Aurochs \ˈau̇-ˌräks, ˈȯr-ˌäks\ is the singular and plural form. You know, like moose.
This is not a moose
A cow-like beast that can be slaughtered for food. In past revisions, the only source of Raw Aurochs Steak. Currently, they may be hunted for Raw Steak instead, in common with most other wildlife. Under certain circumstances they may attack a player's colonists.
Currently they seem to move around the map until they stumble upon a colony, unless they are hunted.