The animals in Wurm Online aren’t just there to be captured and/or killed by players. They’re meant to act in a plausible manner, avoiding players and looking for food, until players hunt and/or capture them. But as the latest development dispatch explains, some of that code is causing problem by giving animals small points of heavy clustering while restricting movement in other ways.
Essentially, as animals avoid settlements, it was possible for large groups of animals to wind up concentrated in very small spaces away from where players would encounter them. The game’s approach to pathing could also lead to certain animals being unable to move outside of a small corner of a pen, which is also undesirable. New systems will be rolling out to ensure that animals are more willing to spread out and able to path more naturally when confined; you can read about all of the technical details in the full entry.