120 dolphins found dead in Brazil's Amazon river as water temperature nears 40 degrees. Video

Amazon river dolphins, many bear a striking pink colour, are a freshwater species found only in the rivers of South America. (Image credit: Reuters)

The carcasses of more than 120 river dolphins have been found floating in a tributary of the Amazon river in Brazil over the last week in circumstances that experts suspect were caused by severe drought and heat as water temperatures soar close to 40 degrees Celsius.

The dead dolphins were all found in Lake Tefé over the week, according to the Mamirauá Institute, a research facility funded by the Brazilian Ministry of Science.

Amazon river dolphins, many bear a striking pink colour, are a freshwater species found only in the rivers of South America. They are one of a handful of freshwater dolphin species left in the world.

Drought and high temperatures kill dolphins in Brazilian Amazon rainforest pic.twitter.com/e2UneIbA1c

— Citizen YC (@CitiznYC) October 4, 2023

Apart from the dolphins, thousands of fish have also died, the local media reported. “We have documented 120 carcasses (of dolphins) in the last week,” said Miriam Marmontel, a researcher at the institute told Al Jazeera.

The incident is likely to add to the concerns of climate scientists over the effects of human activity and extreme droughts on the region.

“It’s still early to determine the cause of this extreme event but according to our experts, it is certainly connected to the drought period and high temperatures in Lake Tefé, in which some points exceeding 39 degrees Celsius (102 degrees Fahrenheit),” the institute told CNN Brasil.

The Amazon River, the world’s largest waterway, is currently in the dry season, and several specimens of river fauna are also suffering from record-high temperatures.

Deaths of 120 Amazon dolphins linked to severe drought, high temperatures. Amazon River’s pink, grey dolphins are a threatened species and among the few freshwater dolphins found in the world. A dead #Amazon dolphin at #Solimoes River in Tefe, #Amazonas state, Brazil 09/1/2023. pic.twitter.com/IxgPJWYAXH

— Taj Pharma - Asia, Africa, North America & Oceania (@TAJPHARMA181638) October 3, 2023

Researchers, activists, and volunteers are now trying to rescue surviving dolphins by transferring them to the main body of the river where the water is cooler, but the operation is not easy because of the remoteness of the area, CNN Brasil reported.

“Transferring river dolphins to other rivers is not that safe because it’s important to verify if toxins or viruses are present (before releasing the animals into the wild),” André Coelho, a researcher at the Mamiraua Institute, told the broadcaster.

Meanwhile, authorities said that even more acute droughts are expected over the next couple of weeks, which could result in more dolphin deaths, CNN Brasil reported.

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