Photo: Manu San Félix/National Geographic
The Olu Malau archipelago, in the Solomon Islands, turns out to harbour the largest coral colony in the world. A team of scientists and filmmakers reported the discovery in National Geographic on 14 November. This record-breaking structure, consisting of nearly one billion genetically identical polyps, is 32 metres long, 34 metres wide and 5 metres tall. That is three times larger than the previous record holder, a coral colony nicknamed ‘Big Momma’, which stands 6 metres tall with a circumference of 41 metres. Scientists estimate the Pavona clavus colony to be around 300 years old. Smaller corals in the surrounding area are in poor condition due to rising water temperatures, but the giant colony is faring surprisingly well. The discoverers attribute this to the greater depth at which the coral grows, where the effects of rising temperatures are less pronounced. One of the researchers described the find to the BBC as a ‘beacon of hope’.
The coral has no established common name in English, but is known in various countries as ‘shoulder coral’, owing to the knobby projections that resemble shoulders. The full scientific name Pavona clavus was first described in 1846 by the American zoologist James Dwight Dana, who discovered the species during an expedition in the Pacific Ocean. Although no explicit etymological explanation exists, the genus name Pavona may derive from the Latin word pavo (peacock). This is unlikely to refer to the vivid colours of a peacock, however, since corals belonging to the genus Pavona are rather drab in colour. It could instead refer to the characteristic patterns often found on these corals, comparable to the patterns on a peacock feather. With the species epithet clavus, Dana alludes to the columnar projections that are characteristic of this coral species; clavus is Latin for ‘nail’. Just as the peacock proudly spreads its feathers, this impressive coral colony reminds us of the wonders that still lie hidden in nature.