Ornithomimus, which means "bird mimic". And you can see why; exactly like an Ostrich.
— Allen, about Ornithomimus
in Dinobirds

Ornithomimus (name meaning "Bird Mimic") is a genus of omnivorous ornithomimid theropod dinosaur that originated during the Late Cretaceous period in what is now North America. Ornithomimus appear to be flock animals whose chicks possessed fluffy feathers and (like many modern-day birds) imprint on the first thing they see.

Herd living prey for animals like Tyrannosaurus, Ornithomimus was among the last of the dinosaurs. A rare herbivorous theropod, they fed on both terrestrial vegetation and aquatic particles.


Era & DiscoveryEdit

Ornithomimus lived during the Late Cretaceous period from 75–65 million years ago. It died out with other dinosaurs at the end of the Cretaceous. They were also prey items for predatory dinosaurs like Tyrannosaurus and Dromaeosaurus. Ornithomimus was discovered and named by Othniel Charles Marsh in 1890.

Physical AttributesEdit

1x1 OrnithomimusEmergesFromBush

To the tip of its snout, Ornithomimus stood 7 feet (2.1 m) tall, measured 12–15 feet (3.7–4.7 m) long and weighed 167 kg (370 lbs). These dinosaurs were vegetarians, but they would occasionally eat meat, therefore, making them omnivorous dinosaurs; eating plants, meat, small reptiles and mammals, and even eggs. They were utterly the opposite of what anyone would imagine what dinosaurs to be like. Ornithomimus chicks were covered in downy feathers which would molt by adulthood.

With their beaks at the front, they had ridges on the inside, much like modern ducks and geese, and Ornithomimus used those to crush their food. The beaks on these creatures allow then to sieve their food, making them more like ducks than ostriches. The males also looked different from the females, with the males having a blue body appearance and the females being more grey in color.

In addition, Ornithomimus was a very fast, swift, and agile animal, capable of reaching speeds as fast as 40 mph, as fast as an Ostrich.

Behavior & TraitsEdit

1000px-1x3 OrnithomimusCheckingOnEggs
Like many dinosaurs of their size and overall appearance, Ornithomimus was a highly social omnivore that lived in flocks of around 13 to 20 individuals. Despite the vast numbers of individuals in a flock, they would still flee from danger. 

In addition, whenever they were brooding, the female Ornithomimus would distance themselves, breaking off from the rest of the flock to make a nest. Ornithomimus females were also very protective of their eggs and would lay around ten eggs but the mother would sacrifice at least two eggs to feed predators.

Despite their close resemblance to ostriches, Ornithomimus behaved more like ducks. They preferred to live near lakes and ponds rather than forests or open plains. In fact, their mouths had the texture of sandpaper and were used more like sieves than beaks.



  • The sound effects of Ornithomimus are that of a donkey, elk, duck, and geese as well as flamingo, emu, and ostrich.
  • Ornithomimus is the only ornithomimid dinosaur brought into the park.
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