a polar bear lays on a rock
Like a polar bear, Nanuqsaurus was the top Arctic predator and had a great sense of smell for hunting.

Unsplash Photo / Andy Brunner

a computer image of a nanuqsaurus running
Nanuqsaurus means "polar bear lizard" from the Alaskan Inupiat word "Nanuq" in recognition of its role as top predator in the Arctic. It is a tyrannosaurid dinosaur ("tyrant lizard") that is very closely related to Tyrannosaurus rex but about half the size, prompting the nickname 'polar pygmy'.

Identification Level: Genus
Scientists recently realized that theropod bones found on Alaska's North Slope of Alaska belonged to a new genus: Nanuqsaurus. Geographic proximity, rock age, and foot shape suggest that this fearsome predator likely roamed Denali as well.

What is for dinner?
Being top predator in the region meant many other dinosaurs could have been on the menu. However, if prey species migrated seasonally, Nanuqsaurus may have had plenty to eat in the summer and been left searching for food in the winter.

a three-toed fossil of a dinosaur track

NPS Photo / Chad Hults

How do we know I lived in Denali?
Dozens of medium-sized three-toed theropod tracks have been found in Denali. The larger of these tracks were attributed to an unnamed small relative of Tyrannosaurus rex until 2014 when Nanuqsaurus became the most likely candidate.

Fun Fact
Nanuqsaurus, known from bones from northern Alaska, was likely the top predator in the ancient floodplain ecosystem that is now preserved within Denali.
a size comparison that shows a nanuqsaurus would be taller than an average man
How do I size up? - Although in the tyrannosaur world Nanuqsaurus is considered small, we would feel like a 1,000 pound, 25-foot long train car was racing towards us!

Last updated: August 16, 2016

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