According to a paper published in the scientific journal Science Advances on April 22nd, researchers have discovered a thriving coral reef hidden beneath the muddy waters at the mouth of the Amazon River. The world’s largest river in terms of volume, the Amazon is a place of superlatives that provides a home for a bevy of species found nowhere else in the world. This latest discovery confirms the river’s status as one of the most unique ecosystems on Earth.
Coral Reef Discovered Near Mouth of Amazon River
The reef was discovered by a team of scientists from the University of Georgia and the Federal University of Rio de Janeiro, who were in the area conducting research on the Amazon River plume. The plume refers to the freshwater expelled from the river itself into the ocean, and it was at the meeting point of the two that the scientists first found evidence of a coral reef hidden beneath the surface. Although the main purpose of the expedition was to take samples at the river mouth, the team also decided to investigate an anecdotal report in a scientific article published in the 1970s, which spoke of scientists catching reef fish in the same area.
The scientists used a dredge to bring up samples from the bottom habitat, and in doing so discovered fish, starfish, sponges and coral. According to the paper’s co-author, professor Patricia Yager, the team was “flabbergasted” to find evidence of a reef in an environment so totally different to those in which one would expect to find a thriving coral community. Unlike the light-filled, clear waters of tropical reefs, the waters of the Amazon are opaque with sediment. Despite this, the team found no fewer than 73 reef fish species living on a reef that they now believe to cover some 3,600 square miles, stretching from French Guiana to Brazil’s Maranhão state.
The southern part of the reef is apparently more prolific than the north. In the south, greater light penetration allows for increased biodiversity, while the northern stretches of the reef are populated mostly by sponge species. Nevertheless, Yager was astonished by the variety of life found beneath the freshwater plume, saying “we brought up the most amazing and colorful animals I had ever seen on an expedition.” However, the scientists’ joy at their unexpected discovery is tempered by the fact that, like so many of the world’s coral reefs, the Amazonian reef is under threat from ocean acidification, rising sea temperatures and plans for oil extraction in the immediate area.
According to the paper in Science Advances, the Brazilian government has sold 80 blocks for oil exploration and drilling at the mouth of the Amazon; some of these are already producing oil, and may be located directly on top of the newly-discovered reef. If extraction continues, this exceptional ecosystem will undoubtedly be destroyed. It remains to be seen whether or not the team’s discovery will trigger any protective legislation, and whether or not in can be implemented in time to save the Amazon’s newest treasure.
