Monday, February 28, 2011

Freaking huge lambeosaurs of the Judith River Formation

It's always an exciting time when we come to the end of a project. Mostly because it's one of those rare times where we're finished with something. This week we're finishing the right leg from an exceptionally big lambeosaur (crested duckbill dinosaur) that was discovered this past summer in the Judith River Formation by Dr. Kraig Derstler. We were very excited at the time about the find since big articulated dinosaur legs usually lead to big articulated more complete dinosaurs. Usually.

Digging revealed that it was highly likely that the entire skeleton was present at one time in the late Cretaceous, however everything but this right leg (animal was probably laying on its right side) was eroded away during the Campanian. Oh well, it stings a little less when you know you're 78 million years too late.

We had help from some great ranchers and their newfangled power ATV things getting the specimen out of the bottom of the uncharacteristically wet gully. Without them, the leg would still probably be there riding out the winter. Above are ranchers Matt Wickens and Kerry Simac, with "field chef" Peter checking his gear. Below Jacob is pointing to the specimen, while rancher and dino finder extrordanaire Larry Tuss rests. I'm just sorta holding up the "outfit" as they call vehicles in Montana.

A few months later this is the result. A reasonably complete prepared leg. Missing the fibula, astragulus and calcaneum due to erosion, and the ungual on digit IV. The monster is 11 feet long (3.36 meters). Biiiig.


  1. Crikey. that's quite a leg.What's the estimated length of the animal?

  2. Just some arm-waving stats, but based on other duckbills we've done in the past, a length of 38-40 feet isn't out of the question. We've recovered other isolated elements from monster duckbills in the past (such as a rib nearly 6 feet in length) bot nothing as complete as this so far.

  3. Although a theropod man at heart, I'm continually fascinated by hadrosaurs and their incredible success. They've been termed the Cows of the Cretaceous - not a terribly respectful term. And look at the size of this animal - magnificent.
    Hadrosaurs rock!

  4. Awesome find. I hope to search the Judith River and Two Medicine formations someday.

    On the subject of brig freaking hadrosaurs: There's a lambeosaurus arm bone from Baja California that indicates an animal 50 feet long and perhaps 20 tons in weight.