Nomadic Berbers inhabit southern Morocco (Ait Atta) and southern Tunisia. First of all, their presence is more visible on the southern edge of the Sahara (especially its Sahelian section) than in the Maghreb portion of the Sahara because of the long-standing and widespread seden-tarisation policy in North Africa. Furthermore, all of the nomadic groups, without exception, are trans-national. Herd composition is also extremely varied.