A Man Fell From a Cruise Ship. And Survived.

The Carnival Valor had been at sea for only a day when calls came over the loudspeaker asking a certain passenger to please report to customer service.

The man, a 28-year-old American citizen, had been reported missing by his family that morning.

It was Thanksgiving, and the Valor, a 3,756-passenger cruise ship that had left New Orleans the day before, was heading toward Cozumel, Mexico.

Crew members soon began searching passengers’ cabins, said Shant’a Miller White, who was traveling with her husband and family. One employee entered her cousin’s cabin and said, “We just need to make sure everything is OK.”

“We didn’t know what was going on,” Ms. White, 48, recalled. Then, at dinner, came another announcement: The ship needed to change course to execute a search and rescue operation.

Ms. White pictured the unknown passenger alone in the water and felt sick to her stomach.

“Did they fall to the bottom? Did the sharks get them?” Ms. White recalled thinking. She began to pray.

The passenger, according to the Coast Guard, turned out to be James Grimes, 28, who had been traveling with his parents and siblings on the five-day cruise. His family had last seen him the night before, around 11 p.m.

But by 10:45 on Thanksgiving morning, when there was no sign of him, the family notified the crew, the Coast Guard said.

At 8:10 p.m., more than nine hours after his family reported him missing, a passing tanker spotted the man near the mouth of the Mississippi River and alerted the Coast Guard.

Rescuers found Mr. Grimes struggling in the water, waving frantically and trying to keep his head above the surface.

When the crew of the MH-60 Jayhawk helicopter lifted him out, he was in shock, had mild hypothermia and was extremely dehydrated, said Lt. Seth Gross, who managed the search and rescue operation for the Coast Guard. But he was alive and in stable condition.

Mr. Grimes, whose family described him as an exceptional swimmer, had treaded in 65- to 70-degree water for hours, withstanding rain, 20-knot winds and three- to five-foot waves in the Gulf of Mexico, where bull sharks and blacktip sharks are common, Coast Guard officials said.

“This case is certainly extraordinary,” Lieutenant Gross said. “The survival instinct, the will to survive is just crazy.”

How often does this happen?

Falling from a ship into a vast sea may be a cruise passenger’s worst nightmare. While the chances of going overboard are exceedingly remote, according to statistics from the Cruise Lines International Association (CLIA), the outcome is usually tragic.

In 2019, 25 people fell overboard, and only nine of them were rescued, according to CLIA.

In February, a woman aboard the Carnival Valor jumped off the 10th deck of the ship while fleeing security officers who were trying to detain her after she had scuffled with them. Her body was never found.

In December 2016, a 22-year-old man fell off the 12th deck of a Royal Caribbean cruise ship after a night of heavy drinking. His parents sued the cruise line in federal court in Florida, but a jury decided in favor of Royal Caribbean.

Alcohol is a factor in at least 11 percent of falls from cruise ships, which often offer all-inclusive drink packages that encourage drinking onboard, said Ross Klein, a professor of social work at Memorial University of Newfoundland, who researches cruise safety.

“Cruises are viewed as idyllic, safe and secure, and of course those views are reinforced by advertising and public statements,” he said. But the public should be aware of the risks of going on a cruise, which include being pushed overboard, going overboard and being tempted to jump overboard, he said.

How do ships prevent people from going overboard?

By law, railings have to be 42 inches tall, Professor Klein said. There were efforts to make the railings taller by about another foot, he said, after Congress began considering legislation to tighten security on ships in 2005. But in 2010, when Congress passed the Cruise Vessel Security and Safety Act, the railing height requirements were set at the current standard, he said.

The railing height is designed to keep passengers along ship promenades, said Brian Salerno, the senior vice president for Maritime policy at CLIA.

“The vast majority of cases are either reckless behavior or some form of intentional act,” Mr. Salerno said. “People don’t just inadvertently fall over the side of a ship.”

Professor Klein said cruise ships could limit the risks of passengers falling overboard if they limited alcohol consumption, increased railing heights and installed technology that senses when a heavy object has fallen from the ship.

The 2010 law directed cruise ships to begin developing and installing such technology, Mr. Salerno said.

It took years to create a video-surveillance system that would be sensitive enough to detect a person falling overboard and alarm a ship’s crew but that wouldn’t be triggered by other objects, like a sea gull flying by, he said. Some ships have already begun installing such systems, Mr. Salerno said.

Bartenders on cruises are also trained to watch for excessive drinking, said Robert Kritzman, a partner at Clyde & Co., an international law firm in Miami, who advises cruise companies.

“The general policy is the same as anywhere else: Once somebody becomes excessively intoxicated, you stop serving,” he said.

Carnival Corp. said the “only way to go overboard is to purposefully climb up and over the safety barriers.”

“Cruise ships have safety barriers in all public areas that are regulated by U.S. Coast Guard standards that prevent a guest from falling off,” the company said in a statement that thanked the Coast Guard and the mariner who found Mr. Grimes. “Guests should never ever climb up on the rails.”

A spokesman did not respond to follow up questions about the incident or Carnival’s safety protocols.

What happens when the crew learns that a person has gone overboard?

Cruise ships have clear protocols for what to do when a person goes overboard, Mr. Kritzman said.

Once the crew members learn that a person has gone overboard, they immediately inform the Coast Guard, stop the ship and turn around to help find the missing passenger. Often, smaller, fast boats are deployed from the ship to search for the person, Mr. Kritzman said.

The circumstances around the recent fall from the Carnival Valor, including the precise time that Mr. Grimes went overboard, remain unknown. The Coast Guard said it was investigating the incident.

Lieutenant Gross said that after the Coast Guard learned about the missing passenger, it launched a 45-foot patrol boat, a helicopter and a tracker plane to search for him. The Coast Guard set up a search area of more than 7,000 square nautical miles, roughly the size of Massachusetts, he said, and immediately alerted any mariners around the Gulf of Mexico to look for the man.

The Crinis, a bulk carrier, spotted Mr. Grimes about 20 miles south of Southwest Pass, a channel at the mouth of the Mississippi River.

Lt. Gross said he called the man’s mother and stepfather to tell them he had been found.

When he told them their son was stable and being treated at a hospital in New Orleans, he heard them cheer and cry.

Ms. White, who lives in Hampton, Va., and runs an anti-bullying organization, said she was flooded with relief when the ship announced that Mr. Grimes had been found alive.

“That was nothing but God that he survived,” she said.

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