The local migrants housing center had been empty until Sunday, but rapidly surpassed its 200-plus capacity.
Dozens spent the night just outside the center, carefully watched by Italian state police and military personnel, after spending hours on the dock.
The mayor said the 800 ready to leave have already been tested for COVID-19, but they will spend 10 days on the ferry.
The latest arrivals on Lampedusa, a 20-square-kilometer (about 8-square mile) island closer to northern Africa than to the Italian mainland, was the biggest number of migrants to come ashore in a single day at an Italian port this year.
This year’s arrivals have already topped by far the number of migrants arriving via sea in the same period in each of the past two years.
According to Interior Ministry figures, by May 10, 2019, just over 1,000 people had arrived by sea; by the same date in 2020, 4,184 had arrived, and this year so far nearly 13,000 have arrived.
The numbers, though, are far lower than those earlier in the past decade, when hundreds of thousands of rescued migrants were brought to Italy within the span of a few years.
The mayor of Lampedusa renewed urgent appeals to the Italian government to deal with the sea migrant issue.
Lampedusa lives off tourism, and Italy has just launched a national campaign to quickly vaccinate residents of tiny islands against COVID-19 ahead of the looming holiday season.