A 42-feet long, 15-feet wide Bryde's whale (Balaenoptera brydei), weighing around 40,000 kilograms or 44 ton washed ashore in Mandarmani, a coastal resort village in the eastern Indian state of West Bengal, with the ebbing waters on the night of July 27. The next morning, people on the coast were intrigued and excited at the same time. Locals in Mandarmani had heard stories of sharks, rays and whales. This was the first time they saw one.
By breakfast, people from nearby coastal villages had poured in. They touched the dead mammal to feel its slimy skin, peeped into its blowhole and took selfies. By forenoon, tides swept the carcass into the water only to bring it back again, this time closer to the delta mouth.
When teams of forest departments, conservationists, and scientists reached the area,“everyone who lived in and around Mandarmani was circling the giant whale,” Dr Srinivasan Balakrishnan, scientist at the Marine Aquarium & Regional Centre, Zoological Survey of India , who identified the species, told VICE News.
As the forest officials and local volunteers tackled the crowd, cordoned off the area, and took care of the logistics – ladders and buckets, slings and weightlifters, antiseptics, masks, and gloves--Dr Balakrishnan and his associate investigated the stranded mammal to ascertain the reason of its death and stranding, and decided the next steps. “We did a preliminary investigation but a thorough necropsy couldn’t be done due to the COVID-19 situation. We sent the tissue samples for DNA and molecular study and are awaiting results,” said Dr Balakrishnan.
In India, giant whales are protected under the Wildlife (Protection) Act, 1972. Scientists and research organisations require permission from the forest department to proceed with research activities. This means intricate paperwork, and Dr Balakrishnan confirmed that he’s interested in preserving the stranded mammal for studies.
Stranding and Beaching of Marine Mammals
“When marine mammals wash into the coast and find it difficult to return, we call it stranding or beaching,” Dr Balakrishnan said. Recently, three humpback whales lost their way and swum 18 miles inland into Australia's East Alligator River. Since January last year, an unusually high number of gray whales have been stranding along the west coast of North America. So far, there have been 194 cases in the US alone and 378 cases in the US, Mexico and Canada combined.
Scientists at the Central Marine Fisheries Research Institute, India, have tried to explain the mass stranding of 81 short-finned pilot whales in Manapad, a coastal village in the southern Indian state of Tamil Nadu, in 2016. Around four decades ago, 147 whales of the same species were stranded at the same location.
Reasons behind stranding
“Sadly, we cannot still say why a large whale has died and washed ashore,” Dr Dipani Sutaria, Marine Ecologist, James Cook University, told VICE News. “Mostly, there is no external injury. In such cases, it’s hard to say if it's human-induced mortality or disease or old age or a calf separated from its mother/pod or lack of food.”
While locals want to take a glimpse of the species, scientists and conservationists have their own tasks cut out. “It’s not possible at all to save a baleen whale from dying if it has beached. In fact, it’s not possible to save even mid-sized cetaceans. They most likely will get washed back to shore, but it can be tried. Usually, rehab and refloat succeeds only for small-sized dolphins (up to 13 feet in length),” said Dr Sutaria, a pioneer in establishing local and regional stranding networks across coastal India.
“For a live mid and small-sized cetacean that strands, the first and foremost action should be to ensure its comfort,” said Dr Sutaria. So when a live cetacean floats in and gets stuck at the shore, conservationists, researchers and volunteers across stranding networks in coastal India strive to keep the crowds away, gently remove sand from under the body, and fill the pits up with water. They then cover the animal (not the blowhole) with wet towels so that the animal stays wet and feels as light as possible though it’s almost not possible to make the marine mammal comfortable because of its body weight, which is not meant to be on the land under direct sun.
After the mammal has rested, attempts are taken to refloat the mammal using a stretcher or sling at high tide. “Abroad, at rehab centres, they feed the animals if they are able to keep them in a water pool with enough space for it to move and eat. They then assess their respiration and stress hormones before releasing them back to sea, if that’s at all possible,” Dr Sutaria said. But it all starts with informing the right authorities. “Usually, local people have the contacts of local officers. We reach out to locals, hotels, resorts and the research teams to train them,” said Dr Sutaria.
At Mandarmani, Dr Balakrishnan figured that the whale had died almost a week ago, probably from an injury. He has been studying underwater earthquakes in the region and doesn’t rule it out as a probable cause of death.
Once primary investigations are over, forest department staff cleanse the whale carcass, stuff it up with around 80 kilograms of salt to aid decomposition and prevention of any infection, and bury it on the coast. The location of the grave is duly recorded. “We have received permission to exhume the skeleton. We will allow around 2-2.5 years for it to decompose, and probably around the end of 2022, check on its condition,” said Dr Balakrishnan.
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