"We have found our experience with mold in the residence halls this semester extremely frustrating, as have other colleges and universities in rain-soaked areas this season," wrote Urgo.
The next day, Urgo wrote to say that 159 more students, who lived on upper floors where mold was less prevalent, would also be moved as a precaution. Late last week, the migration commenced.
An inspection of the remaining residence halls found "no indication of any systemic mold that would require shutting down any additional housing facilities."
St. Mary's brought in a Baltimore physician, Dr. Hung Cheung, to field health questions. Urgo said about 12 students had suffered symptoms related to mold and that one had gone to the hospital for an X-ray of his lungs, which came back clean.
The college said the mold came from the Penicillium and Aspergillus groups, listed by the Centers for Disease Control and Prevention as two of the four most common indoor varieties.
For people who are sensitive to mold, exposure can cause stuffy noses, eye and skin irritation, and wheezing, the CDC says.
Katie Dreyer, a student from Hereford who said the mold had made her sick, lauded the move to the Sea Voyager.
"It is far more of a disruption to be in hotels, disconnected from our community and fellow students for the entire semester," she wrote in an "open conversation" posted on the college's website. "I think moving to the boat is a great idea. I would live in a closet if it meant being able to live back on campus!"