What did the fisherman find in the mouth of this bass?

duck in bass mouth

I found this on Reddit, where the user said he tried to get his fishing lure back from the mouth of bass he had caught and just happened to notice the bass had recently eaten a baby duck... usually when you look into a fish's mouth you'd expect to find an isopod / louse  X but a baby duck? That's gold.

Poor ducks in general though eh? Here's one getting eaten by a gull and a cheeky heron going for.... gold.