The Teda are, by numerical majority and by cultural preference, nomadic pastoralists. They have herds of goats and, in some areas, camels. As is the case throughout North Africa and the Middle East, the actual degree to which any sector of the population relies on migratory herding for its subsistence, however, varies regionally with social conditions, climate, and terrain. Most of the Tibesti is so barren as to require migration for pasture, and since herding is not a self-sufficient subsistence mode, seasonal migration is also necessary for date harvesting. Even in the best years, however, these two activities do not produce an adequate diet. In the north-central and northeastern Tibesti, there are areas of arable land where sedentary and semisedentary sectors of the population cultivate vegetable gardens, cereals, groves of palm and fruit trees, grapes, and some cotton. Trade between the pastoral and agricultural sectors is essential to the diets of both, whether it be carried out between social units that are almost exclusively migratory or entirely sedentary, or accomplished by division of labor within a social unit whose members exploit both pastures and arable lands. Thus, there is a continuum of patterns of community land use, mobility, and subsistence strategies, with a stated preference and higher status for the end of the continuum that is most exclusively nomadic pastoralism.