mumbai

Updated: Aug 27, 2017 23:54 IST

A day after devotees bid adieu to Ganesha idols on Saturday, decomposed carcasses of two marine mammals — an Indo-Pacific humpbacked dolphin and a finless porpoise — washed ashore at Carter Road promenade in Bandra and Aska Beach on Sunday morning.

According to officials from the state mangrove cell, the carcass of the Indo-Pacific humpbacked dolphin was eight-foot-long and the length of the porpoise was four-feet. While fishermen from Aksa informed the mangrove cell about the porpoise around 9am on Sunday, Bandra residents informed the officials about the dolphin carcass around 2pm though it was first seen around 10am.

Mangrove cell officials said the dolphin carcass had washed ashore at Juhu Beach on Friday but was pulled back into the sea during a high tide. “We could not conduct a post-mortem of either of the mammals as their bodies were mutilated and were inflated owing to formation of methane gas. Also, their internal organs had come out,” said Prashant Deshmukh, range forest officer, state mangrove cell. “We cannot say what might have caused the deaths, but they must have died in the deep sea last week.”

He added that while the porpoise was buried at Aksa beach, the dolphin was buried at a mangrove patch near Versova beach.

The state has invested Rs1 crore to build marine mammal rescue centres in every district along Maharashtra’s 720km coastline. The state mangrove cell will construct the city’s first marine mammal rescue centre at Juhu beach by December.

Porpoises have smaller mouths and spade-shaped teeth as opposed to dolphins that have prominent, elongated beaks and cone-shaped teeth. Also, a dolphin has a curved dorsal fin while a porpoise has a triangular dorsal fin.

Whales, dolphins and porpoises are endangered species and are protected under Schedule I of the Wildlife Protection Act, 1972.

What’s causing marine animal deaths?

While there is no conclusive proof for almost 80 marine animal deaths over the past two years, there have been several speculations. HT takes a look at some of them:

- Pollution close to coastlines leading to extremely poor water quality

- Plastic trash at sea choking these species

- Injuries after being hit by large vessels at deep seas

- Climate change and sea level rise

- Lunar tides – marine animal beaching taking place during full moon and new moon nights after the tides recede

- Fishermen alleged that oil companies carrying out seismic surveys - seismic blasts from ships to the ocean floor to identify oil and natural gas – that disorient the communication pattern for marine mammals leading to accidents

- Marine animals getting caught at large nets close to the shore and deep sea

- Oil spills at dockyards and at deep seas choking marine animals

- Rise in sea surface temperatures pushing mammals closer to the surface of the ocean and then getting hit by large vessels