Papua New Guinea released 4 stamps on the reef fish on 6th April 2011.Groupers are one of the most highly regarded groups of reef fish species, valued for daily food needs and in the luxury restaurant trade. Globally there are 162 species in the grouper family, almost one third of which occur in Papua New Guinea.
The largest reef fish in the world is the giant grouper, reaching over 2 metres in length. Its smallest grouper cousin grows to just 20 cm. Both species are found in Papua New Guinea.Grouper biology makes them particularly vulnerable to overfishing, much more so than most other fish species on coral reefs.
Many groupers can live 30 years or more and need many years to become sexually mature. Some have the fascinating habit of changing their sex, with adult females turning into adult males in response to changes in their social groups; for example, if too many males are lost from the population by heavy fishing, females will become males to replace them.