This is the largest of all Eocene birds, Gastornis, a half-ton pile of muscle and feather as tall as a grown man.
— Allen, about Gastornis

Gastornis (name meaning "Gaston's Bird"), also known as Diatryma, is a genus of large flightless bird of prey that originated during the Late Paleocene epoch in what is now Europe and North America. Standing 2 meters tall and weighing half a ton, Gastornis was the apex predator of its time.

In the Series 3 premiere, a pair of Gastornis, male and female, were saved from poisonous gas and brought back from the Early Eocene of 50 million years ago. The pair reside in a heavily-forested enclosure.


Era & DiscoveryEdit

Gastornis lived in North America and Europe during the Paleocene to Eocene epoch, from 56–45 million years ago. It was the apex predator of its time and shared its environment with creatures such as Propalaeotherium, Leptictidium, and Ambulocetus. Gastornis died out at the end of the Eocene when larger mammalian predators, such as Hyaenodon, evolved.

Gastornis was first described in 1855 from a fragmentary skeleton. It was named after Gaston Planté, described as a "studious young man full of zeal", who had discovered the first fossils in Argile Plastique formation deposits at Meudon near Paris.

Physical AttributesEdit

The largest of all predatory Eocene birds, Gastornis stood about 6 feet (2 m) tall, as tall as a grown human, and weighed 1000 lbs., making them the second largest flightless bird ever to exist, after the Pleistocene Terror Birds Phorusrhacos. Smaller but more robust than Phorusrhacos, Gastornis were large, fairly thickly-built birds with heavy, stocky heads and a 45 cm skull and beak, shaped like a hatchet. The beak, although very large, was not hooked like with other terror birds such as Phorusrhacos

Although Gastornis was the biggest land creature of its time, it had a relatively short neck and thick legs, as opposed to terror birds of later times; in fact, despite the superficial similarities, Gastornis' closest relatives were ducks and chickens, while the terror birds (phorusracids) are actually closely related to cranes, seriemas, etc.

Gastornis feathers came in a variety of bright colors; most individuals had cream undersides and turquoise to green bodies. The skin around their faces was red and wrinkly. Although the wings - and companion feathers - of Gastornis were underdeveloped, similar to trimmed chicken wings, they were still better developed than those of Phorusrhacos.

Gastornis, much like Phorusrhacos, also had crests of colored plumage on the back of their heads. This plumage was duller and less apparent than on the Phorusrhacos.

Behavior & TraitsEdit

1000px-WWB1x1 GastornisCheckingEgg

Female Gastornis with an egg

Gastornis were solitary creatures, only getting together during mating season. Gastornis was most likely an ambush predator, lying in wait to attack animals like Propalaeotherium. When female Gastornis laid eggs, the had to wait two months for them to hatch. These birds were also fiercely territorial and when another Gastornis (whether it be male or female) got to close, the mothers moved to protect their nest.

Since the great extinction of the dinosaurs, birds like Gastornis had been a success like all mammals but, what was more, they grew large – enough so to take over the role of the predatory dinosaurs, from as small as the lethal Velociraptors to as giant as even the terrifying Tyrannosaurus.



  • Gastornis is the second largest flightless bird brought to the park.
  • Strangely, it's been questioned whether Gastornis was a herbivore, carnivore, or even an omnivore.
  • The sound effects of Gastornis are typical bird chirps as well as vulture sounds.
Community content is available under CC-BY-SA unless otherwise noted.