Pteranodon only eat fish, but when hungry they do not hunt fish.

I just watched a hungry pteranodon go on a murderous rampage and kill a bunch of meganeura (it was on the ground the whole time, they were flying) but didn't gain any hunger bc of course it doesnt eat them. It just doesnt seem to want to eat unless from a feeder.

In this vein, it could be possible to let them "spawn" fish items to eat when they are in the water, like the aquatics used to do (and maybe still do - can't recall).