Coral reefs aren’t just threatened by pollution, ocean acidification and over-heated ocean temperatures. In some places they are being undermined by erosion of the seafloor, U.S. Geological Survey scientists said in a new study that looked at reefs in Florida, the Caribbean and Hawaii.
In the five study sites, the reefs can’t keep pace with sea level rise. As a result, coastal communities protected by the reefs are facing increased risks from storms, waves and erosion.
The degradation of reefs and the subsiding seafloor go hand-in-hand, as sand and other sea floor materials have eroded over the past few decades. In the waters around Maui, the sea floor losses amounted to 81 million cubic meters of sand, rock and other material – about what it would take to fill up the Empire State Building 81 times, the researchers calculated. Continue reading “Sea level rise overwhelming some coral reefs”→
New research will help islands prepare for future coastal hazards
Sometime before Columbus sailed into the Caribbean, a massive ocean upheaval tossed giant coral boulders far inland on tiny island — a sign that there may have a tsunami, or perhaps an extra-powerful hurricane in the region.
The new findings, published in the journal Geosphere, will help coastal planners prepare for unexpected hazards, according to researchers with the U.S. Geological Survey. The boulders were found in the British Virgin Islands at Anegada—a low-lying island named by Columbus in 1493 and located behind a coral reef that faces the Puerto Rico Trench. Continue reading “Mega-waves swept Caribbean corals far inland”→
‘It is the equivalent of having summer for the first time in thousands to millions of years’
Deep sea ecosystems that have barely been explored are at risk from global warming, as low-oxygen zones spread and ocean acidification increaseses. By 2100, organisms deep on the ocean floor may face starvation and sweeping ecological changes, according to scientists from 20 of the world’s leading oceanographic research warned last week.
“Biodiversity in many of these areas is defined by the meager amount of food reaching the seafloor and over the next 80-plus years – in certain parts of the world – that amount of food will be cut in half,” said Andrew Thurber, an Oregon State University marine ecologist and co-author of the study, published in the journal Elementa. Continue reading “Deep oceans at risk from climate change”→
Study says 90 percent of all predatory fish species have been lost from Caribbean coral reefs
Not all Caribbean reefs are created equal, say researchers with the University of North Carolina at Chapel Hill, who recently identified reef areas they are calling “supersites”that could help restore populations of predatory fish needed maintain an ecological balance.
That’s the good news. The bad news is their study also shows that up to 90 percent of predatory fish are gone from Caribbean coral reefs. The research suggests that these supersites should be prioritized for protection and could serve as regional models showcasing the value of biodiversity for tourism and other uses. Continue reading “Can ‘supersites’ anchor coral reef protection efforts?”→
Pollution from Chinese factories is changing the nutrient balance in the ocean, say scientists who studied depositions of chemicals and plankton blooms in the East China Sea. These waters are increasingly threatened by harmful algal blooms that choke off vital fish populations, according to the new study, led by researchers at the University of California, Irvine.
“There has been massive growth in emissions from China’s factories and cars over the past few decades, and what comes out of the smokestacks and tailpipes tends to be richer in nitrogen than phosphorus,” said Katherine Mackey, assistant professor of Earth system science at UCI and lead author of the study, published recently in Frontiers in Marine Science. Continue reading “Pollution from China disrupts ocean ecosystems”→
A new survey of the Great Barrier Reef shows that an ocean heat wave that peaked last March killed up to 95 percent of corals in some parts of the northern reef. And in the aftermath of the worst coral-bleaching event on record, predatory snails are now taking on toll on the remaining corals.
According to the ARC Centre of Excellence for Coral Reef Studies, researchers recently returned to 83 reefs they surveyed at the height of the bleaching event.