Often times animal predators are detoured by wooden fences just as effectively as 10 foot tall, 3 foot thick stone walls. You only build the later if you enemy is a bit more tenacious then an animal predator.
> Often times animal predators are detoured by wooden fences
Heck, often they're repelled just by the sight of fire or a solitary guard.
More often than not the less-timid ones just scavenge human scraps, return, and start to hang out. This is how dogs became domesticated many thousands of years ago...
