Fossilized plesiosaur vomit reveals Jurassic feeding habits

Paleontologists have discovered fossilized vomit, known as regurgitalites, off the coast of Norway that provides new insights into the feeding habits of plesiosaurs. The study, published in Geological Magazine, analyzed more than 20 fossilized masses recovered from drill cores in the North Sea.

The specimens likely belong to the genus Cryptoclidus, a Jurassic marine reptile that could reach eight meters in length. Unlike many large marine predators, these creatures possessed teeth better suited for gripping rather than crushing. Consequently, they swallowed prey such as shellfish whole, later expelling indigestible remains in compact pellets similar to modern owl pellets.

A key finding of the research led by Dr. Dirk Knaust is the discrepancy between the prey and the location of the fossils. While the contents consist of marine organisms that require stable ocean salinity, the fossils were preserved in sediments from an ancient river delta. This suggests that plesiosaurs likely hunted in deeper offshore waters and then moved into shallower coastal river deltas before regurgitating their meals.