As global temperatures rise and humans continue to pollute the world’s oceans, coral reefs are showing more signs of irreversible damage, and a 600-mile-long reef just discovered at the mouth of the Amazon river is no exception.
Abnormally high sea temperatures kill tiny marine algae that are essential to coral health, which causes the reef bleaching that’s been reported in greater severity around the world. As global temperatures reach all-time highs, bleaching is becoming a greater concern for all coral ecosystems.
The newly discovered reef near the Amazon is also in danger because of oil drilling, the scientists say in a study published Friday in the journal Science Advocates.
“In the past decade, a total of 80 exploratory blocks have been acquired for oil drilling in the study region, 20 of which are already producing,” the article reads.
It says the blocks will “soon be producing oil in close proximity to the reefs,” and “such large-scale industrial activities present a major environmental challenge.”
High levels of fishing in the area present yet another threat to the reef, oceanographer Patricia Yager told the Los Angeles Times. But since environmental-impact assessments were conducted before the discovery, it’s not clear how much damage drilling and fishing might cause.
“Isn’t that always the case?” she said. “You don’t know what you’ve got until it’s gone.”
The good news is that the new Amazon reef appears to be thriving, despite unlikely conditions in the muddy waters at the mouth of the river, where there is no light, no photosynthesis and tiny amounts of oxygen. The scientists say the reef’s conditions are relatively “impoverished” compared to most corals, which thrive in clear, sunlit salt water.
“Traditionally, our understanding of reefs has focused on tropical shallow coral reefs which harbor biodiversity that rivals tropical rainforests,” said Rebecca Albright, an oceanographer and coral researcher at the Carnegie Institution for Science, in an interview with the Atlantic.
“As tropical coral reefs are in decline worldwide (we’re currently in the midst of the third global coral bleaching event), it may become more important to understand which organisms can tolerate harsher conditions,” she added.
Unfortunately, it may be too late to salvage corals like that in the Great Barrier Reef; a recent aerial survey, reported by ABC in Australia, revealed that 95 percent of the northern reef is now severely bleached. Bleaching is occurring in varying degrees of severity along the 1,600-mile-long reef, indicating widespread and sometimes permanent damage to the natural World Heritage site.
Other once-healthy reefs around the world, such as that surrounding Kiritimati – a tiny, remote island nation in the Pacific Ocean – are also bleached or almost completely dead.
“From a global perspective, the level of warming is about to enter the danger zone for coral reefs and it is certainly arguable that it is already too late for some of these systems to ‘adapt naturally,’” said Michael Oppenheimer, a professor of geosciences and international affairs at Princeton University, to Washington Post.
“We and others thought coral reefs would be the first global indicator of emergence of dangerous warming and events have borne out that expectation.”