Length: 15 feet
Height: 5 feet
Weight: 150 pounds
- Male: A distinct bright red color, especially on the back, and have pale yellow underbellies and markings on their flanks.
- Female and juvenile (both sexes): Like the male, only with a more orange color instead of red and pale yellow backs.
Length: 15 feet
Height: 5 feet
Weight: 250 pounds
- Adults and juveniles (both sexes): A dark but faded red with crimson to black blotches along the body, with a white underbelly.
The Herrerasaurs on Nublar have a far different color pattern than those on Sorna. This may be either due to genetic selection by InGen to produce more vibrant colors; or the Nublar variant is a different subspecies entirely.
Diet: Carrion, eggs, baby dinosaurs, tree-dwelling animals such as birds, monkeys, sloths and ocelots.
Preferred Habitat: Dense jungle and forest. On Nublar, groups of Herrerasaurus favour the ruins of the Bone Crusher roller coaster.
Social Structure: Usually in male/ female pairs, occasionly small groups.
Herrerasaurus is among the most prehistoric of Nublar and Sorna's dinosaur species, yet at the same time it is surprisingly advanced. It has a flexible, hinged joint in its lower jaw which allows it to get a good grip on its struggling prey. Its most primitive feature are its hands. Each hand has five fingers instead of the usual three seen in other, more advanced theropods. The first two fingers and the thumb possess curved, sharp claws for grasping prey and clinging to branches. Its fourth and fifth digits are just small stubs without claws.
Not including Archaeopteryx, Herrerasaurus is one of two truly arboreal dinosaurs cloned by InGen (the other being Sinornithosaurus), and it is as much at home in the trees as Velociraptors are on the ground. Herrerasaurus itself rarely ventures onto the ground unless tempted by food or when the next tree is too far away to jump. Like a clouded leopard, Herrerasaurus’ ankles can rotate a full 180 degrees, allowing it to run straight down a tree. Its tail lacks stiffening rods and thus it is incredibly flexible. It is in fact prehensile, much like that of a chameleon. Using its tail like a fifth limb, it can spring through the jungle canopy nearly as fast as the raptors can run along the forest floor. Its flexible body allows it to take up residence in the densest of thickets, slip through the smallest gaps in branches, and even turn around at pursuing predators for a quick defensive snap. Its tree-dwelling habits also allow it to consume its kills high off the ground, where no other predators can reach.
Yet another aspect of Herrerasaurus' unique lifestyle are its nesting habits. Rather than laying eggs in a nest on the forest floor, Herrerasaurus nest in the highest tops of trees on the farthest, thinnest branches they can reach; far away from any would-be egg thieves. Being rather monogamous, both parents take turns guarding the nests while the other hunts for food.
Herrerasaurus’ cackling call is unique among theropods, sounding like a sharper version of the hyena's laugh.
Similar to Indian jackals with tigers, some Herrerasaurus become attached to lone Ceratosaurus and Metriacanthosaurus. The Herrerasaurus help dispose of carcasses quicker while also providing an elevated vantage point to scope out potential prey or oncoming predators. In return, the larger carnivore allows the Herrerasaurus to eat off of its kills; and provide protection from threats.
Herrerasaurus bites are surprisingly strong for its size. Small prey are snatched in the dinosaur's grasping clawed hands, and killed with a bite to the head to shatter the skull. Herrersaurus stalks its prey slowly and silently, leaping upon its victim at the last minute.