International migration under the microscope

We applaud Willekens et al. (27 May 2016) for highlighting our incomplete knowledge of international migration and for suggesting useful priorities for training and for data collection, availability, and modeling. We agree that this work is hindered by “fragmentation … along disciplinary lines” but argue that integrating the environmental context, causes, and consequences into migration research, teaching, and policy is necessary to understand international migration holistically.

Researchers increasingly recognize the environmental drivers of migration (1, 2), but we know much less about the environmental consequences, including how those consequences might, in turn, influence migrants themselves. Migration can affect the environment of the origin, the destination(s), and the migration route. Vegetation, biodiversity, water, and soils can be altered, influencing ecosystem function and human welfare. Effects along the route may be particularly relevant for international migration in this era of mass refugee movement and tightening borders, as migrants become stuck, sometimes for years, in “temporary” settlements. For example, the migration of an estimated 1.5-2 million Rwandan refugees to the DRC during the 1994 genocide led to massive deforestation for fuelwood use in and around Virunga National Park (3, 5). This deforestation increases risks of erosion, mudslides, and assault of women and children, who must travel further to gather wood (3, 4, 5).

The time is opportune to systemically integrate the environment into our understanding of international migration using innovative data science, collaborations, and training. Merging survey, cell phone, and social media data with high-resolution environmental data, as from satellite time series (e.g. 6), could bridge mismatches between scales of social and environmental data (7). Novel teams of social scientists, natural scientists, policymakers, and affected stakeholders could use findings to inform policy. Ultimately, infusing environmental science into training in migration studies is essential. Interdisciplinary centers can facilitate these collaborations and jumpstart training opportunities.

William Burnside1*, Heather Randell1, Noelle Beckman1, Jenny Zambrano1, Allison Howard2
1National Socio-Environmental Synthesis Center, 1 Park Place, Suite 300, Annapolis, MD 21401, USA.
2Department of Biology, University of Maryland, College Park, MD 20742, USA.
* Corresponding author: E-mail:
bburnside@sesync.org

REFERENCES
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2. Hunter, L. M., Luna, J. K., & Norton, R. M. (2015). Environmental dimensions of migration. Annual Review of Sociology, 41, 377-397.
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