This entry is an update of our plans as of Friday, May 29, 2009. The T. rex fossil site that we had hoped to excavate will not happen this summer. The Eighth Circuit Court of Appeals has not published a decision on the case and therefore, we are not allowed to proceed with the project. I am a little disappointed since this was to be a "once in a lifetime" opportunity. However, it turns out that at the end of the field season last year, a fabulous fossil fish site was discovered in an area of the Hell Creek formation just north of where we have worked in past years.
About 45 miles north of Buffalo South Dakota, in North Dakota, is a most remarkable bed of fish that appear to have died simultaneously as a result of some catastrophe. The fish are beautifully preserved in such a way that you can see the fins, scales and even faces. Yes, fish faces. Extraordinary! Anyway, the site is extremely important and must be excavated this summer since these fossils are much more fragile (than T. rex bones) and at risk of deterioration from exposure. Our team of 40 volunteers will have a unique opportunity to work on a project that has the potential of adding new fish species to the list of those known to have lived during the Cretaceous Period, 65 million years ago.
A fossil fish expert from the Field Museum in Chicago has identified one of the fish as a sub species of sturgeon, and the other one is so far unidentified. So I guess that means it could be a new species. Now that is exciting! He has been looking at photographs taken of the fish that were removed and cleaned from last year's excavation. I do not believe he has seen the fossils in person.
Steve Nicklas, our paleontologist professor/coordinator, for this project is extremely enthusiastic about the prospects of finding additional fossils at the site. One could speculate that whatever caused the death of so many fish, could have also brought about the deaths of other animals in the area. Perhaps the animals were foraging near a lake when disaster struck, and many species were trapped. We will be on the lookout for fossil birds, reptiles and dinosaurs. It would be truly fabulous to find evidence of plants as well so that we would begin to get a picture of what that particular site looked liked 65 million years ago.
Though the "King of the dinosaurs" may have to wait for another year, I am really excited about this summer's dig. I have most of my supplies since this is my third year. The only item I need to purchase specifically for this work is a gardening knee cushion that can be used for sitting or cushioning your knees. Steve will be providing each of us with the specific tools required for the project. There is only a thin layer of overburden, so thankfully, I don't think there will be need for shovels and wheelbarrows to remove pounds of heavy soil. Overburden is the layers of soil that covers the matrix the fossils are in. At the T. rex site, the overburden is about 8-10 feet deep. That is a heck of a lot of earth to move. At the fish site, the overburden is minimal, in fact I think it is measured in inches. The work will focus on stabilizing and wrapping/crating each fossil.
I am now trying to learn more about fossil fish in the last three weeks before departure. I have found fossil fish vertebrae in my previous trips, but that is quite different from looking at a whole fish. I will focus on the types of fish that were swimming around in the Cretaceous in the Hell Creek Formation. So far I know there were gar, sturgeon, bowfin, drumfish, coelacanth, sharks and rays. I want to have a pretty good idea of what they looked like so as I am working I can recognize head from tail, and hopefully what's in between. The challenge is always trying to discern what you are looking at when it is covered with dust from 65 million years ago. Learning from illustrations in books versus field observation takes practice. I suspect I will get plenty of the latter when June 22nd gets here, and for now I will focus on what books and the internet offer.
More locally, I often take beach walks since we live on the coast of Southern California. On occasion the surf washes up a bone from a bird, mammal, or fish. A few weeks ago as I was picking up trash on my morning beach walk I spotted something white in the surf. I picked it up and it reminded me of a fossil I found in South Dakota two years ago. I was pretty sure it was a fish verterbra, but I did not know what kind of fish. It was a big fish, of that I am convinced. I was in Monterey last week and showed it to Monterey Bay Aquarium docents, but though they assured me it was from a fish, they could not identify the species. I have a friend who is a marine ichthyologist and I hope she will be able to identify it. I have included a photo of the local fish vertebra and one of the fossil fish vertebra.
Fish vertebra from Southern California beach. Fossil fish vertebra from South Dakota.In closing I will just say that Laurel and I are looking forward to the surprises that are in store for us this summer in the field. I will do my best to share our experiences each day with text and photos. This method of communication is so new to me and without my daughter Daria's help, it would never materialize. Writing is easy enough, but transferring photos from camera to computer into blog is a challenge. I am much more at ease crouched under a blazing sun, scraping around in the dirt of South Dakota, imagining what life was like 65 million years ago. Thank goodness the rest of my family embraces technology as enthusiastically as I embrace life in the Hell Creek!
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