Chennai: The Tamil Nadu forest department, which lacks expertise in marine biology, has closed the issue related to the massive stranding of 80 pilot whales along Thoothukudi coast last January. With the post mortems providing no breakthrough and all other research into the deaths not throwing up any clues, the state wildlife wing has now brought closure to the issue saying the event was a complex and global phenomenon that was entirely natural.
“Through our resources we pushed some of the mammals back in to the sea but most of them were found dead the next day. There are no leads from the investigations so far”, said a top wildlife official at state forest headquarters. To a query over whether any samples were taken from the dead animals for tests, the official said samples were sent to the Wildlife Institute of India.
The Fisheries Research Institute wanted the skeleton of the beached animal preserved. In principle, permission was given to exhume a carcass, but even that failed to materialise, the officer admitted.
However, the only respite is the Dean of Fisheries College and Research Institute in Tiruchendur deployed a team of marine scientists to examine the mass stranding.
The scientific team, headed by Dr A. Srinivasan, made observations on the water temperature, salinity and dissolved oxygen content of the inshore region, which were found to be normal.
The experts admitted that though the exact reason could not be ascertained, it could be predicted in this case that these whales may have chased prey (small fish like sardines and other inshore school of fishes) in intertidal areas during the last phase of the highest high tide period (new moon day periods) and must have got stranded later because of the shallow depth created by the receding tide, during which time they must have faced the problem of disorientation resulting in massive death.
“There are documented data to refer to in TN dating back to 40 years, but there is no baseline study. Marine mammals stranding is an uncommon event in Tamil Nadu and the reason behind their stranding should be explored scientifically," said T. Maruthupandi, assistant project manager, Rajiv Gandhi Centre for Aquaculture, MPEDA, Union ministry of Commerce and Industry.
In most cases related to mammals stranded on beaches, the carcasses have revealed microplastics in their guts and an in-depth examination of whale gut could have thrown some light on toxic pollution in pilot whales, the marine biologist Marudhupandi said.
