According to NBC News, the head of Thailand's Marine and Coastal Resources Department said the whale probably thought the floating plastic bags were pieces of food. For almost a week, veterinarians tried to nurse it back to health, but four days later, it died.
This image shows some of the plastic bags that were found in the stomach of the whale during an autopsy in Songkhla province, in southern Thailand. The whale also vomited five bags during the rescue attempt before it died, the department said.
After its death, 80 plastic bags were found lodged in its stomach, weighing around 8 kilograms.
Thailand remains one of the world's worst polluters, with government initiatives to convince people to use less plastic largely failing, they said.
Pilot whales mainly feed on squid, but are known to eat octopus and small fish when squid are not available, according to the American Cetacean Society, a whale conservation group.
"It's a huge problem", Thon Thamrongnawasawat, a marine biologist and lecturer at Kasetsart University, said.
The ABC notes that Thailand is one of the world's largest users of plastic bags and that its government is considering adding a levy on disposable plastic bags.
A pilot whale has died off southern Thailand after swallowing 80 plastic bags, Thai marine officials say. Of that, almost 270,000 tons of large and small plastic debris are on the surface.
A study published a year ago found that 83 percent of water samples from more than a dozen nations were contaminated with plastic fibers.
The dead whale is likely to have been the short-finned species of pilot whale, which have been nicked named the "cheetahs of the sea" due to their high-speed pursuits of squid. More than 60 pounds of trash clogged its digestive system. An autopsy found 17lb, or eight kg, of plastic in its stomach.