The major cause of voluntary movement of populations between and within national borders in recent years is rooted in the initial and growing disparity in development between and among states. The causes and consequences of such movement have economic, political, social and demographic dimensions (Heisel, 1982). Migration, by its very nature, involves at least three major actors: the migrant, the area or country of origin and the area or country of destination. While internal migration, in principle, implies movement of people within a geographically defined territory unrestricted by legal constraints, an international migrant is invariably confronted with a series of-sometimes complex -- regulations relating, at first, to exit from the country of origin, and later, entry into, residence within, and exit from the receiving country.

In Africa, as elsewhere in the developing regions, the historical evolution and stages of political development are crucial to an understanding of migration in general, the distinction and linkages between internal and international migration, their causes and policy issues. Of particular relevance in the African context are the effects of the demarcation of national boundaries, the emergence, since the early 1960s, of independent nation-states and especially the setting up of regulations governing immigration. These have introduced a subtle distinction between internal and international migration both of which once involved free movement across wide areas of Africa and, in the case of international migration, between legal and illegal immigrants. These linkages are analysed below against the background of the causes of population movements and the policy responses to them.

The migration phenomenon in Africa can be better understood within the context of political and historical evolution of African societies. The effects of colonization and decolonization on the economy and indirectly on migration are most visible when examined in the context of the pre-colonial, the colonial and post-colonial era. In the pro-colonial era, population movements in Africa were associated largely with the prevailing sociopolitical and ecological conditions, especially internecine warfare, natural disasters and the search for farm land or colonization. The movements were, as a result, unstructured, occurred in groups, and the migrants were demographically undifferentiated (Adepoju, 1979).

Colonial rule paved the way for peace and political stability; movements hitherto associated with internecine warfare ceased or were reduced but have since again surfaced, according to a different pattern, in the form of refugees as independent nations engage in war, as in the case of the Ethiopia/Somalia conflict, the internal strife in Chad, Angola, Uganda and Nigeria and the liberation war in West, Central and South Africa. Natural disasters still persist: the drought in the Sahel region of West Africa and parts of East Africa dislodged many thousands of people, including women and small children. The search for new or fertile land still continues and the number of the landless poor has increased considerably, notably in East Africa.

The introduction of various coercive measures and incentives during the colonial era was largely designed to secure labour to meet the growing demands of the mines and plantations. In West Africa, the French colonial administration resorted to various forms of labour conscription in, for instance, Upper Volta and Mali. In eastern and southern Africa, migrants were not directly coerced; rather, a series of strong economic policies were used to induce labour of the required quality and quantity to work in the mines and plantations.

In South Africa, in particular, workers' families have, since 1963, been prevented from living with them at the work-site; this, coupled with low pay and poor working conditions, initially led to high labour turnover. In fact, the conditions favouring such a situation were designed to maintain low subsistence wages. Besides, when the arduous tasks reduced productivity of workers, who were hired on contract for periods of not more than two years, the overtaxed and exhausted workers were replaced in order to maintain, indeed increase, productivity.

Here lie the roots of the temporary, target migration pattern, which involves international migration, in the African context: workers circulate between home and the mines, disillusioned by the poor earnings and inadequate welfare services. In certain cases, workers prefer to return home permanently rather than remain in the mines and plantations where working conditions are, in fact, dehumanizing. In this context, the explanation of the temporary nature of migration in eastern and southern Africa in terms of target needs is inappropriate. The underlying factors can be traced to the organization of tasks, living and working conditions not normally conducive to decent living. Thus, as conditions of work improve, workers are more stable and 'committed' and indeed attract further manpower, as was the case in Zambia, United Republic Cameroon (in the plantations of former Spanish Guinea) and Nigeria. By the time of independence, these migrations became institutionalized, but by then various restrictive practices relating to family reunions, residence and contractual labour systems in West and East Africa had been removed; however, these are still enforced, perhaps even more rigorously, in South Africa.

Currently, a series of external constraints on the internal development strategies in Africa invariably affect the opportunity structure of the local population, especially in rural areas. The policies of international corporations with regard to investment which buttresses national development strategies exert tremendous impact on the internal political, social and economic organization, especially with respect to location and types of employment opportunities, incomes and living conditions which have in turn influenced both internal and international migration in Africa.

The growing body of literature on migration both internal and international tends to reach a consensus that economic considerations are of primary importance in the decision to migrate, in that people migrate ultimately to improve their economic well-being. If this is the case, then migration can rightly be perceived as a response -- sometimes exaggerated -- to economic incentives arising largely from disequilibria between and within sectors of the economy and between countries and regions.

These postulates raise two questions: What factors account for -- indeed accentuate -- such structural equilibria? How responsive is migration to such imbalances between and within countries? The last question raises the issue not only of the role of information networks in transmitting impulses about the range of available opportunities, but also the ease of migrating in spite of intervening obstacles and barriers: controls and regulation governing migration within and across national frontiers. Here, a subtle distinction has to be drawn between internal and international migration. An international migrant in a regular situation is expected to conform to a set of requirements governing entry into, and residence within, another country. Only a few African countries have well-articulated immigration laws and even fewer enforce such laws rigidly, the notable exception being the Republic of South Africa; and at any rate, these regulations are usually flouted by migrants deliberately or out of ignorance of existing laws (Conde, 1979).

Internal migration takes place in large part in response to imbalances between the regions of a country, the dominant direction of such movement being dictated by the locational bias of employment-generating projects. Thus, where both private and public investment is concentrated in the major (often the capital) city as is the case in most African countries, the dominant migration stream will no doubt be directed towards the capital. However, where plantations, mines and other enterprises are located in rural areas and offer readier employment and other opportunities, a substantial flow of intra-rural migration is to be expected, as is the case in the United Republic of Cameroon, Kenya and others.

In like manner, international migration signifies, to a large extent, inequalities in development, employment opportunities and especially income and living conditions between countries, particularly between the developed and developing countries. In the absence of strict restrictions on entry, and where information flow is both rapid and effective in disseminating the range of available opportunities in different locations, migration is expected to respond (quickly) to such positive, often exaggerated, signals. However, since international migration has political, socioeconomic and demographic consequences for both the sending and receiving countries, perhaps more than does internal migration, a series of regulations has been set up and enforced to screen, and where necessary restrain, the massive flow of immigrants into the affected countries.

It is obvious, then, that both internal and (voluntary) international migration, in general, derive from the same set of fundamental causes: however, the limitations imposed on international migration are greater, or more easily enforced. This in fact explains, for instance, why the volume of internal migration is, according to Zachariah and Conde (1981), twice that of international migration in West Africa. The linkage between both internal and international migration and factors which influence both also imply -- again in the context of West Africa -- that:

in general, internal migration is an extension of external migration. The overall direction was the same: from the interior parts of a country to the coastal areas. There is an overall negative relation between emigration and internal migration and a positive relation between immigration and internal migration. The internal migration rate was low in Upper Volta and Togo where lifetime emigration rates were high; it was high in Ghana, the Ivory Coast and Senegal where the emigration rate of nationals was relatively low ... [Thus] areas with a high in-migration rate had a high immmigration rate.

Conceptually, international and internal migration are complementary and can indeed supplement each other. First, as speculated above, both derive from a complex of interrelated social and economic factors, but are primarily related to the migrants' search for greater well-being. This, of course, does not include those displaced by natural disaster (drought, famine) or those fleeing from war or political oppression (refugees), except for the so-called economic refugees. Again, from a policy perspective, development normally has the effect of initially stimulating migration -- both internal and international -- in the short run. In the long run, however, one viable policy instrument to restrain or retain a large number of (potential) emigrants from poor to rich countries or to attract them back home is sustained development in the labour-exporting countries. This strategy is based on the notion that people migrate in large part when they are unable to satisfy their aspirations within the existing opportunity structure in their locality or country. The policy-relevant question is: How can development be structured to provide local alternatives to international migration? This becomes especially critical for countries like Botswana, Lesotho and Swaziland that depend heavily on the export of labour to the mines of South Africa. An obvious example in West Africa is Upper Volta which is also traditionally a labour-exporting country. (This aspect is elaborated below.)

The reasons associated with international migration are not solely economic. As Speare (1974) suggests, 'in international migration, political factors are often more important than economic factors'. Demands for adjustment of boundaries arbitrarily drawn by the colonial administration and which cut across economic and homogeneous ethnic groups, 'to accommodate the socio-cultural realities of the countries concerned and to regroup the populations of ethnic groups arbitrarily assigned to different countries', have led to war (Adepoju, 1982). An obvious example is the case of Somalia and Ethiopia, or less dramatically between Nigeria and the United Republic of Cameteen. The result, in all cases, is hundreds of refugees and displaced persons.

The temporal aspect of migration relates both to the distance traversed and the duration of residence at the destination. A typology of migration once outlined by the author (Table 1) 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.

In the absence of official channels of assistance, migrants in Africa rely on the network of social relations -- friends, relatives, townsfolk -- to give the signal for migrating, provide accommodation on arrival and assist in securing employments.

Conde (1983) documents an illuminating example of this feature among 'illegal' immigrants from Mali, Senegal and Mauritania resident in France:

Clan solidarity is fully operative; brothers, uncles and cousins sheltering their brothers, cousins and nephews etc.... Various communities are found in the hostels.... Each community tends to regroup. What distinguishes the black community most, especially the Soninkes and Toucouleurs, is that they re-group by village of origin.... Each immigrant retains his village status.... Assistance is provided from the community found to people in need, those who have not yet found jobs, or are unemployed.

The observation above and others like it show that African migrants --internal and international -- retain a prototype of the sociocultural structure of the home community and regard their place of current (temporary) abode as an extension of the 'home' community. The observation by Zachariah and Conde (1981) that emigration is regarded simply as an extension of internal migration within the continent can, in view of Conde's remarks, be extrapolated to the situation outside the African region.

Rural migration in Africa is an alternative to rural-urban migrations in view both of the characteristics of the migrants (who are predominantly uneducated and unskilled people in the middle adult ages) and the features of the rural economy. The diversity of ecological features, the cyclical demand for labour in the region, the varying local resources and the location of agricultural projects especially in the United Republic of Cameroon, Kenya, the United Republic of Tanzania serve as major pull factors for migration directed at the rural sector. In West Africa, as well, most migrants originate from and move to rural areas. This observation also applies to Kenya where Livingstone (1981) reported that the major migratory flow is, in fact, rural-to-rural. This is also the case in Ghana as the 1970 census indicates: 60 per cent of internal migration is of the rural-to-rural type.

Just as rural-to-rural migration serves as a viable alternative to rural-to-urban migration for a large proportion of migrants in Africa, a sizeable proportion of international migration is also directed to rural areas at the destination. The case of the frontier migrant workers is the most glaring: these cross-national borders regularly to work in rural areas of the neighbouring country. In Zambia, for instance, 60 per cent of the African immigrants in 1963 were resident in the rural areas. Those who went to the urban areas -- 32 per cent -- consist mainly of skilled workers (Ohadike and Tesfaghiorghis, 1974). In 1960, two-thirds (67 per cent) of foreign nationals in Ghana were living in rural areas; this percentage declined slightly to 65 in 1970 (Zachariah and Conde, 1981).

Refugees also follow this pattern. The majority of refugees in Africa are from a rural background, and most of them live in rural areas in the receiving countries either in organized rural settlements -- as in Sudan, the United Republic of Tanzania, Somalia -- or amidst the local population as is the case in Somalia. In fact, it is estimated that about 60 per cent of Africa's refugees live outside organized settlements and camps amongst the local population (Adepoju, 1982 and references cited there).

This conclusion is not totally valid: there are a few exceptions. Sudan, where an estimated 50 per cent of the refugees settled in urban areas, is reputed to have the largest urban refugee population in Africa. In general, refugees in Africa especially Sudan, Djibouti and the United Republic of Tanzania join internal migrants in moving either to urban or rural areas and compete for the available job and other opportunities there. It has also been documented that in Liberia, 5 per cent of the population aged 10 years and over in 1974 were immigrants; of these 64 per cent lived in the urban areas.

In sum, immigrants including 'refugees' in Africa compete for the limited wage employment in both urban and rural sectors; some of them fill the positions vacated by the nationals, who have themselves emigrated abroad. In addition, internal migrants from rural areas compete for such positions in the towns from which nationals previously emigrated abroad in search of superior economic and other opportunities. In the United Republic of Cameroon, for instance, where the recent shift from ruralto-rural to cityward migration is due largely to the low wages in the plantation areas, the plantation labourers who migrate to towns are being replaced by Nigerian immigrants, who later engage in trade and commerce in the towns, and sometimes in rural areas (Adepoju, 1983). Conde (1979) also gives an illuminating example of this pattern in Algeria and Tunisia, where rural migrants take up jobs which are vacated by emigrants of urban origin who had earlier migrated to France and in West Africa by emigrants from Upper Volta and Mali to Gabon.

A series of economic and political factors influence the opportunity structure in a country and, indirectly, the tempo and direction of migration -- internal and international. When the economy of a country is revitalized and employment opportunities improve considerably, nationals who had earlier emigrated to other countries could be attracted back home, as in the case of Italy and Greece. The logical corollary -- that deteriorating economic situations have turned labour-importing into labour-exporting countries -- becomes relevant to the situation in Ghana up to 1970 a major immigration country in West Africa. Immigrants were attracted to Ghana's cocoa farms and diamond mines from Togo, Nigeria, Upper Volta and Mali. Besides, there was a considerable amount of interregional migration within the country (Zachariah and Conde, 1981). However, the deteriorating economic and political situation forced a substantial proportion of the adult population, including interregional migrants to emigrate, especially to Nigeria and beyond Africa. Today, Ghana is a country of emigration of both skilled and unskilled labour, a situation that is unlikely to be reversed for the next decade.

In Zambia, for instance, skilled labour, Europeans and Africans alike, was imported at high cost, to manage the country's industries and copper mines. The proportion of immigrants in the labour force peaked around 1960: by then they constituted 24 per cent of the labour force in the 1960-64 period (Ohadike and Tesfaghiorghis, 1974); this declined to 19.9 per cent in 1966. Since independence in 1964, the Zambian Government moved rapidly to promote the indigenization of jobs in the country. As Ohadike and Tesfaghiorghis (1974) reported:

Political independence in Zambia and in the neighbouring countries of origin of the immigrants has introduced economic and legal constraints on the exchange of migrants between countries. In Zambia, visa and work permit regulations are in operation, while in the sending countries, political independence has ushered in alternative and competing economic opportunities which negatively affects immigration to Zambia.

That is, the post-independence social and economic development in the neighbouring countries whence came the immigrants have helped to check or reduce the inflow of immigrants to Zambia. Concurrently, the availability of alternative employment and related opportunities in the home countries encouraged the return home of migrants while Zambians took over some of the jobs.

Nor are the reasons solely economic: there are also political dimensions. Apart from the efforts of national governments to tighten up on free border crossing by introducing visas, passports, national currencies and various forms of immigration checks, a series of recent political developments have greatly curtailed international labour migration, especially in East and Southern Africa. For instance, Zambia and the United Republic of Tanzania especially, in pursuance of their policies against apartheid, prohibited their nationals from emigrating as labourers to the mines of South Africa.

Before independence, Zimbabwe and Mozambique were among the major suppliers of migrant workers to the Republic of South Africa. Mozambique restrained emigration of nationals to South Africa shortly after independence. Also, Zimbabwe effectively prevented a migrant labour supply to the mines in South Africa and actually closed down all labour recruitment offices in the country. Earlier, in 1974, as a result of the Francistown aircraft disaster in which 82 migrant recruits were killed, the Government of Malawi prohibited such recruitment but allowed those already in South Africa to complete their contracts (Elkan, 1978).

The governments of Botswana, Lesotho and Swaziland are increasingly worried about the adverse effects of extreme dependence on the export of (migrant) labour to the South African mines, all the more so in a situation where the demand for foreign labour in South Africa has been declining gradually, due principally to growing unemployment there. The so-called internalization policy, the danger of continued dependence on foreign labour and certain legislative changes have recently enhanced the demand for local labour. At the same time, rising unemployment especially in the industrial sector has forced the black population 'grudgingly' to take up jobs as gold-miners -- the least desired occupation (Stahl, 1982) -- thereby filling the gap resulting from the shortage of migrant labourers from the traditional labour-supplying countries. This trend makes it highly essential for the major labour-exporting countries -- Botswana, Lesotho and Swaziland in Southern Africa -- to pursue vigorously strategies to stimulate employment opportunities in order to reduce emigration of their nationals. A similar recommendation applies to Upper Volta and Mali: in all cases, appropriate employmentoriented development strategies could provide local alternatives to international migration.

* This article, which appeared in the ISSJ, Vol. XXXVI, No. 3, 1984, was written when Aderanti Adepoju was professor at the University of Ife, Nigeria.

Legend for Chart:

Legend for Chart:

A - Classification by national frontiers
B - Direction
C - Type
D - Distance travelled between origin and destination, Short
E - Distance travelled between origin and destination, Medium
F - Distance travelled between origin and destination, Long
G - Time dimension (duration of residence at destination),
    Short-term (seasonal)
H - Time dimension (duration of residence at destination),
    Medium-term
I - Time dimension (duration of residence at destination),
    Long-term
J - Time dimension (duration of residence at destination),
    Permanent

A            B
             C
             D
             E
             F
             G
             H
             I
             J

Internal     Rural-to-rural
             Rural-to-urban
             Urban-to-urban
             Urban-to-rural

             Colonization return migration
             Direct step migration
             Direct step migration
             Colonization return migration

             Moves corresponding to the size of the smallest
              administrative unit

             Moves corresponding to the size of localities
              within a region, state of province

             Moves beyond the region state or province

             Residence of less than two years

             Residence of two to ten years

             Residence of over ten years can be considered
              long-term

             Residence of over twenty years can be considered
              permanent

References

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----- 1982. 'The dimension of the refugee problem in Africa'. African Affairs 81 (322).

----- 1983. 'Issues in the study of migration and urbanization in Africa south of the Sahara'. In P. A. Morrison (ed.), Population Movements: Their Forms and Functions in Urbanization and Development, Liege: IUSSP. (Ordina Editions.)

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CONDE, J., 1979. Migration in West Africa: Some Considerations. Paris, OECD. Mimeo.

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HEISEL, D. F., 1982. 'Theories of international migration'. In International Migration in the Arab World. Proceedings of an ECWA Population Conference in Nicosia. Beirut: UNECWA.

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MARNHAM, P., 1979. Nomads of the Sahel. Report No. 33 (rev. edn). London: Minority Rights Group.

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PRYOR, R. J., 1978. The interrelationship between internal and international migration, with some evidence from Australia'. In Solicited Papers: Conference on Economic and Demographic Change: Issues for the 1980s (Helsinki 1978). Liege: IUSSP.

SPEARE, A., Jr., 1974. 'The relevance of models of internal migration for the study of international migration. In G. Tapinos (ed.), International Migration. Proceedings of a Seminar on Demographic Research in relation to International Migration. Paris: CICRED.

STAHL, C. W. 1982. 'Recent changes in the demand for African labour in South Africa and future prospects'. In F. de Vletter (ed.), Labour Migration and Agricultural Development in Southern Africa.' Rome: FAO.

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ZACHARIAH, K. C., CONDE, J., 1981. Migration in West Africa.' Demographic Aspects. Oxford: Oxford University Press for the World Bank.

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By Aderanti Adepoju[*]