Ecosystems

Previous studies of shipwrecks in the United Kingdom and the Red Sea have shown that such artificial reefs often create new and different types of habitat than natural reefs.

Fish thrive on WWII shipwrecks

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.

Giant kelp (Macrocystis pyrifera) is a species of kelp (large brown algae)

Kelp forests help the climate

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 larvae being collected at Palmyra Atoll National Wildlife Refuge. This allows researchers to enumerate the number of baby corals settling on a reef.

Corals seek cooler pastures in subtropical waters

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.

Andrew A Shantz places an enclosure over corals on the sea floor at Florida Keys.

Selective fishing of larger parrotfish lets algae flourish

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.

Offshore coral reefs are healthier

Researchers from the Woods Hole Oceanographic Institution (WHOI) and the Centro de Investigaciones Marinas—Universidad de La Habana (CIM-UH) have discovered that offshore coral reefs that are also protected tend to be healthier than nearshore ones.

In the study, seawater from 25 reefs in Cuba and the Florida Keys in the US were tested for nutrients and other parameters that would give researchers a glimpse into the microbial community present.

Using sounds of healthy reefs to attract young fish

Healthy coral reefs are full of sounds of life—with the whistles, pops and grunts of fish, the crackle of snapping shrimp, etc. These sounds travel out through the ocean currents, and “advertise” to young fish to come and settle down at this particular reef ecosystem.

However, when reefs are degraded or dying, the environment falls silent. Literally.

As a result, young fish do not find their way to such reefs, and this exasperates the reef's dire situation.

Seagrass can provide shelter for small marine animals.
Seagrass can provide shelter for small marine animals.

Seagrass essential to fishing industry

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.

Some fish 'farm' their food

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.