Hadrosaurus is one of the dinosaurs that are cloned by InGen in the first novel. The Hadrosaur herd in the park consisted of 11 individuals. They shared a paddock with Maiasaura, due to them being close relatives of Hadrosaurus, Apatosaurus, and Microceratops. No reproduction is observed among the Hadrosaurs. Both the Tyrannosaurus rex and the Velociraptors were able to reach their territory and take some down. One of the most dramatic scenes involved the Tyrannosaurus rex causing the Hadrosaurus herd to stampede, in which case it successfully hunted and killed one individual, while the rest of the herd nearly trampled Dr. Alan Grant and the Murphy children. In the film, this scene was ultimately replaced with a Gallimimus stampede. At the end of the novel, it is shown that only 5 Hadrosaurs are left. One is later killed by a pack of raptors, leaving only 4 individuals left. The rest are later killed by the Costa Rica Napalm Bombing.
