Yes, some dinosaurs did apparently live and travel in herds, probably because there was “safety in numbers.” Scientists have deduced this behavior based on dinosaur trackways and huge collections of dinosaur bones that indicate massive kills (places in which large amounts of dinosaurs bones are found in one place).

In particular, many herbivores apparently traveled in herds, based on the multiple tracks left along the dinosaur trackways. The tracks also show that many herbivores held the young in the center of the herd (similar to elephant and bison herds), most likely to protect them.

Some dinosaur fossils have been found in massive collections, indicating many dozens of animals were killed in one spot. Some scientists believe such collections of animal bones show the creatures exhibited a herding behavior. In many cases, while in the herd, these animals were swiftly killed off, perhaps from a major flood, volcanic action, or a huge sandstorm. For example, the bone beds of about 100 Styracosaurus dinosaurs, a herbivore, have been discovered, as have dinosaur bones that represent dozens of Protoceratops and Triceratops in herds.

One particular herbivore called a Maiasaura (a hadrosaur) is also thought to have lived in herds and probably returned to the same nesting grounds every year. Fossil bones of these animals were found in a huge group of about 10,000 animals in Montana. The animals all died suddenly, apparently when a volcano erupted, smothering the animals with volcanic gases and covering the creatures with a thick layer of ash.