Ecosystems

In 2016, the National Oceanic and Atmospheric Administration (NOAA) undertook a closer examination of the wrecks of the German U-boat U-576 and the Nicaraguan freighter SS Bluefields, using glass-domed submersibles. The two historically significant and deep (200m) shipwrecks sank near one another on the continental shelf of North Carolina, USA, during World War II.

Kelp is an ecologically and economically important foundation species in California, where forests line nutrient-rich, rocky bottom coasts. It also might alleviate acidification caused by too much atmospheric carbon being absorbed by the seas.

A new interdisciplinary analysis of giant kelp in Monterey Bay off the coast of California shows that near the ocean’s surface, the water was less acidic, suggesting the kelp canopy does reduce acidity.

Coral reefs have been seeking new pastures, as rising temperatures heat up their natural habitats.

Over the last four decades, coral reefs have been progressively shifting their homes from equatorial waters to more temperate regions.

The reason? Climate change.

“Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,” said Nichole Price, a senior research scientist at Bigelow Laboratory for Ocean Sciences and lead author of the paper on the topic.

Scientists at Pennsylvania State University and the University of California, Santa Barbara have discovered that when fishermen selectively catch large and medium-sized parrotfish at coral reefs facing decline due to climate change, algae has a better chance of growing and overtaking the corals.

Nonetheless, according to the research, the reef’s biomass is maintained. This is because even with less of the large and medium-sized parrotfish, there would be many smaller parrotfish that would take their place.

Admittedly, the idea of protecting seagrass is not as “glamorous” as protecting the rainforest, but this marine vegetation is essential to both marine life and humans. A new study by scientists from Cardiff University, Swansea University and Stockholm University, and published in the Fish and Fisheries journal, highlights the global importance of seagrass to fisheries.

“Wherever you find seagrass and people, there is most certainly fishing,” said Dr Leanne Cullen-Unsworth, from Cardiff University’s Sustainable Places Research Institute.

The existence of the reef have come as big surprise because many of the world’s great rivers produce major gaps in reef systems where no corals grow. There was little previous evidence because corals mostly thrive in clear, sunlit, salt water, and the equatorial waters near the mouth of the Amazon are some of the muddiest in the world, with vast quantities of sediment washed thousands of miles down the river and swept hundreds of miles out to sea.

Coral reefs are particularly vulnerable to the ocean acidification process, because reef architecture is built by the accretion of calcium carbonate, called calcification, which becomes increasingly difficult as acid concentrations increase and the surrounding water's pH decreases.