WORLD MIGRATION REPORT 2015 Migrants and Cities: New Partnerships to Manage Mobility
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to be at the centre of national and global migration and development agendas. This has been a core message of international debates on migration since the UNDP Human Development Report 2009 on human mobility and development. By examining how migration affects well-being, WMR 2013 drew attention to migrants’ human development and its significance in policy debate. Migrants may be part of the challenge, especially during and after humanitarian crises, but they can also be part of the solution. As members of a global diaspora, migrants can act as bridge-builders, traders, business partners and humanitarian support between cities and countries. The economies of cities that have been built up by remittances of migrant workers are often more closely linked to the economies of the host country than the home country (Subohi, 2009; Klaufus, 2010). As cities plan for and manage the challenges of population growth (also from inflows) and increased sociocultural diversity, they need to include migrants in their planning and management for resilience.
1.2 DEFINITIONS AND TERMINOLOGY
Urbanization is defined mostly in demographic terms as the increasing share of a population that is living in urban areas. This increase can be attributed in general to three factors: natural population growth, net rural-to-urban migration, and the progressive extensions of urban boundaries and creation of new urban centres. Very often, urbanization is primarily the result of migration. This is shown by the fact that fertility rates in urban areas tend to be lower than those of rural areas. This means that natural population growth of urban areas (the first factor mentioned above) is usually lower than that of rural areas. Furthermore, the extension of urban boundaries and creation of new urban centres (the third factor above) can also be often due to migration. Additionally, the term “urbanization” frequently refers to a broad rural-to-urban transition involving changes in population, land use, economic activity and culture. For example, on the periphery of urban centres, land becomes “urbanized” as it is developed for housing or manufacturing facilities and to where people move in order to live and work. However, these changes do not occur simultaneously, and the distinction between alterations in rural–urban economic activities and those involving cultural norms becomes less clear (McGranahan and Satterthwaite, 2014). Urbanization and urban population growth are often conflated yet are still distinct concepts. Urban population growth is defined as the increase in the proportion of the urban population over time as part of the whole population. If the total population is not changing while the urban share is increasing, all urban population growth is the result of urbanization. Hence, in such simplified cases the rate of urbanization is equal to the rate of urban population growth. In most urbanizing countries in Asia and Africa, however, the situation is not so simple since the overall population is also growing. The fertility rates in these countries still remain higher than those of other regions where urbanization has slowed down and fertility rates are lower. Therefore, the contribution of migration to the urban population growth of Asian and African countries is relatively lower compared to natural population growth attributable to fertility rates. In Africa, migration only accounts for about one third of urban population growth whereas in Asia, the contribution of migration to urban population growth is higher than this due to a higher urbanization rate in Asia than in Africa (Tacoli, McGranahan and Satterthwaite, 2014).