Authorities in Hawaii are referring 33 people to federal law enforcement after the group allegedly swam around and harassed a pod of wild dolphins.
The incident took place in the waters surrounding Hawaii's Big Island.
Federal law prohibits swimmers from coming within 50 yards (45 meters) of spinner dolphins along the Hawaiian shoreline waters. Federal officials enacted the rule in 2021 over concerns that so many tourists were trying to swim with the animals that it was disrupting their sleep cycles.
The rule is in effect for waters within two nautical miles (3.7km) of the Hawaiian Islands in and specific waters around the islands of Lanai, Maui, and Kahoolawe, according to the Associated Press.
Law enforcement officers spotted the group of 33 swimmers on Sunday during a patrol, according to the state's Department of Land and Natural Resources.
Drones captured aerial images of the swimmers following the group of dolphins while the animals attempt to swim away. The department characterised the swimmers as individuals "who appear to be aggressively pursuing, corralling, and harassing the pod."
Department officers interdicted the group and told them they were in violation of federal law. Police and department officials met with the swimmers back on land where federal and state officials began a joint investigation.
Spinner dolphins are nocturnal creatures, and need their sleep during the day to ensure they have the energy to seek out food at night. The animals typically eat fish and small crustaceans that swim along the water's surface at night. The dolphins sleep in shallow bays during the day to protect themselves from larger predators, but this also puts them within the reach of curious humans.
The incident sparked sharp condemnation for the swimmers on social media.
One user simply wrote that "people are disappointing," while another called for law enforcement to "prosecute to the fullest extent of the law."
"Don't just slap [these] disgusting people on the hands," the Twitter user wrote.
Another user noted it would likely be difficult for a swimmer to tell their exact distance from a dolphin while both are swimming.
"Unclear how a swimmer could know a dolphin is within 50 yards, I can't tell if I'm 50 yards from the shore," they wrote.
Swimmers who inadvertently approach or are approached by the dolphins are instructed to make efforts to swim away from the dolphin and are prohibited from trying to enagage with the creature.
Dolphins don’t appear to be sleeping in the way we understand sleep as humans, which can lead to confusion for swimmers. Dolphins still have to keep moving and surface air, even while they’re technically asleep. The movement can lead swimmers to believe the dolphins are awake and active when they actually are at rest.