Mr Santoso said the mammal was male and the 13 pounds of trash in its stomach were identified as 115 plastic cups, four plastic bottles, 25 plastic bags, two flip-flops, a nylon sack and more than 1,000 other plastic pieces.
A picture from WWF of the stomach's content showed that the whale had even swallowed what looked like a piece of a melamine dining plate.
"Although we have not been able to deduce the cause of death, the facts that we see are truly terrible", Dwi Suprapti, a marine species conservation coordinator at WWF Indonesia told the AP.
Trites said similar whale deaths have been observed in Spain and Germany, and while B.C.has far cleaner waters than Indonesia, "it is just a matter of time before one of our sperm whales washes ashore with a stomach full of plastic".
A dead sperm whale that washed ashore, in Wakatobi National Park in Sulawesi province.
Almost half of the three million tons of mismanaged plastic waste produced in the country each year ends up in the ocean.
The cause of the death was still unknown and the carcass was to be buried on Tuesday without a necropsy because of its decayed condition.
A dead whale washed ashore in Indonesia with 115 plastic cups and two flip-flops inside its stomach
Wakatobi district, a picturesque collection of four main islands surrounded by a marine reserve, has urged Indonesia's central government to help tackle the problem of marine debris. The country creates more than three million tonnes of mismanaged plastic waste every year.
It's not known exactly how the whale died.
Last year, the Indonesian government announced it will pledge $1 billion a year toward reducing marine waste by 70 percent by 2025.
Researchers found 6 kg of plastic in the animal's stomach.
Indonesia's coordinating minister for maritime affairs, Luhut Binsar Panddjaitan, said more needed to be done to create awareness about the impact of plastic waste in our oceans.
Pandjaitan has pushed the government to take tougher action on plastic to help protect our oceans.
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