IN THE SPIRIT OF THE CAJUN NAVY: Spared Irma’s Worst, Puerto Ricans Sail to Virgin Islanders’ Aid.

Puerto Ricans relieved at being spared the worst destruction donated water, clothing, first aid and other supplies, and dozens of recreational boaters sailed to nearby islands to deliver the assistance and evacuate now-homeless islanders on the return trip.

A 54-foot dive boat named the Tobias cast off on Sunday morning from the marina here, the largest in the Caribbean, and made its way eastward under a searing sun to St. Thomas in the Virgin Islands, the fourth vessel of the day to make the trip. It would return later crowded to capacity with 46 St. Thomas residents escaping the near-total devastation of the island.

“We were very blessed here, and we have to do everything we can to help,” said Cristina Morales, the owner of the Tobias. . . .

The civilian sealift, by contrast, has been largely a spontaneous, volunteer affair. And it has grown out of the longtime affinities and links among recreational boaters in Puerto Rico and the islands to the east.

Puerto Ricans often cruise to the American or British Virgin Islands, known interchangeably here as “las islas,” to enjoy their crystalline beaches or for fishing competitions. One week-long event held in July in the British islands attracts such a large contingent of visiting boats that locals joke about hosting the Puerto Rican Navy.

“We’ve enjoyed the beauty and the fun of those islands,” said Martita Rivera, who has vacationed in the islands for 25 years. “We only saw the need to say, ‘We’re here for you.’ ”

Ms. Rivera and her husband, Roger Casellas, run one of the pop-up donation centers from Mr. Casella’s boat dealership in Hato Rey. They have received everything from diapers and shirts to nails and hammers.

Responding to a call to arms on social media, she said, hundreds of volunteers have helped to pack four shipping containers full of supplies that will be delvered to the islands this week.

Bravo.