Researchers predict sharp rise in migrants entering Europe covertly

An aerial view shows makeshift shelters and tents where migrants live in what is known as the ''Jungle'', along the Rocade road, an approach road to the French port of Calais, France, September 7, 2016. Picture taken September 7, 2016. REUTERS/Charles Platiau

In a report ahead of next week's U.N. Summit for Refugees and Migrants, the UK-based thinktank said 330,000 people are projected to arrive in Europe this year by sea, usually across the Mediterranean, compared with 1.1 million in 2015.

But ODI said this figure may create a false impression for European policy-makers that the migration crisis is over, as it fails to take account of other migrants entering covertly.

"While on the surface, the number of people arriving in Europe has fallen, the rate of those taking hidden routes to Europe has not been affected and is likely to increase," said Marta Foresti, author of the report in a statement.

"These covert routes can be more dangerous and make it harder for governments to monitor migration and design effective responses."

Since 2014 European countries have committed to spending 1.7 billion euros on tighter border controls, including a British plan to build a wall along the approach road to the French port of Calais to prevent migrants from jumping onto UK-bound trucks.

More than 15 billion euros has been spent on bilateral agreements, such as the EU-Turkey deal aimed at reducing the number of migrants traveling from Turkey to Europe.

"The public debate usually focuses on the costs of managing the flux of migrants who enter Europe," Foresti told the Thomson Reuters Foundation.

"The costs of containing and reducing migration are rarely in the spotlight."

Migrants using hidden routes are more likely to come from richer countries, mainly upper-middle-income countries, which the World Bank defines as the countries with a gross national income per capita of between US$4,036 and US$12,475.

While border controls and bilateral agreements may be effective in reducing flows along a specific route in the short term, in the long term they do not seem to deter people from traveling, Foresti said.

"They just take other routes," she said.

"Contrary to what we are seeing all over Europe, increasing legal routes is the only way to be able to predict flows and make pragmatic decisions about how to better manage migration."