PARIS (AP) -- Nearly nine times more migrants have died so far this year in Mediterranean crossings compared to last year at this time -- swallowed by the sea as Europe beckons.
Why is this the year of so many deaths? There is no single reason. A chain of factors interlock, overlap and unfold into catastrophe on the high seas.
Smugglers are bolder and increasingly ruthless. They're taking more risks with unseaworthy vessels, and sometimes sending migrants out with no one at the helm.
The phasing out last fall of Italy's Mare Nostrum rescue operation, which used big ships to comb the sea far and wide, has left a gaping void that is filled in part by hulking merchant ships ill-equipped to pluck panicked souls from small, capsizing vessels.
The International Organization for Migration, or IOM, estimates that as of May 7 Mediterranean deaths stood at 1,829, compared to 207 in the same period in 2014. This year's rate soared before the onset of the warm season when crossings multiply, and despite a boom in successful crossings last year.
More people are risking the journey this year -- with about 39,500 arrivals by late April this year compared with 32,500 over the same period last year, when arrivals soared, according to the U.N. refugee agency. Their mortality rate en route is higher, too: Roughly 1 in 22 have died so far in 2015 compared to 1 in 157 in the same period last year.
Deaths can only be estimated. Real numbers may be higher, because some migrant vessels may simply disappear at sea.
The transit from Libya to Italy is by far the deadliest. Just 290 kilometers (180 miles) separates the smuggling haven of Libya from Lampedusa, the southern Italian island where tens of thousands of migrants land. The crossing to Italy accounted for an estimated 1,780 of the 1,829 Mediterranean deaths recorded so far this year by the IOM. Even subtracting two major shipwrecks that killed at least 1,200, the number of migrants swallowed up during the trip toward Italy has soared.
What experts call the "push" factor remains as strong as ever -- the reason people leave their home countries for the treacherous journey to Europe. Syrians escaping civil war and Eritreans fleeing a hard-line regime that requires indefinite army service accounted for the largest number of arrivals in Italy last year.
And most often Syrians and sub-Saharan Africans transit through Libya -- a country in chaos, without a central government, that has become a thriving center for smugglers.
Flush with desperate migrants seeking a sea crossing, smugglers are more numerous, more reckless, and able to operate with impunity in lawless Libya, experts say.
"When there is demand, there is supply. There is a lot of money in it," said Martin Xuereb, director of the non-profit Migrant Offshore Aid Station, or MOAS, which is based in Malta, an arrival point for migrants. "The more money you rake in," he said, "the more reckless you become."
As examples experts cite: increasingly unseaworthy vessels, including wooden fishing boats or inflatable rubber dinghies; vessels dangerously overloaded with migrants; more crossings and in dubious weather conditions.
Wood is rotting on the old, badly refurbished fishing boats, likely made in Egypt or Tunisia and bought for a song, said Flavio Di Giacomo, spokesman in Italy for the International Organization for Migration. He called the rubber dinghies as something to be used "if you go to the beach" that "takes seconds to sink."
That such vessels are overloaded with migrants ensures that many of them are doomed.
"Every boat that leaves has a very high possibility of shipwreck," Di Giacomo said.
In the past, migrant vessels could travel two to three days. Distress calls now go out soon after they leave Libyan shores.
Multiple calls for help can come within hours, something new this year, Di Giacomo said. Response capacities of the Italian coast guard and other rescue vessels, small and normally working close to the Italian coast, are stretched. Merchant vessels are transformed into rescuers instead.
Merchant ships "uphold the age-old tradition of rescue at sea," said Xuereb of MOAS, but "this is not their mission." Such rescues carry their own dangers, he and others note. Crews are not trained for rescue operations and giant vessels, often towering tankers or container ships, are not equipped.
But they render a precious service. Commercial vessels saved 41,000 migrants last year, according to IOM. It was not known how many migrants drowned in those rescues.
Weather is no longer a smuggler's guide. Numerous boats were leaving in numbers in January and February "when the weather can change within a matter of hours," said Xuereb.
Migrants in dinghies are sent off with a GPS and a satellite phone. And for the first time, "ghost ships" without navigators and set on autopilot have been used for Mediterranean crossings, notably an old cattle freighter launched New Year's Eve packed with migrants in pens.
Deteriorating conditions in Libya may fuel the cynical tactics. "Whether you repair washing machines or you smuggle migrants, your day has gotten a lot tougher," said Joel Millman, a Geneva-based spokesman for the IOM. "They are acting with more reckless abandon. They have found a model that works."
WITHOUT MARE NOSTRUM
The Italian search-and-rescue operation that began in October 2013 and was phased out starting last October saved more than 140,000 lives. But Italy said it alone could not foot the 9 million euros ($10 million) monthly bill.
Mare Nostrum ships, operating in international waters, patrolled close to the Libyan coastline. The European Triton operation replacing it has a reach of just 30 miles (50 kilometers) off the Italian coast, at least 150 miles from the Libyan shore -- at a third of the price. Yet the majority of vessels in need are close to the Libyan coast.
There is general agreement among experts that the end of the Mare Nostrum mission clearly contributed to the increase of deaths.
Many fear stepped-up migrant death rates will continue an upward spiral in the warm months ahead. European countries like France, Germany, Britain and most recently Ireland are contributing to the current Italian effort.
Humanitarian groups like MOAS, which began working this year with Doctors Without Borders, are stepping in to fill the void. MOAS' specially outfitted Phoenix boat, one of two, combs international waters near Libya where Mare Nostrum once patrolled.
The EU is now proposing to capture and destroy smugglers' boats.
However, Kris Pollet, a senior policy officer at the Brussels-based European Council on Refugees and Exiles, said smugglers are flexible.
"The modus operandi of smugglers changes all the time, and even their smuggling routes can change depending on the policy of states," he said. Smugglers find new ways to organize the sea voyages, "and it's not always the safest."