Since the discovery of an amazing coral reef system at the mouth of the Amazon River, there has been much excitement among the marine biologists community. Overturning a generally accepted understanding that shallow reefs are only found in areas with intense sunlight, this reef has been thriving under a cover of nutrient-rich silt, where the river and the Pacific Ocean collide. The silt loading in the Amazon River is frequently so heavy that visibility is less than half a meter; it is so low, in fact, that divers can barely see their own hands. It is no wonder the reef was not discovered sooner, in spite of the fact that it may stretch more than 600 miles from the mouth of the river into the Amazon Basin (Vidal, 2016).
What exactly is living in those murky depths is still a mystery, but scientists are diving in several locations to find out. The prospect of discovering a vigorous community of numerous coral and fish species (such as what is found in Australia’s Great Barrier Reef) is not likely, and initial reports are that the reef contains primarily sponges and non-photosynthetic coral, such as Gorgonians. These type organisms include sea fans and tube corals that are filter feeders and trap food particles floating through the water, rather than gathering light from the sun to produce food.
Whether the Amazon River reef is a rare occurrence or whether there may be other hidden river reefs stretching far into low visibility rivers remains to be seen. Nonetheless, the ecology of coral reefs will somehow have to account for this very unusual occurrence.
Other Relevant Articles:
For those who are very interested in recent developments of this new-found Reef system, this published scientific journal offers some insight:
Vidal, John. “Huge Coral Reef Discovered at Amazon River Mouth.”www.theguardian.com. Guardian News and Media, 22 Apr. 2016. Web. 17 May 2016.