A few specimens preserve actual stomach contents. Unfortunately, none of these preserve the skull, so direct correlation between their known diet and snout/tooth shape cannot be made. "Eoalulavis" was found to have the remains of exoskeletons from aquatic crustaceans preserved in its digestive tract, and "Enantiophoenix" preserved corpuscles of amber among the fossilized bones, suggesting that this animal fed on tree sap, much like modern sapsuckers and other birds. The sap would have fossilized and become amber. However, more recently it has been suggested that the sap moved post-mortem, hence not representing true stomachal contents. Combined with the putative fish pellets of "Piscivorenantiornis" turning out to be fish excrement, the strange stomachal contents of some species turning out to be ovaries and the supposed gastroliths of "Bohaiornis" being random mineral precipitates, only the "Eoalulavis" displays actual stomach contents.