Utahraptor

## Physiology

### Attributes

Large size; serrated teeth; 12-inch sickle claw; large talons and claws; speed & agility; high intelligence; largest and strongest dromaeosaur.

## Biography

### Status

Extant (on Primeval Island)

***Utahraptor*** (name meaning "*Utah Thief*") is a genus of large dromaeosaurid theropod dinosaur that originated during the Early Cretaceous period in what is now North America. Roughly larger than a bear and undoubtedly the most terrifying creature of all time, *Utahraptor* is the largest dromaeosaur. Their size was great enough to enable these monstrous raptors the potential to attack even small Sauropods. Like the later raptor species, *Utahraptor* was armed with sickle-like claws on its hind legs and it had self-replenishing teeth in its jaws. Thus, these pack-hunting killers were well-armed.

Thought to have been extinct for 100 million years, there are still large packs of *Utahraptor* that remain alive on Primeval Island. In fact, they are the largest raptor on the island.

## Facts

### Era & Region

*Utahraptor* first appeared in western North America during the Early Cretaceous period and even lived through to the Middle Cretaceous, between 140 to 100 million years ago. While smaller than many of the predators of the time, due to its large size, *Utahraptor* was one of the apex predators of its environment. It lived alongside other animals such as *Deinonychus*, *Iguanodon*, and *Pteranodon*.

### Discovery & Range

Hence its name, the first specimens of *Utahraptor* were found in 1975 by Jim Jensen in the Dalton Wells Quarry in east-central Utah, near the town of Moab, but did not receive much attention at the time.

Around 15 years later, after finding a large foot-claw by Carl Limoni in October 1991, James Kirkland, Robert Gaston, and Donald Burge uncovered further remains of *Utahraptor* in the Gaston Quarry in Grand County, Utah, within the Yellow Cat and Poison Strip members of the Cedar Mountain Formation. Therefore, *Utahraptor* is known from a well-preserved skeleton found in 1991 in Utah, USA and fragmentary remains from South America.

In 2018, it was proposed that *Utahraptor* be the Utah state dinosaur, an act that was approved by the Senate. Initially *Utahraptor* would have replaced another dinosaur, *Allosaurus*, as the state's official fossil, but it was decided that Utahraptor would be another symbol of the state.

### Physical Attributes

A species of dromaeosaur notable by their enormous size, *Utahraptor* stood 6 – 8 feet (2 – 2.4 m) tall, measured 16.5 – 24 feet (5 – 7 m) in length, and weighed in at over 500 – 680 kg (1,100 – 1,500 lbs.), comparable in size to a large bear. This makes *Utahraptor* the largest and strongest dromaeosaur that ever existed. *Utahraptor* had large eyes coupled with excellent vision that allowed them to see in the dark and long grasping hands with large, sharp ripping claws. Its toe joints were specially enlarged so that its massive claw could be raised upward and backward to avoid damage while running. The unique wrist-joints of *Utahraptor* allowed the hands to pivot sideways, an action similar to the folding of a bird's wing.

But when used in an attack, its huge slashing claw flexed forward as the animal kicked out. Swinging in a wide arc, its huge, 9 – 15 inch (22 – 38 cm) slashing claw would produce terrible wounds enabling a Utahraptor to cripple and kill animals much larger than itself. With lethal claws, these killers were well-armed, and long fingers allowed them to latch onto swift-moving, larger prey.

Their body build is muscular, but relatively slim and lean, fitting their consistently active lifestyle. Although they were very fast, agile, and flexible theropod dinosaurs, able to reach speeds of up to 20 – 28 mph (32 – 45 km/h) and leap an amazing 15 feet (4.7 m) into the air, *Utahraptor*, however, had the short legs of a sprinter and did not pursue their prey for long. Despite their large size, *Utahraptor* could crouch down to the ground, which gave them the ability to use even the slightest cover if needed. Without being seen, they could peer over cover while remaining hidden.

### Behavior & Traits

Without a doubt the most terrifying creature that ever walked the earth, *Utahraptor* was an extremely aggressive, very cunning, and highly intelligent theropod dinosaur, being able to ambush, startle, and then attack their prey, despite being small in comparison to most. Like many predatory dinosaurs and all species of raptors, even *Utahraptor* was a social dinosaur that lived and hunted in packs; in numbers from a minimum of 3 to as many as 12 individuals in a single pack, from full-grown adults to assorted young.

Lead by Alpha, *Utahraptor* lived in jungles, open grasslands, and alpine environments, as the thick forests and rocks provide cover for them and nests for their young. *Utahraptor* nests were dug out amid the roots of giant jungle trees. All chicks were the responsibility of the entire pack, who brought back food for the young. While out hunting, a single guard or even two would remain behind, watching over the nest.

*Utahraptor* was a deadly and vicious predator, able to quickly and brutally kill their prey. Their hunting territories were large and well-marked, with a mixture of tree scrapings, urine, feces, and the like. Surprisingly, *Utahraptor* would sometimes conceal themselves for an ambush by burying themselves in rubble in the area.

When hunting, *Utahraptor* preferred to stalk and follow their prey unseen under the cover of vegetation and/or darkness, before emerging from their cover and swiftly closing in for the kill. They would ambush their prey, getting as close as possible before bursting out of cover and chasing down its prey. They were very efficient at using the terrain of their region to their advantage and would chase prey into canyons or over low cliffs.

They also had a hard time going without a kill for more than a week. Whenever they made a kill, they ate as much as 100 kilograms in each sitting. Whenever they ate, there was a strict pecking order in their feasts, and the large adults come first, whereas the younger and weaker Utahraptors would be nearby and have to wait their turn. Because of their large size, *Utahraptor* hunted anything from animals as small as the Hypsilophodonts to even small sauropods.

## Trivia

* The sound effects of *Utahraptor* are that of cougar and leopard sound effects, as well as the sounds of the Venatosaurus from Peter Jackson's King Kong game and the Dilophosaurus sounds from the PS3 video game Turok. They also produce an unknown screaming sound effect.