FOLLOWING THEIR FOOTSTEPS: REPORT OF VERTEBRATE FOSSIL TRACKWAYS FROM JOHN DAY FOSSIL BEDS NATIONAL MONUMENT, OREGON, USA

John Day Fossil Beds National Monument (JODA) preserves an exceptional geologic record which stretches from the upper Eocene to the upper Miocene (48.4-7 Ma) of Oregon. Within this record are countless well-preserved vertebrate body fossils which JODA is famous for. While great emphasis has been placed into the study of the body fossils of JODA, very little work has been done in the study of the vertebrate trackways recovered from the area. There are only four known vertebrate trackway specimens from JODA which detail the behaviors of at least four separate trackmaker types in two different geologic units. Track types include superimposed feliform impressions and a perissodactyl impression (Turtle Cove Member, John Day Formation, 30 Ma), as well as avian and possible lacertiform reptile impressions (Clarno Formation, 50-44 Ma). We used Agisoft Metashape Professional to produce 3-dimensional and digital elevation models (DEMs) of each impression surface. These models enable remote study and provide for accurate measurement of impression dimensions, pace measurements, and also enable an enhanced resolution of surface features which may be difficult to view otherwise. The Clarno Formation trackways are the only evidence to suggest that both birds and lizards were present during their respective time period, providing a greater knowledge of faunal diversity within the upper Eocene paleoenvironment. John Day Formation trackways also bear resemblance to organisms already known from the Turtle Cove Member fossil record, such as nimravids and tapirs. These JODA impressions are the only vertebrate tracks collected within the region, heightening our understanding of faunal diversity during their respective time periods.