Institutions and migrations. Short-term versus long-term moves in rural West Africa

This paper is based on fieldwork done in 1992-93 in the Senegal River valley, Sahelian region characterised by heavy out-migration for more than thirty years. As a result of this long history of human displacement, migration has now become a local institution its own. More recently, the introduction of irrigation in an otherwise drought-prone area seems to have reduced the intensity of the phenomenon, but the momentum gathered by local institution of migration means that the decrease of migration rates is likely to be very slow. The present analysis borrows some of its basic concepts from the new institutional economics and should therefore be seen as an illustration of how this perspective, quite effective in describing the complexity of social exchanges in rural societies, helps explain various determinants of migration. We will show, for example, that the two types migration observed (short-term and long-term) respond similarly to common structural and family conditions, and appear to differ mainly when individual variables are taken into account. This feature underlines the crucial opposition between, on the one hand, individual determinants and, on the other, structural factors determined by economic or family characteristics.