Flavio Di Giacomo, spokesman for the IOM in Italy, pointed to the type of boats used to transport the migrants as one potential reason for the increase in deaths. In late May, for example, a boat without an engine capsized as it was being tugged by another vessel. More than 500 people were killed.
"It's the first time I've seen something like it," Di Giacomo said, adding that he is witnessing migrants being packed on to wooden boats that are unfit for navigation. Previously, the most common vessels used were rubber dinghies.
Younger and more unscrupulous smugglers have resorted to jamming increasing numbers of people into the extremely unsafe boats.
"There is competition between smugglers groups," he said. "There are young people who are trying to become smugglers and gain money that way."
Many migrants are making the journey on larger wooden vessels, which can hold more people.
Two shipwrecks on these bigger boats can result in as many as 800 deaths, Di Giacomo said.
About 2500 migrants - mostly travelling from Eritrea, Nigeria, Gambia and Somalia - already have died this year trying to cross the Mediterranean to Italy.
Speaking at a briefing in Geneva several weeks ago, William Spindler, a spokesman for the United Nations High Commissioner for Refugees, said refugees have a 1-in-23 chance of dying on the North Africa-Italy route.
The journey is longer and more treacherous than the eastern Mediterranean crossing, which takes migrants from Turkey to Greece.
Still, a few hundred migrants have died on the eastern route. The number of asylum-seekers on that route has plummeted following an agreement between Turkey and the European Union to bar refugees from making the trip.
So far, though, there is no sign that asylum-seekers are shifting to the central Mediterranean crossing.
Most of those travelling from Turkey to Greece are from Syria, Afghanistan and Iraq.
Dangerous journey
Here's a breakdown of what's happening in the Mediterranean:
• More than 200,000 refugees travelled by sea this year; about 7000 travelled by land
• About 150,000 arrived in Greece; about 50,000 arrived in Italy
• The top nationalities arriving in Italy are from Eritrea, Nigeria, Sudan, Somalia, Ivory Coast and Gambia. The top nationalities arriving in Greece are from Syria, Iraq, Afghanistan, Pakistan and Iran
• Last year, 475,000 Syrians and 205,000 Afghans travelled to Greece. Close to 75,000 Syrians and 40,000 Afghans have made the journey since May this year
• Last year, 12,000 Eritreans and 5000 Nigerians travelled to Italy; Close to 6000 Eritreans and 6000 Nigerians have made the journey since May this year
• Other than drowning, most other known causes of death in the Mediterranean include asphyxiation, boat fires, and exposure or hypothermia.