Visakhapatnam: Of the total 125 species of marine mammals found across the world, around 26 of them, mostly dolphins, are distributed along the Indian coast.
According to the first ever detailed study conducted by the Central Marine Fisheries Research Institute (CMFRI) over a few years on the distribution of marine mammals, dolphins were recorded more in the south eastern Arabian Sea and southern Sri Lankan waters.
The Indo-Pacific bottle-nose dolphin was the most frequently sighted species whereas the spinner dolphin was dominant in terms of abundance. The long-beaked common dolphin, Indo-Pacific humpbacked dolphin and sperm whale were also recorded at frequent intervals.
The CMFRI conducted 46 opportunistic surveys on board research vessel Sagar Sampada in the Indian Exclusive Economic Zone (EEZ) and the contiguous seas to collect data on the distribution of these mammal species. It took 6,554 hours of sighting effort to locate a total of 8,838 mammals.
The CMFRI initiated a research project, “Studies on Marine Mammals of the Indian EEZ and the Contiguous Seas”, with funding support from the Centre for Marine Living Resources and Ecology and the Ministry of Earth Sciences in two phases since 2003 for an understanding of the cetacean species' diversity, distribution and abundance.
The study is the only project dedicated to marine mammal research in the country. The findings were published in a book “Marine Mammal Research and Conservation in India” by the CMFRI.
“Marine mammals, especially dolphins in the Indian EEZ, are one of the least studied animals. They are also very important in the marine eco system as they prey on predators of fish. They are also fishermen-friendly as they show them the way. But unfortunately, they get entangled in fishing nets and become part of their catch.
However, due to increased awareness about the importance of dolphins and the consequences of catching them, their deaths have declined of late and their numbers are said to have increased,” former director of CMFRI Dr G. Syda Rao told this correspondent.
Expressing concern over marine pollution caused by humans and industry, Dr Rao suggested laying underwater pipes along 3-4 km from the coast into the sea where there are oceanic under currents which can dilute the waste thrown either by humans or industries, thus combating the pollution that also kills marine mammals.
It was during his tenure as director that Marine Mammal Research and Conservation in India was published, the research having been done by scientists E. Vivekanandan, R. Jeyabaskaran, KSSM Yousuf, B. Anoop and K.S. Abhilash.
