What a dolphin’s death in Kerala reveals about India’s marine plastic pollution

At noon on July 4, 2026, locals found a humpback dolphin in the Indian Ocean (Sousa plumbea) and Indo-Pacific finless porpoise (Neophocaena phocaenoides) died at separate locations along the Kozhikode coast in Kerala. Following public notice, authorities collected the bodies for autopsy. The autopsy of the nearly 200kg dolphin, an endangered species on the IUCN Red List, revealed something alarming. It was observed that his stomach was empty and most of his organs were functioning normally, but the approximately 2 kg plastic fishing net tightly stuck in his esophagus disrupted normal nutrition and caused his death.

“He may have accidentally swallowed the net while feeding on sea prey, but he could not vomit it. We believe the net was initially in the stomach. As fermentation produces gas, the plastic formed into a ball under pressure and was forced into the esophagus,” says KM Manojlal, chief veterinary officer, Kozhikode District Veterinary Centre, who conducted the post-mortem.

The necropsy of the Indo-Pacific finless porpoise, which weighed around 80kg, suggested that it most likely died of drowning after an accident such as being entangled in a fishing net.

Human-induced stress in the marine ecosystem

Recent marine mammal deaths highlight the increasing impact of anthropogenic pressures on the marine ecosystem along India’s coastline, with plastic pollution, ‘ghost nets’ and fishing gear entanglement emerging as major threats, experts say.

Marine mammal strandings along the Indian coastline have remained relatively high in recent years. According to data from the Central Marine Fisheries Research Institute (CMFRI), Kochi, 171 strandings involving 14 species were recorded in 2024 and 161 in 2025. Among the states, Goa recorded the highest number of strandings in both years; 87 in 2024 and 113 in 2025, followed by Kerala (29 and 15 respectively). Tamil Nadu reported 14 strandings in 2024 and Maharashtra 11 in 2025.

Part of the plastic mesh was removed from the dolphin’s esophagus | Video Credit: special editing

Scientists say the threat is particularly high for coastal species such as the Indian Ocean humpback dolphin, which live in shallow waters less than 20 meters deep, often a few kilometers from shore, and come into direct contact with human activities. Although there are many reasons for the stranding, “anthropogenic activities” are considered the primary factor.

Indian Ocean humpback dolphins caused 129 strandings in a two-year period. Their numbers increased from 47 in 2024 to 82 in 2025. Goa accounted for the majority of groundings; There were 33 in 2024 and 68 in 2025. It was followed by Kerala (5 and 8 respectively) and Maharashtra (3 and 4).

The Indo-Pacific finless porpoise was the second most frequently stranded species, with 54 stranded in 2024 and 44 in 2025.

Percentage of Indian Ocean humpback dolphins out of total marine mammals stranded along India’s coastline in 2024 and 2025. Data shared by Central Marine Fisheries Research Institute (CMFRI), Kochi

For the last two years, CMFRI, through its extensive network, has been recording and assessing stranded marine mammals along the Indian coastline. But officials admit the actual numbers may be higher because many people go unnoticed.

Plastic pollution is among the biggest threats to marine biodiversity, says Ratheesh Kumar Raveendran, senior scientist at CMFRI’s Department of Marine Biodiversity and Environmental Management. “Millions of tonnes of plastic enter the oceans each year, where it persists for decades by breaking down into smaller pieces. Marine mammals often mistake plastic for food or accidentally ingest it while feeding, including when retrieving prey caught in fishing gear. Plastic ingestion can cause digestive blockages, internal injuries, starvation and chemical poisoning,” he says.

Mr Raveendran adds: “‘Ghost nets’ (abandoned, lost or discarded fishing gear) are another growing concern. Made from durable synthetic materials, they persist in the ocean for years and indiscriminately trap dolphins, whales, sea turtles, dugongs, sharks, rays and fish. Entanglement can cause serious injury, restrict movement and breathing, lead to drowning or lead to prolonged starvation and death.” may result,” he notes.

Divya Panicker, a visiting researcher at Woods Hole Oceanographic Institution (WHOI), argues that science-based, location-specific conservation measures are needed to protect coastal dolphins.

“Authorities should conduct autopsies and publish findings to help organizations and civil society direct conservation efforts. Such an approach will help protect species while supporting local livelihoods. The public can contribute by avoiding single-use plastics, especially soft plastics, and participating in beach clean-ups, benefitting dolphins and other marine life,” says Ms. Panicker.

Meanwhile, fishermen say that dolphins often tear fishing nets trying to gain access to caught fish.

Kerala Forest department officials said there was no comprehensive data on marine mammals stranded on the state’s coastline.

It was published – 10 July 2026 10:37 IST