Enormous Jurassic Sea Predator, Pliosaur, Discovered In Norway

The 150 million year-old Jurassic fossil was discovered on the remote Norwegian archipelago of Svalbard, at 78 degrees north latitude, approximately 1300 km (800 miles) from the North Pole. It was found in the summer of 2006 by a team of Norwegian paleontologists and volunteers from the University of Oslo Natural History Museum, led by Dr. Jørn Hurum. The fossil was excavated in the summer of 2007 and has until now been prepared and conserved by a team at the Natural History Museum in Oslo .

A pliosaur is a type of plesiosaur, a group of extinct reptiles that lived in the world's oceans during the age of dinosaurs. Pliosaurs had a tear-drop shaped body and two sets of powerful paddles that it used to “fly” through the water. Their short neck supported a massive skull full of an impressive set of teeth. Pliosaurs were the top predators in the sea at the time, preying upon squid-like animals, fish, and even other marine reptiles. 

Pliosaurs were large reptiles that averaged 5-6 meters (16-20 feet) in length. One of the largest pliosaurs known is the Australian giant Kronosaurus , which measures in at 10-11 meters (33-36 feet) long. The new Norwegian find, named “The Monster” by team members, is estimated to be about 15 meters (50 feet) long, making it one of the longest and most massive plesiosaurs yet found.

“Not only is this specimen significant in that it is one of the largest and relatively complete plesiosaurs ever found, it also demonstrates that these gigantic animals inhabited the northern seas of our planet during the age of dinosaurs” said Dr. Patrick Druckenmiller, a plesiosaur specialist at the University of Alaska Museum, and a member of the expedition that found and excavated the fossil.

The team made the discovery in the summer of 2006, when parts of the skeleton, including skull fragments, were found weathering out of the side of a mountain.

“We knew immediately that this was something special. The large pieces of bone and the structure on the fragments told us immediately that this was something big” said Dr. Jørn Hurum.

A larger crew returned in August of 2007 to excavate the fossil. After removing about hundred tons of rock by hand the team was rewarded by uncovering a significant portion of the skeleton.

“Although we didn't get the entire skeleton, we found many of the most important parts, including portions of the skull, teeth, much of the neck and back, the shoulder girdle, and a nearly complete forelimb (paddle)” said Druckenmiller, “Amazingly, the paddle alone is nearly 10 feet long.”

During its excavation in the summer of 2007, the team of paleontologists and volunteers had to endure challenging arctic weather – high winds, rain and fog, and temperatures hovering around freezing. The team completed their fieldwork in a mid-August blizzard. Throughout the three-week field season the team also had to be constantly on the alert for polar bears.

Although the crew focused on removing the “The Monster”, parts of two other marine reptiles were also collected – a long-necked plesiosaur and an ichthyosaur, a type of extinct sea reptile form the age of dinosaurs that superficially resembled modern dolphins. Based on the wealth of finds, scientists now recognize Svalbard as home to one of the richest accumulations of marine reptiles in the world.

“The scientific value of such a large locality with unknown species of marine reptiles is just staggering” Jørn Hurum comments.

The bones collected last summer are currently undergoing the slow process of cleaning at the Natural History Museum in Oslo .

“From the bones we have finished stabilizing so far this absolutely looks like a new species” Jørn Hurum tells enthusiastically.

Last summer's field work ended on a high note; after the team finished excavating the new find, parts of a skull and skeleton from another gigantic pliosaur, possibly of the same new species, were found weathering out at a different site. The team is currently planning to return this upcoming summer in order to excavate the skull during Svalbard 's short summer field season.

“All together we have GPS-coordinates on 40 skeletons of different marine reptiles in the area. We will have work for many years to come” Jørn Hurum comments with a smile.

The scientific description of the monster and other new marine reptiles from the locality will be parts of a Ph.D. study by one of the members of the crew, Espen M. Knutsen.