Hadrosaurus foulkii (S/F)

Hadrosaurus is a hadrosaur, or duck-billed dinosaur, native to the East Coast of North America in the Late Cretaceous period around 79.5 million years ago. It was the first North American dinosaur fossil identified by more than isolated teeth. Originally found in 1839 in Haddonfield, New Jersey, Hadrosaurus is primarily known from limited material. It was named by paleontologist Joeseph Leidy in 1858. The species name foukii honors William Parker Foulke, a philanthropist who was pivotal in the discovery and naming of the animal. Hadrosaurus itself means “bulky reptile” or “large reptile.” The material found for Hadrosaurus was a set of limbs, pelvis, parts of the feet, 28 vertebrae, eight teeth. and two very small and fragmentary pieces of the jaw. The discovery of Hadrosaurus demonstrated to scientists and the public at the time that there were many new fossil species to be discovered in North America. It also gave a gentle push for scientists into a more accurate direction regarding restorations of dinosaurs. In fact, Hadrosaurus was restored at the time in a bipedal stance, unlike Iguanodon and Megalosaurus, which had been restored as quadrupedal animals a couple decades before.

Hadrosaurus was probably cloned by InGen at some point in the late 1980s or early 1990s, but none existed in 1993 when the last known asset catalogue was created. It was not included in a list of current assets, suggesting that InGen might have given up on this species.

Early prop from The Lost World: Jurassic Park featuring Hadrosaurus. An altered version was used in the film, but cannot actually be seen on screen.

The appearance of Hadrosaurus is mostly unknown, as only one incomplete fossil has ever been found and the animal has not appeared in any of the films. However, a prop featuring the animal has surfaced, depicting it as a typical small hadrosaur with no head ornamentation and a comparatively short tail. Existing photographs of this prop are impossible to read, but the animal appears to be 15 to 20 feet in length and around seven or eight feet tall when standing on its hind legs. A short, muscular ridge can be seen on its back, and the small head terminates in a thick keratinous beak structure with large nostrils. The beak appears to overlap the front of the animal’s lower jaw, concealing the lower jaw when the mouth is closed.

Coloration remains unknown, as the illustration is only a sketch and no readable version of its description has yet to be shared. There appears to be some striping on the dorsal side, but this may be creases in the skin rather than pigmentation.

A Hadrosaurus icon on the holoscape attraction at the Samsung Innovation Center in 2015 depicts a similarly-proportioned animal.


Hatchling and juvenile stages have not been depicted.

Sexual Dimorphism

No sexual dimorphism is known in this animal due to lack of observed specimens.

Preferred Habitat

The only known fossil of Hadrosaurus was recovered from marine sediments from the Woodbury Formation, suggesting that the animal had been washed out to sea by means of a river. This suggests that it lived near sources of fresh water. It appears to have died out sometime before 1993, so it might not adapt well to the modern world.

Muertes Archipelago

No Hadrosaurus have ever been reported on Isla Sorna of the Muertes Archipelago, but it appears they were cloned at some point. However, they were not included in a 1993 list of current active and inactive assets, despite the asset catalogue including it in a different section. This more or less implies that, while InGen did clone Hadrosaurus, it no longer existed by 1993.


Isla Nublar

No Hadrosaurus have ever been reported on Isla Nublar. Its DNA was on site as of 2015. The Jurassic World Cookbook indicates that its intended habitat was the Jungle River, which was already inhabited by other hadrosaur species.

Mantah Corp Island

Since none are known to have been cloned, it is unlikely Mantah Corp ever bred this dinosaur at their island facility.

BioSyn Genetics Sanctuary

After the release of de-extinct animals into the wider world, various national governments authorized BioSyn Genetics to capture and contain many of the animals that were causing problems. Captured specimens were housed at facilities such as the BioSyn Genetics Sanctuary. Hadrosaurus, which does not appear to have ever been successfully cloned in the modern day, is unlikely to be among these species.

Black market

Since InGen did possess DNA from this species, and it may have been viable, it is likely that specimens exist somewhere in the world. After the events of 2018 made de-extinction technology open-source and sent many samples of ancient DNA onto the black market, it is possible that a person with the means to do so could finally, successfully clone Hadrosaurus, but there is no evidence this has happened. Someone hoping to create this dinosaur might have luck finding specimen samples at the Amber Clave, the most notorious night market for de-extinction technology and specimens. It operates at a range of clandestine locations in Valletta, Malta.

Wild populations

Although fossils are rare, they confirm that this dinosaur lived in the Appalachian region of North America during the late Cretaceous period. It lived around eighty million years ago, during a time at which Appalachia was a subcontinent of North America divided from the western Laramidia by the Western Interior Seaway. Since very little information about the time range and geographic distribution of Hadrosaurus exists, it is unknown how common it was, and not much is certain about why it went extinct. DNA belonging to this species survived and was recovered by scientists in the late twentieth century; sadly it had little luck in the age of de-extinction as no living specimens seem to persist today.

There is currently no evidence that Hadrosaurus has been cloned again at any location.

Behavior and Ecology
Activity Patterns

The activity patterns of Hadrosaurus are unknown.

Diet and Feeding Behavior

All hadrosaurs are herbivores, and most are known to feed on conifers, horsetails, broad-leafed plants, seeds, and fruits. It is believed that they were grazers which could chew their food.

Social Behavior

While the social behaviors of Hadrosaurus are unknown due to the animal not being observed, its relatives Edmontosaurus, Corythosaurus, and Parasaurolophus have been observed to be highly gregarious and enjoying the company of other herbivorous dinosaurs as well as their own species.


As with all dinosaurs, Hadrosaurus would lay eggs to reproduce. It presumably had a cloaca, similarly to Parasaurolophus. Most hadrosaurs lay average-sized round eggs which incubate for three to six months, but specific details for Hadrosaurus are unknown due to a lack of specimens.


This animal’s vocalizations, while they would have been displayed on the holoscape, are currently unknown to us.

Ecological Interactions

Hadrosaurus was a herbivore which preyed on plants in its habitat, and was prey itself for medium-sized and larger carnivores. Apart from this, its ecological relationships are uncertain.

Since Masrani Global Corporation was in possession of Hadrosaurus DNA, it is likely that Hadrosaurus would have been host to hematophagous (blood-drinking) parasites such as mosquitoes.

Cultural Significance

As one of the earliest discovered hadrosaurs, this dinosaur has long been represented in paleoart despite the limited nature of its remains. It is the state fossil and state dinosaur of New Jersey and is generally considered to be a source of pride for this state’s scientific history. Hadrosaurus is considered emblematic of the hadrosaurs in general, with the group being named for this creature. It also honors the philanthropist William Parker Foulke with its species name. Its genus name is a play on words; while it translates to “big reptile” or “sturdy reptile,” Foulke and Leidy originally meant for it to sound like Haddonfield, where it was found.

In Captivity

No Hadrosaurus have been observed in captivity; they appear to have died out before 1993. Its closest de-extinct relatives are other hadrosaurs, including the lambeosaurines Parasaurolophus and Corythosaurus and the saurolophine Edmontosaurus. The needs of captive Hadrosaurus can probably be estimated based on these. Since it did not flourish when InGen originally created it, special accommodations might be necessary to keep it alive. Its intended Jurassic World exhibit was the Cretaceous Cruise.


Originally discovered in a marl pit near Haddonfield, New Jersey and put on display in a local man’s home, Hadrosaurus soon gained scientific fame as the first dinosaur known from more than teeth in North America. It was a major factor in a revolution in the way paleontologists viewed dinosaurs, demonstrating that these huge animals could be bipedal rather than being restricted to a four-legged gait. Hadrosaurus was the first dinosaur ever to have its skeleton put on display, constructed in 1868 for the Philadelphia Academy of Natural Sciences.

In the Genetic Age, this animal has gained some attention as well. Its genome was sequenced by International Genetic Technologies, expanding the company’s genetic library to include one of the more basal hadrosaurids and thereby uncovering new information about hadrosaur evolution.


Hadrosaurus is the official state fossil and state dinosaur of New Jersey, designated in 1991.


Aside from the paleontological knowledge it presents, the main resource obtained from Hadrosaurus in the modern day has been science communication and entertainment. It was one of many genera featured in the holoscape exhibit at Jurassic World‘s Samsung Innovation Center, where visitors could swipe an icon to generate a life-sized hologram of this dinosaur that would move and vocalize like the real animal. At the moment, it is not known whether there were any plans to clone the species.


Since this dinosaur is currently extinct, it presents very little threat. However, should it be brought back to life, the same safety procedures and precautions used for other hadrosaurs would most likely apply.

Behind the Scenes

During the production of The Lost World: Jurassic Park, a template was created for Hadrosaurus to appear in Roland Tembo‘s manifest; however, the design for the species packet was changed and the animal itself was not included in the final film. In the original script for the film, it would have been one of several species which Dr. Robert Burke assigned particular hunters to track down and capture, along with Maiasaura and Corythosaurus (misidentified as “Maiasaurus” and “Carinthosaurus”). The script did not identify it at any other point, but presumably it would have appeared.

In 2021, the screen-accurate prop for Roland Tembo’s manifest finally surfaced among other The Lost World: Jurassic Park props. It confirms that Hadrosaurus was present in the manifest.

Disambiguation Links

Hadrosaurus foulkii (CN)