A fish species in missing evolutionary link traced

These have special features; they can live on land and in water

CUDDALORE: A rare fish species called “mudskippers” have been recorded by researchers of the Centre for Advanced Study in Marine Biology of Annamalai University at Parangipettai estuary near here.

A rare fish species found in the Vellar estuary at Parangipettai in Cuddalore district

These tiny species, measuring just 67 mm in length and weighing 22 mg, have got special features which enable them to live both on land and in water. Called ‘vaetti uluvai’ in Tamil, they are the missing link between fishes and amphibians in the evolutionary ladder, according to T. Balasubramanian, Director of the Centre.

He told The Hindu that during the survey conducted recently in the Vellar estuary at Parangipettai near here under the University Grants Commission-supported project on gobiid fishes the researchers identified a mudskipper variety, Periophthalmus variabilis.

The Director said the species were aptly called mudskippers because they had mudflats as their habitat and had the habit of skipping or hopping around. The fish had got protruding rounded eyes that could move in all directions.

Its pectoral fins resembled more of the forelimbs of frogs, with which it attains mobility and climbs on to vegetations. Mr. Balasubramanian further said that the fish digs burrows in mudflats that have a gentle slope towards the sea and have a depth of up to one-and-half metre.

During high tide, the burrows would get filled with seawater and during low tide the waves would withdraw, allowing to make its appearance, he added.

Principal Investigator V.Ravi, also Assistant Professor in the Centre, said mudskippers played an important role in the food chain. They feed on fish eggs, nematodes, smaller crabs and insects, and, are, in turn, food for birds and otters. Mr. Ravi said mudskippers would lay eggs within the burrows and male fishes would oxygenate the eggs by blowing air. The eggs would not get washed away because they had an adhesive filament that made them stick to the walls of the burrows. This sensitive creature would swirl in the burrows at the very sight of a predator.

The mudskippers have medicinal quality and are being used as a remedy for anaemia and to prevent frequent urination in children.

Mr. Ravi observed that in China, South Korea and Japan the mudskippers were cultured extensively for food and the Centre would evolve a suitable strategy for its proliferation through captive breeding.

A.V. Ragunathan – From THE HINDU

Noise levels affecting sea mammals

CHENNAI: “The underwater noise levels today are ten times more than they were a few decades ago, which is a serious worry for life on land and water because sustainable ocean space makes way for sustainable land space,” said S.K. Bhattacharya, Head, Department of Ocean Engineering, IIT Madras.

He was delivering a special lecture on ‘Acoustics’ for school students organised by the Tamil Nadu Science and Technology Centre in collaboration with Madras India Regional Chapter of the Acoustical Society of America and Acoustical Foundation here on Saturday.

S.K. Bhattacharya, Head, Department of Ocean Engineering, IIT-M, interacts with school students at a programme on acoustics in Chennai on Saturday. Founder of Acoustical Foundation H.S. Paul (second from right) is in the picture. — Photo: K..V.Srinivasan

Listing the various ill-effects of underwater noise pollution on marine mammals, Professor Bhattacharya said that anthropogenic noise due to activities like commercial shipping, Sound Navigation and Ranging (SONAR) activities and hydrocarbon-related engineering activities contributed a great deal in increasing the noise levels.

Marine mammals exposed to underwater noise pollution suffer from displacement, trauma, stranding, internal injuries, eye haemorrhaging, and sometimes even death, he added.

“The marine mammals exposed to Low Frequency Active Sonar (LFAS) above a certain level can sometimes face mass extinction,” he said.

The other significant activities detrimental to the sustenance of a healthy marine system, he added, were dredging, drilling and exploration, near shore construction and military activities on the sea.

On the various statutory bodies of seawater regulation, regulatory mechanisms on water and other environmental issues, Professor Bhattacharya said that the ocean taxonomy needed to be documented better.


Stranding response programme for endangered marine species suggested

Wildlife Institute of India says this will strengthen cause of research

CHENNAI: The Wildlife Institute of India, Dehradun, has suggested to the Centre the initiation of a stranding response programme for endangered species of marine animals, WII scientist B.C. Choudhury said here on Thursday.

Addressing a two-day national consultation workshop for identification of research gaps in coastal and marine biodiversity conservation hosted by the Ministry of Environment and Forests, Prof. Choudhury said a stranding operation (involving rehabilitation of rare species that wash up on the shores sick or injured), provided scientists a unique opportunity to study these creatures out of their natural habitats.

Pointing out that many of the threatened species such as the dolphins, river terrapins and horse shoe crabs remained least studied specimens, Prof. Choudhury said a stranding programme could strengthen the cause of research in this direction.

Prof. Choudhury said India’s coastal and marine ecosystems were under increasing threat in spite of the great importance accorded to balancing livelihood issues and economic output to the national GDP along the 8,500-km coastline with ecology conservation. He advocated a multi-Ministry collaborative approach to the conservation agenda for the coastal and marine environment.

Prof. Choudhury pointed out that traditionally, the contribution of densely populated coastal regions to national wealth was much higher than that of land-locked systems. The coastal zone was home to half the world’s population, two-thirds of the largest cities and contributed half the tourism earnings.


Prof. Choudhury spelt out as the priorities macro-level research in coastal and marine habitats, floral and faunal diversity values and identification of natural and anthropogenic threats. Some of the least-studied systems, in spite of their significant ecological importance, were sand dunes, estuaries, salt marshes, inter-tidal mud flats and sea grass beds, he said.

In her inaugural address, Aruna Basu Sarkar, Chief Conservator of Forests and Director of the Gulf of Mannar Biosphere Reserve Trust, called for integration of policy framing, implementation, research and community engagement for an effective coastal and marine biodiversity conservation programme.

K. Siva Kumar, WII scientist, said the workshop was the starting point in the consultative process to evolve a roadmap for future research on coastal and marine biodiversity conservation in India.

The specifics of the workshop include identification of research gaps, prioritisation of research, mandating specific roles for partnering institutions.


Reasons for marine pollution explained

At ‘pollution response seminar-cum-workshop’

Tuticorin: The Indian Coast Guard Station, Tuticorin, has organised a ‘pollution response seminar-cum-workshop’ to take stock of the preparedness in combating the likelihood or possible threat of marine pollution along the coastal districts of Tuticorin, Tirunelveli and Kanyakumari. The programme was organised on the premises of ICGS here on Tuesday.

Stating various reasons for marine pollution, Commandant Udhal Singh, Station Commander, Coast Guard Station, Tuticorin, who inaugurated the session, said that the entire stretch of 190 km coastal line from Kilakarai (Ramanathapuram district) to Kanyakumari could face an environmental threat, owing to oil spill which might happen because of transportation by shipping of huge quantity of crude oil to the Tuticorin Port Trust.

TIPS:Commandant Udhal Singh, Station Commander, Coast Guard Station, Tuticorin, addressing a seminar on Tuesday.

Harmful to aquaculture

Marine pollution might happen due to collision, grounding of tanker carrying oil, discharge of residues and oil mixture by the ship at sea causing harm to aquaculture.


The sensitive marine animals were also facing annihilation because of the polluted waters at sea. “Some of the resource agencies which are required to support Coast Guard in regard to duties of Central Coordinating Agencies for response to marine pollution are Indian Navy, Oil and Natural Gas Corporation (ONGC), Indian Oil Corporation (IOC), oil refineries, Oil India Limited, major ports, Ministry of Surface Transport, Ministry of Environmental and Forest, Ministry of Agriculture, Department of Ocean Development, coastal state authorities, DG Shipping, Mercantile Marine Department, Shipping Corporation of India and Central Marine Fisheries Research Institute, he said.

“These are required to be in possession of requisite equipment in combating any oil pollution at sea”, Mr. Udhal Singh added. The Coast Guard personnel made a presentation of various risk factors against a backdrop of oil spillage at sea. They also explained the methodology of detecting the oil spill, which could be executed under the influence of air surveillance.

Meanwhile, several search operations for surveying the possible oil slick movement were shown, with power point presentation.

Special measures were being taken to protect the coastal environment from pollution by mass cleaning of shoreline along the coast. The consequences of marine activities following the accidental risk of oil spill were also highlighted during the schedule.

The personnel from the coordinating agencies enunciated the oil spill disaster contingency plan.

Representatives from the district administration, IOC, Tuticorin Port Trust, SPIC Limited, Fisheries Department and Coastal State Board participated.

From The Hindu