Otherwise, those survivors in the camp who tried to domesticate ancient creatures wouldn't have repeatedly failed, since most creatures, as long as they are trained from a young age, can basically be domesticated into livestock.
And this accidental discovery of an ancient creature's nest and its young had all the members of the Hunting Team gobsmacked.
Despite their frequent excursions to hunt ancient creatures, just like the situation mentioned before, these creatures were akin to the monsters in games; even if one were to kill all the monsters in this area.
But given enough time, the monsters in this region would respawn.
Hence, their hunting was primarily confined to certain fixed areas, for two simple reasons; first, they were familiar with the terrain, and second, because the designated areas wouldn't have large ancient creatures they couldn't handle.