Trace fossils attributed to waterbird foraging are identified from mudflat successions in the Eocene of Utah. These traces occur in close association with the footprint taxon Presbyornithiformipes feduccii, which purportedly was emplaced by the extinct waterbird Presbyornis pervetus. Four distinct morphologies of foraging traces are identified, which are assigned to four new trace fossil taxa: Erevnoichnus blochi, E. strimmena, Ravdosichnus guntheri, and Aptosichnus diatarachi. These trace fossils are interpreted to record tactile (non-visual) foraging strategies by lake-margin waterbirds searching for prey.

Foraging traces associated with the web-footed avian footprint ichnotaxon Presbyornithiformipes feduccii are described. Four new ichnospecies in three new ichnogenera are established to identify and describe the traces that resulted from foraging behaviors. All four ichnotaxa are, in places, overprinted by P. feduccii footprints and occur either laterally to, or sinuously woven between, P. feduccii trackways and therefore were clearly emplaced by the P. feduccii tracemaker.

Erevnoichnus blochi new ichnogenus new ichnospecies is established for a series of pits, joined by a marginal groove, that are associated with web-footed bird trackways. This ichnotaxon is interpreted to record regular probing/gaping as a waterbird swept its head from side to side searching for food. Erevnoichnus strimmena n. igen. new ichnospecies is established for en-echelon, gently arcuate grooves produced through forward probing by a waterbird searching for food. Ravdosichnus guntheri new ichnogenus new ichnospecies is established for simple grooves with u-shaped profiles produced when a waterbird dragged its bill backwards through the sediment. Aptosichnus diatarachi new ichnogenus new ichnospecies is established for a broad, shallow groove/trough characterized by sinuous margins and a complex, irregular fill. It is interpreted to record thorough bill stirring in an area with common prey.

All four ichnotaxa named herein are interpreted to record tactile feeding behavior by a marginal lacustrine waterbird searching for prey. Their association with Presbyornithiformipes feduccii suggests that the purported tracemaker, Presbyornis pervetus, did not forage solely through filter-feeding but was also capable of tactile foraging for larger prey.