Ecosystems

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.

Working on Palmyra atoll, around 1,000 miles south of Hawaii, a team of researchers from the University of California Santa Barbara became aware of the fish's farming habit when they noticed many bite marks in specific areas of algae growing on dead coral.

They followed these patches through time and found parrotfish were feeding heavily in each patch for a short period of time. Then, the fish would allow that exact location to recover before returning to harvest the algae again.

The research team from University of Western Australia arrived at this conclusion after a study involving two coral reefs. At one of the reefs (Scott Reef), shark hunters had been legally permitted to hunt sharks while the other reef (Rowley Shoals) was situated in a marine protected area.

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.

New research suggests that major hurricanes, though devastating to humans, have a minimal impact on salt marshes. The Boston University study reveals coastal ecosystems are more at risk of erosion by waves from moderate storms than from full-fledged tropical storms. In eight different marshes studied in the United States, Italy and Australia, extreme storm events accounted for less than one per cent of erosion.

Many years of restraint and restrictive fishing quotas seem to finally have paid off. Within a decade the stocks of spawning cod have almost doubled

Though levels of cod in the North Sea are not yet what they were pre-crisis, a remarkable recovery is well under way and advancing. Along with cod and plaice stocks of herring, haddock, hake, Norway lobster, common dab and witch (Torbay sole) are also improving .

Coral reefs make up some of the most biologically diverse habitats on Earth and face many threats such as coastal pollution, dredging and disease. However, some of their most widespread threats involve warming ocean temperatures, solar radiation and increased ocean acidification. It is from these threats that corals are finding refuge under the red mangroves.