Govind D Belgaumkar/The Hindu

• Naval activity endangers unique ecosystem that supports a large number of ornamental fish  

Mangalore, May 26: A unique ecosystem — coral reefs discovered in 2005 at Netrani Island, off Murdeshwar — is already under threat.

A large number of ornamental fish survive on the coral reefs there.

The Bangalore-based Karnataka Biodiversity Board has already been apprised of the situation.

P.U. Zacharia, senior scientist at the Toothukudi unit of the Central Marine Fisheries Research Institute (CMFRI), headed the team that discovered the coral reef.

(A coral reef is a mound or ridge of living coral, which forms a hard colourful substance formed from the bones of very small creatures. Found in shallow marine waters, they resemble a beautiful garden with a variety of flowers. The world’s largest Great Barrier Reef off the north-eastern coast of Australia extends for 2,000 km.) The first large-scale study was conducted, based on a request by the Biodiversity Board, to prepare an inventory of coastal biodiversity in the 25,000 sq. km area of marine waters off coastal Karnataka, which contributes around six per cent of the fish production in the country every year. Mr. Zacharia, who was here on Thursday to participate in a one-day seminar on biodiversity organised by the local unit of the CMFRI, said the underwater survey at Netrani Island was carried out by professional divers.

It revealed, for the first time in the entire west coast, a “very unique” biodiversity-rich area with some of the rarest species of life underwater, he said.

He expressed regret that the island’s ecosystem was under threat from the Indian Navy’s shelling/shooting practice exercises.

Unexploded shells were found in the waters. The activity should be stopped immediately to save the ecosystem, he said. He suggested that the island be protected as a marine reserve with regulated ecotourism.

A detailed investigation was required to document the marine biodiversity of the area covering all seasons.

Eighty-nine coral fish species were found in the area, including 27 that are new to the Indian coast.

Out of the nine grouper fish species identified at the island, Cheilinus undulates (Humphead wrasse) was endangered and Rhincodon typus (whale shark) vulnerable, Mr. Zacharia said. Netrani Island, which boasts two types of coral reefs, also has seven seaweed species, 12 jelly fish species, six sponge species, 92 finfish species, 17 crab species, four lobster species and three sea snake species, among others. Nethrani Island is 19 km away from the shore.Coral reefs have been found around Nicobar Island (42 genera) Lakshadweep Islands (28), Gulf of Mannar (26) and Andaman Islands (25).

Elsewhere on the Karnataka coast, a rare octopus species, a rare lingula species , a species of hermit crab, five species of starfish, two species of sea urchins, one species of sea cucumber, a sun fish species (called Mola mola), three species of endangered sea turtles, three species of sea snakes, three species of dolphins and four species of whales were found, he said.

In all, there were 390 fish species belonging to 24 orders and 118 families.

This formed 15.3 per cent of coastal fishes reported from the Indian coast.

It also had 40 species of sharks, rays and skates, as well as 350 bony fish species.

He said the accidental release of certain species through ballast water carried by foreign ships arriving in New Mangalore and Karwar ports posed a bio-invasion threat along the Karnataka coast. The coast was a repository of 1,386 (nine per cent) of 16,173 species of marine life found in India, he said.