TO BE (EATEN) OR NOT TO BE (EATEN): THAT IS THE QUESTION. FOSSILIZED FISH TRAILS FROM THE NEWARK SUPERGROUP OF EASTERN NORTH AMERICA

Given the dearth of herbivore tracks in the early Mesozoic, dinosaur-dominated ichnofaunas of the Newark Supergroup in Eastern North America, some researchers have argued that a major food source for carnivores was fish. Indeed, this makes sense given the large number of fossilized fishes found in rocks representing deep lake deposits. However, no unequivocal swim tracks are known from these rocks to indicate that the theropods were swimming into deeper parts of the lake to fish. Rather, tracks are abundant in parts of the lakes that were shallow enough such that the animals were not being buoyed, and thus they left complete tracks produced by the plantar surface of the foot. Further, there are few, mostly fragmentary, fossilized fish found in shallow lake deposits. Surprisingly, fish trace fossils also appeared, until recently, to be rather uncommon. Taken at face value, the lack of swim tracks and the paucity of fish fossils in shallow water deposits could be taken to indicate that the dinosaurs were not consuming fish on a regular basis. Recently, however, fossilized fish trails have been reported from shallow lacustrine rocks at three localities within the Newark Supergroup, making the likelihood of theropod piscivory in this region more likely. Here, I report yet another occurrence of fish trails, this one at a classic dinosaur track site in Connecticut from which Edward Hitchcock collected numerous theropod dinosaur tracks. I review what is currently known about such trails in the Newark Supergroup and suggest that, once local geologists have the proper search image, such traces will be recognized on a more regular basis.