The bodies of 7 spinner dolphins were washed ashore at fishing hamlets in Tamil Nadu’s coasts on Tuesday. On Monday, 5 spinner dolphins were found dead in the same area.

In total, about 14 dolphins have been found dead in the last 3 days, according to a Deccan Chronicle report. Three dolphins were found at Venapurusham Kuppam in Mamallapuram and Sadras Kuppam, Uyyali Kuppam, Nainar Kuppam and Cuddalore Chinna Kuppam each saw one body washing ashore, according to the report.

Marine mammal specialist Supraja Dharini told DC that the dolphins could have all drowned after being trapped in Purse Seine fishing nets, found on steel boats used by fishermen in Cuddalore. Spinner dolphins need to resurface every 15-20 minutes to breathe.

TA Pugalarasan, Sea Turtle Protection Force (STPF) Member, in a report in The Hindu, said that all the dolphins must have been trapped in the same net and died due to suffocation.

He also speculated that a few spinner dolphins could have escaped in a semi-conscious state, but could have then been carried away by strong ocean currents and would have eventually died.

Apart from the dolphins, the STPF also found two dead green turtles washed ashore in Cuddalore Chinna Kuppam.

The dolphins reportedly had all the characteristic features of spinners, including long and thin beak, dorsal fins which are triangular towards the end, dark stripes from eyes to flippers, dark lips and pointy beak tips.

Stranded dolphins and whales on the coasts are not an unusual sight as the months from November to April is the migratory season. However, never before have dead dolphins been washed ashore in such large numbers.

“This is why we are convinced that the dolphins may have been trapped in a large net,” said Supraja to The Hindu