What famous book was banned in 1931 for the way it portrayed animal behavior?

Probably Bambi, By Felix Salten. It was out at the time. Hunters are shown in a negative light, and the story is wholly from the viewpoint of the animals. It has a sort of realistic context- animals die, are shot by hunters, or lost in forest fires. This is serious drama, not laughable Cartoons like Mickey Mouse of Bugs Bunny, so it would be taken more seriously. going deeper it tends to indict Mankind, there are no positive human characters in the Forest King"s saga.