Meet the Plankton That Eats Microplastic
Scientists in California have discovered that a species of plankton called giant larvaceans will eat microplastics near the surface of the ocean; their excretions then fall to the seafloor, where they are likely to be consumed by other marine life.
These 4in-long (10cm) plankton live inside 3ft (0.9m) houses, sticky webs that they use to catch food. When these houses become clogged, they cast them off.
In early 2016, researchers at the Monterey Bay Aquarium Research Institute (MBARI) sent a remote operated vehicle (ROV) into the Monterey Canyon off the California coast and released tiny plastic beads near larvaceans’ feeding filters: 11 of 25 animals consumed the plastic and excreted the beads in their fecal pellets.
In a study published in the journal Science Advances, MBARI researchers calculated that the plankton’s microplastic-containing fecal pellets would sink 1,000ft (300m). Larvacean houses can sink as fast as 2,600ft (800m) a day, according to previous studies.
“These results suggest that larvacean houses and fecal pellets could quickly transport microplastics from near-surface waters to the deep seafloor,” the MBARI said in a statement.
“There’s a lot of work being done studying plastic in the guts of seabirds and fish,” MBARI principal engineer Kakani Katija said. “We’re currently working on experiments to study the concentrations of microplastics at different depths in the ocean, using water samples and maybe even cast-off larvacean houses.”
Deep-Sea Medicine
While corporations and countries are targeting the seabed to mine for copper, cobalt and other minerals, British researchers are investigating the potential for developing new medicines from the bacteria that live on deep-sea sponges.
Scientists at the University of Plymouth say they have cultured more than 100 previously unknown bacteria strains from bottom-dwelling sponges to make antimicrobials capable of killing MRSA, an antibiotic-resistant infection usually contracted in hospitals.
“We believe that deep-sea sponges contain diverse populations of new cultivable and non-cultivable bacteria,” said Mathew Upton, an associate professor of medical microbiology at the university. “These represent a substantial uncharacterized and untapped source of bioactive molecules which could help meet the urgent need for new antimicrobials and have other health benefit applications.”
The university said that more than 12,000 people a year die from superbugs like MRSA in the United Kingdom.
The researchers said they also plan to probe the deep-sea bacteria’s cancer-fighting potential.
Loss of Sea Ice Pushes Walruses Ashore
As Arctic Ocean sea ice continues to contract due to rising temperatures, walruses are being forced ashore earlier and earlier.
During the first week of August the marine mammals, which depend on the ice as a platform for hunting prey, made their earliest appearance yet on a barrier island off Alaska’s northwest coast, according to the United States Fish and Wildlife Service.
There are now about 2,000 walruses on the island, the Associated Press reports. The large number puts the animals at risk of dying in stampedes triggered when something startles them.