There seems to be a bug with the bison calves.
Somehow my bison calf couldn’t leave this one tile.
And as it got baby cows they couldn’t leave the tile either.
So i had to kill the bison 
And get a new bison calf.
3 Likes
maybe It’s not a bug . As you know bison can’t follow people ，and it can only walk about on the same terrain . You put this bison on a small desert . Therefore it can’t go anywhere , and the calves can’t leave it’s mum .
4 Likes
It looks like that is exactly what it is.
3 Likes