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.
New lab experiments suggest that increasing ocean acidification could take a big bite out of the economically important cod fishery in the North Atlantic. The research suggests that the buildup of CO2 in the ocean could double the mortality of newly-hatched cod larvae.
Members of the German research network BIOACID quantified the impacts, showing that recruitment could decrease to levels of one quarter to one twelfth of the recruitment of the last decades. Cod have already been under intense fishing pressure for decades, and the new study, published in the online journal PLOS ONE, identifies climate change as an emerging new threat. Continue reading “Ocean acidification seen as huge threat to Atlantic cod”→
So many moods in the deep blue sea, changing from day to day, and even from hour to hour. This set features shots from a jaunt along the Mediterranean coast of Italy and France, including a few moon rise time exposures. The cove image from the French island of Port Cros, a national park off the coast of Hyères. The moonrise shots are near Cap Corsaire.
Researchers call for balance between mining and ecosystem protection
New research shows that proposed mining on the seafloor of the Pacific Ocean would likely have a huge impact on marine biodiversity. A study published in the journal Scientific Reports, documents an “impressive abundance and diversity among the creatures” on the seafloor in the Clarion-Clipperton Zone — an area in the equatorial Pacific Ocean being targeted for deep-sea mining.
“We found that this exploration claim area harbors one of the most diverse communities of megafauna (animals over 2 cm in size) to be recorded at abyssal depths in the deep sea,” lead author Diva Amon said in a press release.
The researchers explained that a combination of biological, chemical and geological processes formed a high concentrations of polymetallic “manganese” nodules on the deep seafloor in the CCZ–an area nearly the size of the contiguous United States. These nodules are potentially valuable sources of copper, nickel, cobalt and manganese, among other metals, which has led to an interest in mining this region. Continue reading “New study documents biodiversity in proposed deep sea mining zone”→
Continued illegal gill net fishing cited in push for ban on Mexican seafood
In what could be a last-ditch effort to save imperiled vaquita in the Gulf of California, conservation advocates are urging the Obama administration to launch economic sanctions against Mexico to halt that country’s trade in totoaba. According to the Center for Biological Diversity, the sanctions would be justified because Mexico is violating the Convention on International Trade in Endangered Species (CITES) by not enforcing the ban on totoaba trade.
New study helps explain how carbon flux changes over time
The shells of tiny ocean organisms called foraminifera have once again given climate researchers huge clues about the long-term carbon cycle in the world’s oceans. The information helps show the buildup of heat-trapping greenhouse gases will affect the climate.
Study identifies bleaching and mortality thresholds for imperiled coral reefs
The steady rise in ocean temperatures projected for the next few decades will put more and more corals at risk of bleaching, as the warm water simply overwhelms their thermal tolerance mechanisms.
Recent research along the Great Barrier Reef shows that corals have been able to survive past bleaching events because they were acclimated to warmer temperatures by being exposed to a pattern of gradually warming waters in the lead up to each episode. But global warming is likely to change that, the scientists said.
Before long, temperature increases of as little as 0.5 degrees Celsius may push many corals over the edge as the warm water causes them to expel the algae-like dinoflagellates that help keep them alive and give them their color.
Lead author Dr. Tracy Ainsworth from Coral CoE said bleaching is like a marathon for corals.