LONDON (NYTIMES) - The main route to Europe is experiencing one of its longest lulls since the migration crisis began in 2014.
Just more than 4,000 migrants have reached Italy from Libya since mid-July, about a fifth of the number during each of the equivalent periods of 2014, 2015 and 2016, according to the Italian Interior Ministry.
The lull provides rare respite for Italy, where migration - and the centre-left government's response to it - may prove to be a defining factor in a general election in the coming months.
After the European Union reached a deal with Turkey early in 2016 to try to stop migrants reaching the Greek islands in the Mediterranean, Italy once again became the main gateway to Europe - an unwanted title that it has held for most of the 21st century.
More than 600,000 people have reached Italy by boat since 2013, stretching national resources and bolstering support for nationalist groups in the country. Most of the migrants set off from the northern coast of Libya, where the absence of a single central government since the fall of former dictator Moammar Gadhafi has allowed human traffickers to work with impunity.
But that flow stalled suddenly and unexpectedly several weeks ago.
At the height of summer, when the weather is generally better, Libyan smugglers typically send waves of migrants to sea every week or so. But since July 15, there have been no such spikes.
"I'm still trying to explain it," said Mark Micallef, senior research fellow at the Global Initiative Against Transnational Organised Crime, a research organisation that documents human trafficking in Libya.
"If you look at arrival statistics historically, they should be hitting a peak now in July and August," he said.
"But instead we're seeing a dramatic drop."
The dip follows prolonged attempts by Italy to improve the capability of the Libyan coast guard and to discourage several nongovernmental organisations from operating migrant rescue boats off the Libyan coast.
Analysts cautioned that the lull was unlikely to be permanent because Libya's many competing militias and smugglers make so much money from the crossings that they will be unwilling to abandon the trade for long.