A club member took his sport plane up a couple years ago. It was flying odd at times, but he thought it was the turbulence. He really wrung the plane out, was having a good ol' time.
After he landed and took the wing off, he found blood & guts all over! Turns out a mouse had gotten in and was maybe trapped so couldn't get out. The high G-loads blew it open and spread the guts all around. Quite the mess to clean out. Ewww...,
I originally thought this would be about flying a full-size plane with 500 canarys. If the canarys all took flight at the same time, would the weight change? A conundrum.