By 1990,5 as many as 2,000 factory units were functioning along the US-Mexico border. Border towns which are industrializing, whether they are at Ruili on the Myanmar-South West China border or along the Mexico-US border, function as a magnet, drawing potential workers from the distant countryside. They employed close to half a million workers—but there was a catch here: most of the workers were women. The history of Mexican migration has shown that most migrants were men, especially in the seasonal agricultural worker sector. Thus, argued Sergio Diaz-Briquets,6 the goal of creating employment for returning migrants or would-be migrants seemed not to have worked. It is believed that large numbers who came to the industrial belt travelled on to the United States.

Guest workers can create a problem for policy-makers back home. There is a growing reluctance worldwide to accept immigrants. The dilemma is posed by the rights and expectations of the host community or the voters where adult franchise is practised and the demands of those who have moved and need sustenance.

‘Respect for the human rights of the asylum-seeker might be in conflict with the understandable concern of resident communities to protect finite resources from unrestricted access to those from without,’ says the summary of an international seminar on environmental impacts resulting from mass migrations.7

Those, who have been environmentally displaced, move because they have no other choice. This has been asserted earlier in this book. Displacements may occur either en masse, following a major disaster such as a cyclone or flood, or in waves and ripples. The latter may be caused by a fall in the availability of common resources and could be triggered by a range of factors including desertification. These causal factors are growing in scale and diversity because of the pressures on our earth. As we have seen population growth is the chief reason. Others include prolonged drought, soil erosion, diminishing water supplies and deforestation, all of which force people to seek livelihoods and homes elsewhere.

Environmental Displacement

Experts have defined five categories of population movement caused by environmental factors:8