THE COAL OIL CANYON PLESIOSAUR

or... HOW WE MET PETE BUSSEN*

Copyright 2000-2009 by Mike Everhart

Last updated 09/19/2009

 

 

LEFT: Artwork copyright Doug Henderson; used with permission of Doug Henderson

Note that Pete Bussen was recently honored with the naming of a new fish (Apateodus busseni,  which he discovered, collected and donated): Fielitz, C. and Shimada, K. 2009.  A new species of Apateodus (Teleostei: Aulopiformes) from the Upper Cretaceous Niobrara Chalk of western Kansas , U.S.A. Journal of Vertebrate Paleontology 28(3):650-658.

Early one morning in August of 1989, we were sitting in the local cafe in Sharon Springs, Kansas, having breakfast, drinking coffee and killing time until Dr. David Parris and his crew from the New Jersey State Museum arrived. They had been part of the staff and students at the South Dakota School of Mines Field School and were coming back through Kansas to look at an exposure of Pierre Shale called 'Hell's Half Acre'. After working in the Pierre Shale in South Dakota, they wanted to compare it with the same formation in Kansas. After that, we were supposed to take them to our favorite hunting grounds in the Smoky Hill Chalk.

Sitting next to us in the small cafe were three ranchers. One man was talking about something he'd found. The conversation was fairly animated, and after a while I started picking up on some of the words, like 'bones' and 'big fish', and 'fossils' and 'washing out in a gully where the cows were walking on them'. The other two men were listening politely to the story but I could tell that they weren't terribly interested.

The temptation was too much and I finally asked the man if he was talking about a large, extinct fossil fish called Xiphactinus. His eyes lit up when he said that he was, and we started a conversation about fossils that went non-stop for the next half-hour. Finally, he asked what we were doing in Sharon Springs and we told him that we were waiting on another group so we could go on a field trip to the Pierre Shale. When I told him about 'Hell's Half Acre', he just shook his head and said there wasn't much shale there. Then we exchanged names and addresses. His name was Jerome Bussen, but everyone called him 'Pete'. He was a retired rancher and had lived in this part of the State all of his life. We told him that we'd get back in touch with him the next time that we were out in Western Kansas.

Then we told him that our friends were due to arrive at the courthouse in a few minutes and we'd better be going. We said our good-bye's and drove the three blocks it took to get to downtown Sharon Springs. A few minutes later, the two vehicles carrying the New Jersey crew pulled up and, after introductions all around, we started planning the day's trip.

About that time, Pete drives up in his dust covered Toyota sedan and comes over to meet the group. When we asked him about the best way to get to 'Hell's Half Acre', he said, "You don't really want to go there. Come on, I'll show you some shale."

Ten dusty, bumpy miles and thirty minutes later, we were driving across the native, unfenced prairie of the Surratt Ranch when the grasslands seemed to split apart and open into a series of deep (for Kansas), gray shale canyons. We parked on the south rim and Pete told us that this was called 'Coal Oil Canyon' because of the oily appearance of the water that came from the springs. He said he'd worked around there since the 50's when he was excavating paleo-Indian sites as part of an archeology project. He pointed out various landmarks and told us to go anywhere we wanted because there were fossils just about everywhere...and "Oh, by the way, watch out for the rattlesnakes when you walk down through the caprock."

The next couple of hours were frustrating for me because I simply could not distinguish fossil bone from the shards of shale and glittering selenite that littered the ground. Even the folks who had just spent two weeks digging in the Pierre Shale in South Dakota didn't find much either. What bone we did find was heavily encrusted and invested with selenite, making most of the material unrecognizable, and very ugly. No one else had much luck either, with the exception of one lucky soul who found an isolated mosasaur vertebra. Not just any vertebra, it was five inches across and looked as large as a one pound coffee can. Sure that we were about to find a monster of a mosasaur, we dug quite a hole trying to find more bone, but that was all there was.

About noon, less than impressed with the shale, we said our good-byes and went back to the chalk where we 'knew' we could find something a bit more interesting. We promised we'd keep in touch with Pete. The next time we saw him, it was two years later.

THE COAL OIL CANYON PLESIOSAUR

Pete lives right in the middle of some of the most productive fossil sites in the world. When he became interested in paleontology, he was able to spend a couple of hours in the field almost every day, weather permitting, year-around. Since he had grown up in the area, he knew just about everyone and had permission to hunt just about everywhere that chalk or shale was exposed.

It was on one of these daily excursions that Pete found his first (he now has several) plesiosaur. He was walking along the rim of the canyon, just below the short-grass prairie, and came across the scattered paddle bones of a large plesiosaur. He picked up the bones that had eroded out of the shale and noted where they were eroding out. Then he dug around enough to satisfy himself that most of a large, articulated paddle was still in the shale. Remembering that David Parris at the New Jersey State Museum was interested in plesiosaurs, he gave him a call and asked him if he was interested.

Not being a party to the conversation, I can only imagine what flashed through David's mind when he got the call and the offer to have a plesiosaur for the digging. Having talked to Pete several times since then, I now know what Pete was thinking. He realized that if the plesiosaur was complete, it could be as much as forty feet long. The site was ideal for digging, with only 3 feet of soil and shale over the remains, but that was quite a bit overburden over something as big as a plesiosaur. Pete decided from the start that he would rather watch someone dig up his plesiosaur than dig it himself....good choice!

David accepted Pete's offer, of course, and made arrangements to bring a field crew back to the site in August. As things go, however, most of the field crew couldn't make the trip and it was David Parris, Barbara Grandstaff, and myself that did most of the initial opening of the dig site. We arrived early on the morning of August 25, and walked around the site, trying to get an idea of how the remains were laid out. The emerging paddle elements were the only bones visible so we were reasonably assured that the rest of the animal was still safely contained in the shale. We spent most of the rest of the morning removing the overly in sod and soil in order to create a reasonably sized working area.

Me and the famous "Flying Shovel" (That's another paleo tall-story) engaged in one of the joys of paleontology....... clearing away the soil and shale (overburden) that covered the fossil remains. In this case, the plesiosaur was laying parallel to the edge of the gully, with just the tip of one paddle eroding out of the shale.   Neat hat, huh?

  Barbara and Dave started working on the exposed paddle while I "chose" an area at the extreme north edge of the dig. The gods of paleontology were definitely smiling on us that day. Just as Barbara and Dave began finding ribs and small round stones (gastroliths) in an area next to what appeared to be a front paddle, I dug down through 3 or 4 inches of shale and found another paddle.

This photo shows one of the front paddles after some initial excavation. The larger bones at the top of the photo are part of the shoulder (pectoral) girdle.
There were more than 100 gastroliths (stomach stones) in the abdominal cavity of the plesiosaur. Some of the larger ones weighed as much as a pound. The source of these particular gastroliths was definitely not anywhere in Kansas. This area also contained fish scales and fish vertebrae.

As they found more gastroliths in what was now definitely the stomach region of the animal, I continued to excavate around what appeared to be a completely articulated rear paddle. My excavation got larger though the afternoon until I had the entire paddle (4' long) and half the pelvis exposed. The shape of the pelvic bones was definitive enough that Dave decided that we were working on an adult Alzadasaurus....a long-necked plesiosaur related to Elasmosaurus. (Note that Alzadasaurus is now a junior synonym for Styxosaurus .... See Carpenter, 1999)

The job isn't finished (even in the field) until the paperwork is done. Barbara and Dave pause at the end of day one to make field notes. The red discoloration in the soil was limited to the abdominal region where the gastroliths were found. We speculated that when the plesiosaur died and sank to the bottom, most of its blood pooled in the abdomen, and the red stain is from the hemoglobin (iron) in the plesiosaur's blood .......sounds good anyway.
Barbara is still working the field notes, and making sure everything is lined up right. My contribution for the day was the discovery and uncovering of one of the rear paddles (foreground, lower left).
On Day 2, we were all somewhat surprised to find that I had spent Day one walking and working on top of the plesiosaur's caudal vertebrae. They ran parallel to the paddle, but were about 6 inches below the level of the excavation. We discovered that the shale was tilted and had to re-think our ideas on how the fossil was laid out.
Barbara and David applying a plaster jacket to the caudal vertebrae. The uncovered paddle is shown from a different angle. At this point, we believed the other rear paddle had already eroded out and been lost. It would be found the following year underneath this work area.
It was late in the day when they finished the jacket on the caudal vertebrae, and Barbara had just made a joke about "getting plastered". Typical paleo-humor when you've spent hours roasting in the August sun in Kansas.
This is a view of the top of the left rear paddle after I finished uncovering it on the second day of the dig.  It was really nice with every bone still in place, from the tip of the paddle to the socket of the hip.
paddle1a.jpg (18232 bytes) The same paddle (underside) after the jacket had been opened in the New Jersey State Museum and the paddle was being prepared .
While on the Coal Oil Canyon plesiosaur dig in 1991-92, I took notes in a small pocket notebook and then transferred the notes to my field book each evening.   The pages from the pocket notebook are: njnotes1, njnotes2, njnotes3, njnotes4, njnotes5 and njnotes6.  (1991 = 1-4; 1992 = 5 and 6).   The pages from the field book are: page1, page2, page3, and page4 (all from 1991). 
drawing3.jpg (3782 bytes) Click on the drawing at left for a sketch of the dig site. At the end of Day 3, Barbara and David packed all of the jacketed material into their truck and started for home. Most of the plesiosaur was still in the ground, but it would have to wait through another cold Kansas winter before finding a warm home in the New Jersey State Museum. The 1992 dig is next:

Click here for an article about elasmosaurs in Prehistoric Times magazine (#53, April 2002).

Click here to see the paper published by Cicimurri and Everhart in 2001 about this specimen

We complete the Dig: 1992

Gastroliths from the New Jersey Plesiosaur

"We Dug Plesiosaurs" - with the Cincinnati Museum in 1998

The 1999 Cincinnati Museum Plesiosaur Dig

The Styxosaurus snowii elasmosaur at the South Dakota School of Mines and Technology

The Denver Museum elasmosaur (Thalassomedon haningtoni)

The longest neck in the ocean" (University of Nebraska State Museum elasmosaurs)

About Plesiosaurs

About Pliosaurs

Plesiosaur References: A listing of publications related to plesiosaurs

A list of references in my library about mosasaurs and plesiosaurs

Also, you can visit Ray Ancog's Plesiosaur FAQ Page (Frequently Asked Questions)

Plesiosauria Translation and Pronunciation Guide

Barry Kazmer's Plesiosaur Paleontology Page

Richard Forrest's listing of plesiosaur specimens and literature