PRELIMINARY PALEOENVIRONMENTAL, PALEOECOLOGICAL, AND TAPHONOMIC COMPARISON OF TWO NEW MASTODON SKELETONS FROM THE LATE PLEISTOCENE OF NEW YORK STATE

Two relatively complete mastodon skeletons (Mammut americanum) were discovered in the fall of 1999 in New York State, one near Watkins Glen in Chemung County and one in Hyde Park in Dutchess County. Both finds were fully excavated and the resulting materials are now housed at the Paleontological Research Institution in Ithaca. The two finds show similarities and differences that may illuminate the late Pleistocene environment across upstate New York. Both skeletons were found in glacial kettle ponds with very similar stratigraphy. The bone layer in each case was located between a lower clay/marl layer and an upper peat layer. Preliminary analysis of macrofossil floral remains from the Chemung site shows over 10,000 years of deposition including at least 19 tree species plus rhizomes; the Hyde Park remains cover less time, but include 7 boreal tree species and charophytes. Preliminary tree-ring analysis has included building floating chronologies for spruce, fir, hemlock, pine, and oak. C-14 dates of wood from both sites are in progress. The Chemung find appears to include bones of at least two proboscidians; one is much more complete than the other; one may be a mammoth. The bones are abraded in a manner suggestive of trampling by other animals. Although both tusks are present, the skull is represented only by small fragments. The Chemung find has been radiocarbon dated at approximately 12,100 ybp. Also present at the Chemung site are bones of muskrat (Ondatra zibethicus) and the extinct stag moose (Cervalces scotti). The Hyde Park find represents a single, very complete and very well preserved animal. At least 85% of the skeleton is present including the complete and unbroken skull. Bone surfaces are only slightly scratched. The Hyde Park skeleton has been radiocarbon dated at approximately 11,500 ybp. Freshwater mollusks, ostracodes, insects, and diatoms from the site are consistent with a northern boreal climate.