Stinky the dolphin is lonely, and he's getting way too frisky with humans.

The lone male bottlenose dolphin has been cavorting for months in waters off the Cayman Islands, a rare case of a solo dolphin far from a pod of his fellows.

The sight of the dolphin has delighted many boaters, swimmers and divers, but his antics dismay scientists who traveled to the archipelago to study him. They say Stinky is a danger to humans, and they also worry the dolphin could hurt himself.

"He spent a fair amount of time engaging in very high-risk behavior," said Laura Engleby, a marine mammal branch chief with the U.S. National Oceanic and Atmospheric Administration. "There is concern for his safety."

She noted the dolphin has a fondness for boat propellers in motion, and that he also likes to rub against anchors, channel markers and mooring buoys, cutting himself in the process.

Scientists estimate he is roughly 20 years old given his worn-down teeth and aging scars.

"He's certainly been around the block," said Trevor Spradlin, a marine mammal biologist with NOAA who also traveled to the Cayman Islands.

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It is unusual for bottlenose dolphins to separate from their pods, with only about 30 such cases reported worldwide, scientists said. Also puzzling is how Stinky arrived in the Cayman Islands, given that the nearest pods of bottlenose dolphins are in Cuba and the Bahamas, said Dr. Chris Dold, vice president of veterinary services for SeaWorld Parks and Entertainment, who also studied the dolphin.

Dold said the absence of female dolphins might help explain Stinky's behavior.

"What's unusual about this, of course, is not necessarily the behavior that this male dolphin is demonstrating, but that those behaviors appear to be directed toward people," he said.

Cayman Islands videographer Michael Maes can attest to that.

He was scuba diving with his wife and a friend near Grand Cayman when he spotted Stinky. He tried to catch his wife's attention to no avail.

"I turned my head away from her and Stinky was there, maybe 15 inches (38 centimeters) away from me," Maes said. "His eyes (went) straight into my eyes, so I went crazy, like, 'Hello! There's a dolphin.'"

He began to film until his wife urged him to surface and leave Stinky alone.

"My wife, he tried to eliminate her," Maes said. "He charged her like five times, but forcefully."

The dolphin then tried to mate with Maes, who at one point put his back against a coral wall as he does when sharks approach.

"But a dolphin, he just joins you," Maes recalled with a laugh.

The incident was caught on a sometimes frightening video that has been viewed nearly half a million times on YouTube.

Maes said he posted the video to warn people to leave Stinky alone. This is not a "swim with the dolphins" sort of animal. He said a few days after his encounter, a woman tried to ride Stinky's dorsal fin, only to get bitten.

"People just don't get the message," he said. "Leave those dolphins alone."

The Cayman Islands' Department of Environment has said it will launch an education campaign to highlight that message.

The NOAA biologists urged people to get out of the water if they spot Stinky because they could get injured. The dolphin has demonstrated aggressive behavior such as opening his mouth wide, which some people misinterpret as a welcoming smile that is quite the contrary, Spradlin said.

"He has done jaw pops, tail slapping, chuffing, pushing, charging," he said. "People need to understand these warning signs."

Spradlin said that integrating Stinky into a pod of dolphins elsewhere in the region is not realistic because scientists do not know enough about him. There are two types of bottlenose dolphins: those who live near coastal areas and those who live in deep water. It is unclear to which group Stinky once belonged.

"He's left by himself," Spradlin said. "He's been socializing obviously with people and with vessels."

Local government officials also considered placing Stinky in captivity, especially since the island already has two dolphinariums.

But Engleby rejected that idea, saying it's best to keep the dolphin in its natural environment.

"A public display would be an option of absolute last resort," she said. "This situation can be managed as long as people manage their behavior."