Dinosaurs
in Central Montana
If Central Montana seems interesting today, wait until you check out our prehistoric past.
Today, Central Montana is one of the richest areas in the world for dinosaur fossils. Here you will find "hands on" archaeological, paleontological and geological experiences. And summer is an excellent time to dig dinosaurs along the Rocky Mountain Front or visit ancient archaeological sites.
The Montana Dinosaur Trail in Central Montana
More than 65 million years ago, the Montana landscape was very different than it is today. A large inland sea covered much of the area that is now Montana. It created a semi-tropical flood plain not unlike the Everglades of Florida today.
During the last days of the dinosaurs, large herds of these massive beasts lived, migrated and nested in the upland areas surrounding the shallow sea. Duckbill dinosaurs and horned dinosaurs known as Triceratops are two of the plant eating varieties that inhabited the area.
The Triceratops was a herd animal; it is believed that large groups roamed North America. Their large beaks and long rows of teeth were well designed for chewing tough, low growing plants. More than likely, the main predator of these animals was the Tyrannosaurus rex which means "tyrant lizard". A number of skeletons show bite and chew marks that match the teeth of T. rex.
The Central Montana's portion of the Montana Dinosaur Trail includes the following sites at Bynum, Chinook, Choteau, Havre, Harlowton and Rudyard.
The Montana Dinosaur Center, Bynum
Montana dinosaurs at the The Montana Dinosaur Center include the world's longest dinosaur, a full-size skeletal model of Seismosaurus halli (earth-shaker lizard); a Guinness Book of World Records listing at 137 feet long, nearly 23 feet tall at the hips. The Center also features the first baby dinosaur bones found in North America among its displays and is famous for its public hands-on dinosaur research and education programs. Advance registration required for most programs; some offer college credit. More
Blaine County Museum, Chinook
The Blaine County Museum's Paleontology Department displays a dozen Judith River Formation exhibits including Hadrosaur, Gorgosaurus and Ankylosaurus fossils from the area. Remains of gigantic marine reptiles Mosasaur and Pleisosaur are featured, along with invertebrates from the area's ancient ocean (75-500 million years past). In the Look, Touch and Wonder room, guests can handle fossils of sea creatures, plants and dinosaurs that roamed this area millions of years ago. More
H. Earl Clack Museum, Havre
Many dinosaur discoveries of world-wide significance have been found in Montana and along the Montana/Canadian border. One such find, 75 million year old dinosaur eggs with embryos found in the Judith River Formation, is on display in the H. Earl Clack Museum. Research suggests these eggs were laid by a Lambeosaur, a large duck-billed, plant-eating dinosaur that grew bigger than most of the meat-eaters of its time. More
Rudyard Depot Museum, Rudyard
The Rudyard area has provided dinosaur specimens for the Museum of the Rockies (MOR) and other premier institutions for years. Now an MOR affiliate, the Depot Museum’s signature display is the "Oldest Sorehead," a fully articulated Gryposaurus found near here. The facility’s lifelike duckbill dinosaur and egg nest display places you right next to these ancient creatures. Other permanent and changing dinosaur exhibits. Open Memorial Day to Labor Day. More
Upper Musselshell Museum, Harlowton
The Upper Musselshell Museum in Harlowton is also part of the Dinosaur Trail in Central Montana. The museum's centerpiece is a full-size replica of a skeleton found in the Judith River Formation near Shawmut: an Avaceratops, the first dinosaur found of its kind. The Avaceratops had a short, deep snout with a thick and powerful lower jaw. The museum also has a Hadrosaur tibia and fibula, a cast of a Gypsonictops jaw, a large ammonite (coiled chamber shell of an extinct mollusk), and much more. More
Old Trail Museum, Choteau
The last stop on the Dinosaur Trail in Central Montana is located near the Two Medicine Formation along the Rocky Mountain Front. The Old Trail Museum in Choteau features a "Dinosaurs of the Two Medicine" paleontology gallery. The area west of Choteau is where egg shell fragments and baby dinosaurs were found thirty years ago, forever changing how the world thinks about dinosaurs. More
Egg Mountain in Central Montana
In late July of 1978 Jack Horner visited the Rock Shop and Museum in Bynum, MT. Local resident Marion Brandvold had discovered baby dinosaur bones that she showed Jack. Laurie Trexler had also found an adult duckbilled dinosaur skull nearby. The baby bones were the first to be found in North America, and the first in a nest anywhere in the world. Both the babies and the skull were discovered while Dave and Laurie Trexler and Marion Brandvold were working on an adult dinosaur they planned to display in their museum. At the time, this display would have been only the second dinosaur on display in Montana.
Bob Makela and Jack Horner collected the skull and site materials from the baby locality. They also borrowed the baby bones collected by Marion. These were studied that winter and a preliminary report naming “Maiasaura peeblesorum” was published in Nature in 1979, before any eggs were discovered. A volunteer of Jack’s, Fran Tannenbaum, found the first eggs at Egg Mountain, approximately 3/4 of a mile from the original Maiasaura locality, in July of 1979.
Both Egg Mountain and the Maiasaura locality are rich in egg, baby, and adult fossils. The animals themselves roamed a broad flat coastal plain along the edge of the Cretaceous Interior Seaway approximately 77 million years ago. The Egg Mountain locality has produced remains of adult and embryonic Troodon (a small meat-eater) and adult Orodromeus (a small plant-eater), as well as remains of cretaceous mammals, lizards, and pterosaurs. The Maiasaura locality has yielded literally thousands of individual fossils, all believed to be from the single species of Maiasaura. The original Maiasaura nest contained remains of baby dinosaurs that had been hatched for some time before their demise. Because these individuals had remained in the nest after hatching, some individual (most likely the mother!) had to have been caring for the babies. This was the first indisputable evidence that dinosaurs were capable of any sort of complex behavior.
The Maiasaura’s round nests were six or seven feet wide and could hold up to 25 eggs. The hatched babies were about one foot long. Adult Maiasaurs weighed almost 6,000 pounds and were almost 30 feet long. The nests of Troodon at Egg Mountain itself are about half the diameter of the Maiasaura nests, but they contained roughly the same numbers of eggs.
Egg Mountain is located near Choteau, Montana, and dinosaur research continues in the area to this day. Both of Montana’s dinosaur research facilities are actively working on projects in the local Two Medicine Formation. While the Egg Mountain area is closed to the public, access to area fossils is available through public programs at the Two Medicine Dinosaur Center in Bynum, and undergraduate and graduate studies are available through Montana State University/Museum of the Rockies.