During the summer of 2001 students from the University Center in Svalbard discovered a series of bones from a swan reptile in Janusfjellet not far from Deltaneset. Three years later scientists from the Museum of Natural History, University of Oslo, carried out an excavation at this location. Within an area of 200 meters the scientists recovered bones from two different marine reptiles: fish lizards and swan reptiles. Both species lived during the Jurassic. At this point far back in time dark and organic slate was formed. The slate might be the source for some of the oil deposits in the Barents Sea.
The plesiosaurs are also called swan reptiles. They ranged in size from a few meters up to 13meters in length. They lived during the Mesozoic Era, from the Triassic period until they died out, along with the dinosaurs, some 65 million years ago. They mostly inhabited the sea, but were also found in freshwater. The plesiosaurs fed on fish and squid. They are divided into two groups: one with long necks and one with short necks.
Icthyosaurs (fish lizards) are reptiles with dolphin-like bodies that lived in the sea during the Triassic, Jurassic and Cretaceous periods.The forelimbs were evolved into fins and they had a fish-like tail. They were experts at catching squid and fish and had the largest eyes that any vertebrate has developed. They are rare in the Cretaceous period and disappears before the extinction of the dinosaurs.