Richard T. McCrea
Tumbler Ridge became a site of palaeontological interest when two boys, Mark Turner and Daniel Helm, discovered a trackway of an armored dinosaur (ankylosaur) on the bank of Flatbed Creek a short distance away from their hometown (Helm, 2001, 2002; Kelsey, 2003; McCrea, 2003; Shilts, 2001). This discovery sparked a general enthusiasm in palaeontology in many of the residents of Tumbler Ridge who began to systematically explore the river valleys, canyons and creek beds in the area. Several new and significant finds were made, primarily of fossil vertebrate tracks and tracksites. The fossil track finds were confirmed and studied by University of Alberta Ph.D. candidate Rich McCrea, a student who specializes in the study of fossil footprints.
In the summer of 2002, the Tumbler Ridge Museum Foundation (T.R.M.F.) organized an informal prospecting expedition into a nearby canyon. The purpose behind the expedition was to confirm the recent discoveries of fossil dinosaur footprints and to perhaps find additional specimens. The expedition attracted many participants and was led by Rich McCrea and Dr. Charles Helm, the towns physician (McCrea, 2003). Several fossil footprints were discovered during the course of the day, but near the end of the trip the group came to an area where several large sandstone blocks had fallen from the sides of the canyon and were found resting on the floor of the canyon on both sides of the creek. In some of the blocks it was easy to see the remains of large tree stumps (Figure 1), as well as large iron-rich pebbles and numerous clamshells. One of the expedition participants, Wayne Sawchuk of Moberly Lake, British Columbia was the first person to notice the presence of fossil bone in one of these fallen blocks (Figure 2).
Once that initial find had been confirmed as an actual dinosaur bone, becoming only the second such discovery in British Columbia, more fossil bones were discovered on other blocks in the immediate area. The majority of the finds were contained on one block, designated as 'Block A' for future reference. In all, during that initial expedition, twenty dinosaur bones and bone fragments were found giving Tumbler Ridge 95% of British Columbias known dinosaur bones (McCrea and Buckley, 2004). The bones were encased in extremely hard rock, rendering normal picks, chisels, and hammers useless as excavation tools.
Following the success of the 2002 expedition and advice from Rich McCrea, the T.R.M.F. decided to organize a formal excavation of British Columbias first dinosaur bones the summer of 2003. The foundations ultimate goal was to have the recovered dinosaur bones prepared, studied, identified, and displayed in Tumbler Ridge. This was a bold decision, as at the time it was made the T.R.M.F. possessed no excavation equipment, preparation tools or a building where the bones could be safely and properly stored.
Facing an excavation budget alone of nearly $30,000, the T.R.M.F. began an aggressive and immensely successful funding campaign. One of the first supporters of the project was the Royal British Columbia Museum. Through its Living Landscapes outreach program the museum was beginning a focus in the Peace River Northern Rockies region from 2003 through 2005.
Building on the support of from Living Landscapes the T.R.M.F. was soon able to attract a wide range of supporters which enabled the purchase or lease the necessary equipment for the dinosaur excavation. Some of the equipment purchased included a variety of air tools (air scribes and air hammers) as well as two electric air compressors to run them. Since their was no power in the canyon, a 2,000 pound, 25,0000 watt diesel generator had to be flown in to run the air compressors and work lights (Figure 3).
Once the equipment had been set up (Figure 4) work began on the main bone-bearing rock (Block A). It appeared that the majority of bones were concentrated on one rock horizon within the block, approximately 75 cm below the top of the block. The first job was to remove this 75 cm thick cap of rock to expose the main bone layer. At first this job was accomplished using heavy sledgehammers and wedges (Figure 5), and air hammers. Even though it was suspected that the majority of bones were nearly a meter under the rock the excavation crew tried to remove the rock in 1-2 cm layers, just in case there bones in the upper layers. This was a well-founded precaution because bone was encountered throughout the block. Most of the bone was small and fragmentary, but here and there were pieces that were larger, and even some of the smaller bones were identifiable as fish scales, turtle jaw, crocodile scute and ankylosaur dermal armour.
The heavier equipment was abandoned once bone was encountered and the excavation crew switched to using air scribes, small, pen-sized instruments with a carbide tip that move back and forth at a very rapid rate (Figure 6). First the bone was stabilized with special glue, and then a trench was made around the bone with the air scribes until the bone was on a pedestal of rock (Figure 7). A plaster support jacket for the bone-bearing rock was created to make sure that the bones could be removed and transported out of the canyon safely (Figure 8).
The excavation ran a total of six weeks starting in the last week of June and ending in the first week of August. During the course of the excavation over 75 bones were uncovered and more than 60 were removed (McCrea and Buckley, 2004). Though final identification of the bones can only be made once they have been prepared, the remains are known to represent several vertebrate groups including dinosaurs. The bones of three different dinosaurs were identified including those of theropods, ornithopods and ankylosaurs. Bones of other vertebrates were also found including material from crocodiles, turtles and fish.
The bones were either flown or carried out of the canyon at the end of the excavation and taken to their home in the newly established Peace Region Palaeontology Research Centre (P.R.P.R.C.) where they will be prepared (Figure 9). In addition to preparing the material from the 2003 excavation, the T.R.M.F. and the palaeontologists of the P.R.P.R.C. are planning another excavation of the main block in the canyon to recover yet more dinosaur bones.
The dinosaur bones of Tumbler Ridge are significant, not only for being the first major find of dinosaurs in British Columbia's, but also because they are western Canada's oldest dinosaur bones, being nearly 20 million years older than those found in Alberta's great dinosaur bone deposits. The bones are also significant in that they come from a period of time (approximately 93 million years ago) when dinosaurs and other land animals were not well preserved on a global scale. It will be exciting to see how much we can learn about British Columbia's dinosaurs during the course of further excavation, preparation and study.
Helm, C. 2001. Tumbler Ridge: enjoying its history, trails and wilderness. Tumbler Ridge: MCA Publishing.
Helm, C. 2002. Making tracks in Tumbler Ridge. The Great Canadian Fossil Trail Newsletter , 3(3): 4.
Kelsey, E. 2003. Canadian Dinosaurs. Toronto: Maple Tree Press, 96p.
McCrea, R.T. 2003. Fossil tracks from Tumbler Ridge: a brief history of collaboration between amateurs and academics. Alberta Palaeontological Society Seventh Annual Symposium Abstracts Volume : 41-48.
McCrea, R.T., and L.G. Buckley 2004. Excavating British Columbia's first dinosaurs and other palaeontological projects in the Tumbler Ridge area. Alberta Palaeontological Society Eighth Annual Symposium Abstracts Volume: 24-33.
Shilts, E. 2001. Walk this way. Canadian Geographic, v121, no.6, p.30.