Only fragmentary remains of dinosaurs have been found in Delaware. All of these have come from the Chesapeake and Delaware Canal, mainly from the spoil piles created by the dredging of the Canal. Various nature groups in Delaware lead trips to the Canal for collecting. Most of the fossils found are those of marine invertebrates (primarily bivalves and gastropods with some remains of sponges, ammonites, and belemnites).
These fossils date to the late Cretaceous (97 to 65 million years ago) and come from the marine sediments of the Marshalltown and Merchantville Formations. Of the dinosaur remains, none have been complete enough for genus and species identification. At least two hadrosaurid (duck-bill dinosaurs such as Maiasaura) teeth have been found. Several toe bones of ornithomimosaur (small and agile theropod predators that look something like plucked ostriches with long tails and arms) dinosaurs and a partial hadrosaurid vertebra have been recovered.
In addition to the dinosaur remains, other vertebrate fossils that have been recovered include: teeth of the marine reptiles Mosasaurus, Globidens, and Tylosaurus; part of a jaw and plates (scutes) of the giant crocodile Deinosuchus; a pleisiosaur vertebra; remains of bony fishes; and shell fragments of the turtles Trionyx, Toxochelys, and other forms. One of the most unique remains found in Delaware is that of a neck bone and a wing bone from a pterosaur (a flying reptile).
Sources of Information
There are many excellent books on dinosaurs available at your local library. A very good book on collecting dinosaur fossils in this region is one entitled "Dinosaurs of the East Coast" and was written by David B. Weishampel and Luther Young. It was published in 1996 by The Johns Hopkins University Press. The book is very thorough in describing dinosaur fossil collecting localities from all along the East Coast of North America, the kinds of dinosaurs to be found, and the habitats and lifestyles.
Another fine book on local dinosaurs is written by William B. Gallagher and is entitled "When Dinosaurs Roamed New Jersey." It was published by Rutgers University Press in 1997. It describes the dinosaur fossils that have been found in New Jersey as well as some information about those from Delaware. The information of dinosaurs from Delaware given above comes from these books.
For information regarding the Cretaceous fossils from Delaware, the following are available from the Delaware Geological Survey:
- Open File Report No. 21
"A Guide to Fossil Sharks, Skates, and Rays from the Chesapeake and Delaware Canal Area, Delaware" written by E.M. Lauginiger and E.F. Hartstein in 1983 and reprinted in 1995.
- Special Publication No. 18
"Cretaceous Fossils from the Chesapeake and Delaware Canal: A Guide for Students and Amateurs" written by E.M. Lauginiger in 1988.
- Special Publication No. 19
"Delaware: Its Rocks, Minerals, and Fossils" written by D.C. Windish and T.E. Pickett in 1980 and reprinted in 1991 and 1992.
- Special Publication No. 21
"Geology and Paleontology of the Lower Miocene Pollack Farm Fossil Site, Delaware" edited by R. M. Benson in 1998.