September 12 is World Dolphin Day.

Marine conservation and advocacy nonprofit Sea Shephard created the day in 2022 to remember that dolphins, among the most intelligent animals on Earth, are under threat and need protection.

That date, Sept. 12, was chosen to memorialize the massacre of 1,428 Atlantic white-sided dolphins (Leucopleurus acutus) on the Faroe Islands, an archipelago of Denmark, in 2021.

Mongabay has reported widely on dolphins this year, including how they’re recovering from an oil spill in the Gulf of Mexico, and a “love potion” myth threatening the Peruvian Amazon’s pink river dolphins.

Dolphins still sick from 15-year-old oil spill

Bottlenose dolphins (Tursiops truncatus) in Barataria Bay in the U.S. state of Louisiana are still showing signs of severe illness years after the 2010 BP Deepwater Horizon disaster, Mongabay’s Liz Kimbrough reported in April.

The largest marine oil spill in history left 134 million gallons, or more than half a billion liters, of crude oil in the waters of the Gulf of Mexico. Dolphins exposed to the oil showed higher mortality rates, increased prevalence of moderate to severe lung disease, impaired stress responses, high rates of reproductive failure, and overall poor health.

One individual, Y21, examined in 2011 while pregnant, had three miscarriages before dying in 2019. “She was extremely ill,” Cynthia Smith, a researcher at the National Marine Mammal Foundation, told Kimbrough. “You could just tell by the way her eyes looked, the way she was breathing. She was somewhat dull, a little bit too quiet.”

Younger dolphins, born after the spill, were found to be in better health. “We are optimistic that the next generation of dolphins can lead the population to recovery,” Smith added.

Pink river dolphins and the myth of pusangas

In Peru’s Amazonian port city of Iquitos, the endangered pink Amazon river dolphin (Inia geoffrensis) face another kind of threat. A Mongabay documentary published by video producer Romi Castagnino in February, exposed how myths surrounding pusangas, or love potions made from dolphin oil and body parts, fuel an illegal trade.

Vendors selling the potions in street markets and on the internet claim pusangas contain the dolphins’ natural pheromones and have seductive powers on humans. “Pour four drops … and she’ll be madly in love with you,” one seller says.

Fewer than 10,000 pink Amazon river dolphins remain in the wild today. Along with destructive fishing practices that cause dolphin bycatch and habitat loss, the potions pile pressure onto an already threatened species.

The pusanga practice is opposed by several riverine and Indigenous communities. Kukama healer Lander Pizango told Mongabay that pink river dolphins are deeply respected. Asked about love perfumes, he said: “I don’t engage in that … You would have to kill dolphins.”

Banner image: A sick adult female dolphin, Y21, during her health assessment in Barataria Bay, Louisiana. Image courtesy of Todd Speakman/National Marine Mammal Foundation.