three Flightless Birds Of Power

By Emma Caplan on June 22 2020 in Environment

Two emus walking on a road. Image credit: Deb talan/
  • Cassowaries attack up to 200 people each year and can kill, but only if provoked.
  • Male ostriches are the largest birds, standing up to 9 feet tall and weighing over 330 pounds.
  • Emus run very fast and kick with three-toed feet.
  • All of these birds have toe claws that can disembowel animals, but it is rare that they kill humans.

With at least 9,000-10,000 species of birds in the world, it is hard to know which types you might come across. While all birds are generally harmless and blend into our daily outdoor lives, defending their territory and young is instinctive and a very normal part of nature for all types of birds. When it comes to particularly aggressive birds, injuries and even deaths can happen. Below are three birds that are large and powerful and equipped by nature with defences that kind of make up for their inability to fly. 


A southern cassowary. Image credit: Torsten Pursche/

Cassowaries are related to emus (more on them, below) and live throughout parts of Australia and New Guinea. They move quickly along narrow tracks in the bush, running as fast as 31 miles per hour, and they can jump nearly 7 feet high. Standing over 5 feet tall, the heaviest females can weigh more than 160 pounds and males weigh up to 120 pounds.

When threatened, this bird kicks with its strong, powerful legs. It has been known to kill humans with slashing blows of its feet - the innermost of its three toes has a long daggerlike nail that can be 5 inches long. 

    Cassowaries are curious and will sometimes attack, though human attacks are pretty rare and mostly involve taking food from people. These birds are capable of leaving lethal wounds on internal human organs causing severe bleeding. 

    Cassowaries attack up to 200 people each year, especially if people approach them with food, but, thankfully, they will not attack unless provoked. Though shy and confrontation avoidant where possible, these birds will still use self defense as they are territorial and protective of their young.

    The claws of the cassowary. Image credit: Vladimir Wrangel/

    In 2019 in Florida, the owner of a cassowary and breeder of the birds died after he fell in his backyard and his bird attacked him.

      In 2012, a cassowary kicked a tourist in Queensland, Australia off a ledge into a body of water (they were unharmed).

      In 1926, a teenage boy hunting cassowaries in a group was laying on the ground and killed after a cassowary jumped on him, slashing the boy’s jugular vein with its toenail.


      The strong legs of an ostrich are its biggest weapon. Image credit: Ekkachai/

      Ostriches live in the African open country. They are the largest living birds, with adult males standing up to about 9 feet tall and weighing more than 330 pounds. These birds spend time individually, in pairs, in small flocks, or in large groups, depending on the season.

      The ostrich relies on its two-toed strong legs to escape its enemies, mainly humans and large carnivores. A frightened ostrich can run 45 miles per hour. Its kick is so forceful that the bird can kill lions and other large predators (however, this is rare as most attacks result from humans provoking the birds).

      The American musician, Johnny Cash, kept an exotic animal park with ostriches on his property. In 1981, he repeatedly found an aggressive male ostrich during his walks in the park. During one of these instances, the musician took a 6-foot stick and swung it at the bird, who dodged and then slashed at him with its foot. Cash recalled that the blow struck him in the stomach, and if it were not for a strong belt buckle, the ostrich’s toe claw would have cut his abdomen open and killed him.


      Emus at the Pinnacles Desert, WA, Australia. Image credit: mcography/

      Emus are stout-bodied and long-legged, just like their cassowary relatives. After the ostrich, they are the second-largest living bird, standing over 5 feet tall and weighing about 100 pounds.

      Though they do not fly, emus run very fast at a speed of almost 30 miles per hour. If cornered, they kick with their big three-toed feet. Just like cassowaries and ostriches, their toe claws can disembowel animals, but it is rare that they kill humans.

      Emus can be very gentle, but, like most wild animals, they will occasionally behave in unexpected ways. In Australia and throughout various parks, zoos, and farms worldwide, many injuries have been reported to be caused by emus.

      In 2019 at a zoo in Adelaide, Australia, a zookeeper suffered injuries to her face and arms by an emu while feeding it.

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