Search-and-rescue operations in the central Mediterranean do not lead to more migrant crossings, a new study co-authored by Stefano Iacus, director of Data Science and Product Research at the Institute for Quantitative Social Science, revealed. The findings, which were published in Scientific Reports in August, challenged “pull effect” claims that state- and private-led search-and-rescue encourage migration.
“There were these ideas that search-and-rescue operations, both from the government and also from the NGOs, increased the willingness of migrants to reach the Italian coasts and enter Europe. There were pseudo-scientific claims saying that given the data, we can show that,” Iacus said.
Iacus, along with co-authors Alejandra Rodríguez Sánchez at the University of Potsdam, Julian Wucherpfennig at the Hertie School’s Centre for International Security, and Ramona Rischke at the German Centre for Integration and Migration Research used causal modeling to test whether those assertions were true.
The researchers first identified three distinct intervention periods between 2011 and 2020 that were based on key changes in the politics of search-and-rescue. These intervention periods correspond to the start of the Mare Nostrum operation in 2013, the beginning of a search-and-rescue operation led by Migrant Offshore Aid Station (MOAS) in 2014, and, finally, the extension of the Libyan search-and-rescue maritime area, as well as the increase in Libyan Coast Guard pushback.
Ultimately, their findings revealed the pull effect claims were unsubstantiated. The study showed changes in the number of crossing attempts via the central Mediterranean route could be recovered by plausibly exogenous factors. Researchers used other “push-and-pull factors” in their analysis and found that a similar number of crossing attempts could be expected during periods when private-led search-and-rescue was most active. Meanwhile, their prediction suggested a “substantially higher number of crossing attempts than what was actually observed during the period of involvement of Libyan Coast Guard in intercepting and returning boats to Libya after 2017, meaning that these other types of operations, and not search-and-rescue, have had an impact on migratory flows along this route.”
“Although it may seem counter intuitive at first to some — especially because search-and-rescue periods do coincide with a relatively low mortality rate and a higher number of arrivals, search-and-rescue operations do not affect an already existing flow, nor the stock of potential or prospective migrants willing to make the crossing,” the authors noted. “As hinted by previous research, search-and-rescue is a response to the higher flow, not the cause.”
Iacus said research topics and methods like his are helpful when it comes to evidence-based policymaking. “Science is helping policymakers do preliminary analysis to test policy that is in place, has been in place, or any modification of the policy,” he said. “All of these methods and research can help make better policies.”
The research described in this report was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation).
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