Endangered dolphins are somehow surviving in one of the world's most polluted rivers
Researchers have counted around 20 Ganges river dolphins living in Bangladesh's Buriganga River, one of the most polluted waterways on Earth, raising questions about how the species is persisting there.
Researchers surveying Bangladesh's Buriganga River, ranked among the five most polluted rivers in the world, found roughly 20 Ganges river dolphins living along a 27-kilometer stretch, according to a year-long study conducted between September 2023 and August 2024. Nearly 16% of the dolphins sighted were calves, suggesting the population is still reproducing despite the pollution.
"The Buriganga is not a usual place for dolphins... we were amazed at how it was possible," said researcher Md. Aminur Rahman. The 29-kilometer river carries heavy metals including chromium, lead, cadmium, arsenic and mercury. Sightings peaked in December and through the winter months, with none recorded in October 2023 or July and August 2024.
Mohammad Abdul Aziz, a zoology professor at Jahangirnagar University, said protecting the dolphins will require addressing both water quality and fishing practices: "If we want to conserve the dolphins in the Buriganga, the priority must be to stop the pollution," he said, adding that illegal fishing nets also trap and kill the animals. A national survey conducted in 2024 and 2025 counted 2,307 Ganges river dolphins across 45 rivers spanning 4,900 kilometers in Bangladesh.
Based on reporting by Md Jahidul Islam for Mongabay. Read the original: https://news.mongabay.com/2026/09/against-the-odds-endangered-dolphins-survive-in-bangladeshs-polluted-river/
This article was produced with the assistance of AI tools and reviewed by an editor before publication.
