ON BOARD THE ASTRAL, OFF LAMPEDUSA, Sept 1 (Reuters) - A wooden dinghy carrying 19 African migrants is so heavily laden it is almost taking in water over its sides in the open sea off the Italian island of Lampedusa. The two babies onboard are crying. The dinghy, stuck in the Mediterranean with its outboard engine apparently broken, is just one of the boats helped by volunteers from the Spanish charity Proactiva Open Arms in the past days amid a surge in arrivals to Lampedusa. Migrant boat departures from Libya and Tunisia to Italy and other parts of Europe have increased in recent months due to the warmer weather. Around 11,000 migrants have disembarked on Italy"s coasts from the start of 2021 to May 7, up from 4,105 in the same period last year, interior ministry data shows. "The route from Tunisia to Lampedusa has suffered a huge increase (in crossings)... over the past year. A couple of days ago we had six rescues during one day, and on the same day over 800 people arrived in Lampedusa," said David Llado, Open Arms coordinator on the motorised sailboat Astral. The Astral is too small to take the migrants on board itself, but stays to provide support as night falls until they are picked up by the Italian coastguard. It keeps the dinghy in its searchlights after its team, on a speedboat launched from the Astral, give the migrants life jackets and water. Italian media said on Wednesday 191 migrants had been rescued overnight from seven different boats. According to the U.N.-affiliated International Organization for Migration, more than 1,100 people fleeing conflict and poverty in Africa and the Middle East have perished this year in the Mediterranean.