The ikan kuning you eat with your nasi lemak could become extinct in your lifetime - unless consumers turn to sustainable sources for the fish, a nature group has warned.

To help consumers make ethical food choices, a guide that assesses the environmental sustainability of 41 popular seafood species in Singapore was launched yesterday by the the World Wide Fund for Nature Singapore (WWF-Singapore).

Of these, 31 species, or about three out of four, are unsustainable, said the group, which called for more to be done before these species disappear from the oceans - and menus - forever.

Other than the ikan kuning, the list of fish that consumers should avoid or eat less of include the Indian threadfin, also known as ngoh hur, which is used in fish porridge, and silver pomfret.

WWF-Singapore chief executive Elaine Tan said Singapore has a "big role" to play in protecting the oceans as it is one of the biggest consumers of seafood in the world per capita. Each person here consumes about 22kg of seafood yearly, more than the global average of 20kg.

"We are squandering one of our greatest natural resources by failing to manage our fish stocks sensibly," said Ms Tan. "The Seafood Guide empowers everyone in the supply chain to make conscious choices that prevent the further exploitation of fish stocks."

The silver pomfret, for example, is caught in the South China Sea by trawling. Boats drag large nets along the seabed, catching almost everything in their path. They can damage coral reefs and, at shallow depths, catch marine turtles.

According to the guide, sustainable seafood options include the cod, Atlantic salmon and red tilapia.

A sustainable seafood business forum, which brought together retailers, hoteliers, restaurants and suppliers from the seafood industry, was held yesterday.