While out on a rescue we stumbled upon this chap who was happily playing some music in the woods on his flute.
If you look closely, the squirrel's flute is in fact a bone and not a stick. as we first thought! Wild animals need calcium just like us, and one way of absorbing it is to chew on bones. The squirrel instinctively knows how much it needs and will eat a balanced diet by doing this from time to time. It's common to all the animal kingdom, even herbivore.
Chewing on a bone also helps to wear down their teeth, which continuously grow throughout their lives - up to 15 centimeters a year. If they didn't keep their teeth in good condition, they would overgrow and the squirrel would be unable to eat at all.