While roots and berries are capable of sustaining any
individual for a long time, its no real replacement for those
who lust after the taste of flesh. The wilderness is inhabited
by many creatures, whose flesh is very edible. Catching these
creatures is a challenge indeed however. The best way to catch
these types of creatures is to trap them. Most of the time they
are fleet of foot and cannot be simply caught and killed with 
a sword. Simple rope traps, and other means allow one to catch
his prey, easily and cleanly. A skilled hunter can live forever
on his own. Of course once the prey is caught preparing it
is another task, maybe if you could cook it over an open fire...