NOUADHIBOU: From the Mauritanian coast, Ahmed, a Senegalese man, looks toward Europe, the place he dreams of being but fears he will never reach due to heightened security against migrants in the west African country. “Everyone wants to leave,” said the 34-year-old, who keeps a low profile in Mauritania to evade constant police checks. But “since security was stepped up, no one can get through,” added Ahmed, whose name has been changed for security purposes.

As Mauritania tightens its borders and Europe hardens its migration policies, departures from the country's shores may be falling. But for many migrants gathered in Nouadhibou,…

NOUADHIBOU: From the Mauritanian coast, Ahmed, a Senegalese man, looks toward Europe, the place he dreams of being but fears he will never reach due to heightened security against…