This must be payback for us harvesting their delicious anal glands all those years ago.
https://www.npr.org/sections/thesalt/2014/03/26/293406191/do...
https://www.npr.org/sections/thesalt/2014/03/26/293406191/do...
> Beaver food flavoring doesn't actually come from the animal's anal gland but from another organ next to it, called the castor sac.
I still wouldn't try it, myself.
You're eating beaver back sac.