The temporal aspect of migration relates both to the distance traversed and the duration of residence at the destination. A typology of migration distinguishes between direction, type, distance and duration of residence essentially with respect to internal migration. The same typology can, with some modifications, be extended to international migration. For instance, the direction is relevant to both internal and international migration; so is the time dimension. The relevance of the distance factor is, however, a function of the size of the country under consideration. As the United Nations (1982) puts it succintly:
Owing to the relatively small size of African states, as compared with those of other developing regions, some immigration that would elsewhere fall into the category of internal movement in Africa occurs across national frontiers.
Thus, movement between Lagos and Maiduguri in Nigeria spanning about 1,700 kilometres is classified as internal migration based on a distance (spatial) criterion while a person moving from Idiroko in Nigeria to Ifoyin in the Republic of Benin -- a distance of about ten kilometres --becomes an international migrant; this also applies to frontier workers where families reside on one side of a national border and commute daily across the frontier to their farms, as between Kenya and Uganda, Ghana and Togo or Nigeria and Benin. As Kumepor and Looky (1974) remind us, and the example can be multiplied:
The distance between most Togolese home towns and their Ghanaian residences is usually not great, in most cases shorter than the homes of Ghanaians from regions such as Ashanti, Brong-Ahafo, and the Northern Region who are resident in Accra. The distance factor makes it easy for most Togolese residents in Ghana to pay frequent visits home while maintaining semi-permanent residence in Ghana.
The Sahelian countries -- Senegal, Mauritania, Mali, Upper Volta, Niger and Chad -- are very poor and are inhabited mostly by nomads, seminomads and sedentary farmers (Marnham, 1979). Among the nomads, the most numerous pastorialists are the Fulani (also known as the Peulh) who live in Niger, Mali, Upper Volta, Nigeria and Senegal. The homelands of some nomadic tribes have been divided by borders, as is the case of the Teda, divided between Chad and the Libyan Arab Jamahariya. In fact the colonial frontiers imposed arbitrarily are a serious hindrance to the free movement of nomads in some situations. Nevertheless, nomads often cross borders between Kenya, Ethiopia and Somalia during the seasonal search for water. In fact, nomads of Somali ethnic stock are found in Djibouti, Kenya, Ethiopia and of course Somalia.
My (1979) observation is pertinent here:
Migration across national boundaries particularly in West Africa, was prominent prior to the attainment of political independence and the emergence of well-defined territorial boundaries; moreover, the consolidation of boundaries has had a minimal impact as most migrants move quite freely, unhindered by 'artificial' frontiers.
This means that many population flows within the continent are not 'entirely international in the traditional sense' (Appleyard, 1981).
Again in West Africa, the frontier, seasonal and short-term migrant workers regard their movements as simply an extension across national boundaries of internal movements and of rural-rural migration. Indeed, it is difficult to establish, in most cases, just when a traveller crosses international borders. The mixture of people, the so-called ethnic groups, can be very fascinating: the Mende-speaking people live in Liberia and Sierra Leone; so do the Vais and Kroos in both countries. Yorubas are found in Nigeria and Benin as are Ewes in Togo and Ghana. Thus Appleyard (1981) notes, that 'there is probably only a fine line between some kinds of clandestine and worker migration (especially on the African continent), and so any attempt to bring rigour to definitions, though commendable, cannot be begun with optimism'. Nevertheless, he recommends that 'there is also a strong case for devising a new typology and classification'.
Another area of interest concerns chain and group migration which are features common to both internal and international migration in Africa. Unlike the case of 'voluntary' migration, which derives mainly from economic factors, the reasons for mass migration, within and across national borders in Africa, are non-economic being related to political and religious factors, and sometimes, natural disasters.
While the cases of mass movement of refugees (victims of war and civil disturbances); expellees (migrants in irregular situation) and pilgrims are special examples, there are instances of group migrations among internal and international migrants. Examples of such movements among internal migrants include the migrant tenant farmers of southern Nigeria. Spontaneous group migrations have also been reported in Ghana, Ethiopia, Kenya and Zambia, resulting from resettlement schemes. As Adepoju (1983) observed:
Group migration among homogeneous communities is not restricted to internal migration but has been prominent in international movements as well. The best known example is that of Nigerians who have migrated to Ghana, Togo, and the Republic of Benin. Groups of Yoruba originate from the same localities in Nigeria and migrate to specific destinations. These migrants usually originate from the same village or town, and often migrate in groups or chains from the home area to the destination.
Owing to the relatively small size of African states, as compared with those of other developing regions, some immigration that would elsewhere fall into the category of internal movement in Africa occurs across national frontiers.
Thus, movement between Lagos and Maiduguri in Nigeria spanning about 1,700 kilometres is classified as internal migration based on a distance (spatial) criterion while a person moving from Idiroko in Nigeria to Ifoyin in the Republic of Benin -- a distance of about ten kilometres --becomes an international migrant; this also applies to frontier workers where families reside on one side of a national border and commute daily across the frontier to their farms, as between Kenya and Uganda, Ghana and Togo or Nigeria and Benin. As Kumepor and Looky (1974) remind us, and the example can be multiplied:
The distance between most Togolese home towns and their Ghanaian residences is usually not great, in most cases shorter than the homes of Ghanaians from regions such as Ashanti, Brong-Ahafo, and the Northern Region who are resident in Accra. The distance factor makes it easy for most Togolese residents in Ghana to pay frequent visits home while maintaining semi-permanent residence in Ghana.
The Sahelian countries -- Senegal, Mauritania, Mali, Upper Volta, Niger and Chad -- are very poor and are inhabited mostly by nomads, seminomads and sedentary farmers (Marnham, 1979). Among the nomads, the most numerous pastorialists are the Fulani (also known as the Peulh) who live in Niger, Mali, Upper Volta, Nigeria and Senegal. The homelands of some nomadic tribes have been divided by borders, as is the case of the Teda, divided between Chad and the Libyan Arab Jamahariya. In fact the colonial frontiers imposed arbitrarily are a serious hindrance to the free movement of nomads in some situations. Nevertheless, nomads often cross borders between Kenya, Ethiopia and Somalia during the seasonal search for water. In fact, nomads of Somali ethnic stock are found in Djibouti, Kenya, Ethiopia and of course Somalia.
My (1979) observation is pertinent here:
Migration across national boundaries particularly in West Africa, was prominent prior to the attainment of political independence and the emergence of well-defined territorial boundaries; moreover, the consolidation of boundaries has had a minimal impact as most migrants move quite freely, unhindered by 'artificial' frontiers.
This means that many population flows within the continent are not 'entirely international in the traditional sense' (Appleyard, 1981).
Again in West Africa, the frontier, seasonal and short-term migrant workers regard their movements as simply an extension across national boundaries of internal movements and of rural-rural migration. Indeed, it is difficult to establish, in most cases, just when a traveller crosses international borders. The mixture of people, the so-called ethnic groups, can be very fascinating: the Mende-speaking people live in Liberia and Sierra Leone; so do the Vais and Kroos in both countries. Yorubas are found in Nigeria and Benin as are Ewes in Togo and Ghana. Thus Appleyard (1981) notes, that 'there is probably only a fine line between some kinds of clandestine and worker migration (especially on the African continent), and so any attempt to bring rigour to definitions, though commendable, cannot be begun with optimism'. Nevertheless, he recommends that 'there is also a strong case for devising a new typology and classification'.
Another area of interest concerns chain and group migration which are features common to both internal and international migration in Africa. Unlike the case of 'voluntary' migration, which derives mainly from economic factors, the reasons for mass migration, within and across national borders in Africa, are non-economic being related to political and religious factors, and sometimes, natural disasters.
While the cases of mass movement of refugees (victims of war and civil disturbances); expellees (migrants in irregular situation) and pilgrims are special examples, there are instances of group migrations among internal and international migrants. Examples of such movements among internal migrants include the migrant tenant farmers of southern Nigeria. Spontaneous group migrations have also been reported in Ghana, Ethiopia, Kenya and Zambia, resulting from resettlement schemes. As Adepoju (1983) observed:
Group migration among homogeneous communities is not restricted to internal migration but has been prominent in international movements as well. The best known example is that of Nigerians who have migrated to Ghana, Togo, and the Republic of Benin. Groups of Yoruba originate from the same localities in Nigeria and migrate to specific destinations. These migrants usually originate from the same village or town, and often migrate in groups or chains from the home area to the destination.