In muddy waters somewhere off Brazil’s northern coast lies a secret, previously undiscovered Coral Reef.
The reef covers 3,600 square miles and has been unearthed in the most unlikely of places – at the mouth of the Amazon River.
Published 22 April 2016 in Science Advances, the most extensive study to date reveals the reef – stretching from the French Guiana border to Brazil’s Maranhão state – may constitute an entirely new type of ecological community and is likely to support many new species previously unknown to science.
Researchers had a vague idea of its existence but until recently, had no inkling of just how large and diverse it really is. “This is something totally new and different from what is present in any other part of the globe,” says Fabiano Thompson, an oceanographer at the Universidade Federal do Rio de Janeiro in Brazil. “But until now, it’s been almost completely overlooked.”
The reef sits at depths below the Amazons large plume of muddy fresh water that is so large it can be seen from space.
“You wouldn’t expect to have gigantic reefs there, because the water is full of sediment and there’s nearly no light or oxygen,” Thompson says. The pH, salinity and amount of sedimentation and light that characterise a reef habitat are drastically different compared with other reefs around the world which is what makes this one so unique.
One striking feature of the reef was its high densities of Rhodoliths, a type of red algae that is often confused with coral because of its calcium carbonate structure and bright colours. These tennis ball-shaped organisms often covered the Brazilian reef floor. Sponges were the other major component of the reef system, with 61 species found. The team also counted 73 fish species, 35 algae, 26 soft corals, 12 stony corals and more.
Thompson and his researchers are appealing for protection of the Amazon Coral Reef as major oil and gas companies are exploring areas nearby for drilling.
There is much left to be discovered however, as this study although the largest survey ever conducted, only covers around 10 percent of the entire underwater habitat.
Source: Smithsonian Mag