The Napoleon Wrasse, also known as So Mei in Cantonese, is a popular and expensive dish in seafood restaurants in Hong Kong. But the large, dark blue marine fish, often steamed with a sprinkling of seasoning, is on the verge of extinction. Overfishing is one of the main reasons for the rapid decline of the species. World Wide Fund Hong Kong (WWF) and Ocean Park are conducting a joint campaign to raise public awareness of this endangered species. The Napoleon Wrasse has always enchanted divers with its friendly, charming nature. Unlike other fish, they are not afraid to approach divers. Sometimes, the fish will allow the divers to touch them. They will even follow divers, with their eyes rolling continuously like a curious child exploring its surroundings. The species is the biggest in the Wrasse family and lives in the warmer waters of the Pacific and Indian Oceans. The fish have a life span of around 30 years (some live up to 50), can grow up to 2.3 metres long and weigh more than 180 kilograms. It takes five to seven years for the fish to develop into an adult that can reproduce. A young Napoleon Wrasse looks very different from an adult. Apart from the small size, the young have stripes which disappear as they grow up. They also change colour, from a pale blue-green to a deeper, dazzling shade. Amazingly these fish can change their sex. They can be male one day and female the next, depending on the demand for each gender. When there is an opportunity a female can transform herself into a 'super male' with a distinctive hump on its head. In the past decade, nearly two-thirds of the total Napolean Wrasse harvest were sold in Taiwan, Hong Kong and Singapore. Most Wrasse imports to Hong Kong come from Indonesia. The fish are captured using sodium cyanide, a toxic compound which is dissolved over coral reefs. The chemical damages the reefs and can also kill other fish. Most Hong Kong restaurants sell young Napoleon Wrasse, causing a headache for environmentalists who claim that the fish are eaten before they can reproduce. This leads to increased fears about their becoming extinct within the next 10 years. A 2kg Napoleon Wrasse can fetch as much as $2,000 in Hong Kong. You can follow these tips provided by WWF and Ocean Park to help protect marine animals: Be aware of what you eat in restaurants. Don't eat the Napoleon Wrasse. Eat hatchery-reared fish whenever possible. Avoid eating immature reef fish. Just remember, extinction cannot be reversed. It is forever. WWF has an online signature campaign for those who want to show their support to endangered marine species at www.wwf.org.hk .