Zooplankton Pooing Microplastics to Ocean Floor
Altering the tiny creatures' excrement turns out to have potentially serious environmental consequences.
You already knew that plastic pollution in the oceans was disgusting, but you probably didn't realize it was this disgusting.
A new study by researchers from England's University of Exeter and Plymouth Marine Laboratory concludes that microplastics – those tiny pieces smaller than a millimeter in size, which are particularly hazardous to marine life -– are altering the sinking rates and other properties of zooplankton feces.
What happens is that the tiny marine creatures are consuming the plastic and excreting it. But the amount of polystyrene in the fecal pellets is making them lighter than normal, causing them to sink more slowly to the sea floor.
So why is that a big deal? Zooplankton feces, as it turns out, actually perform an important function in the marine environment, by transporting carbon and nutrients into deeper waters. That not only provides nourishment for animals who live in the ocean, but it also helps the oceans to store carbon, an important thing for controlling climate change.
Now, however, with the pellets sinking more slowly, there's a greater opportunity for them to be ingested by marine animals. That transfers the plastic to their stomachs, where it can cause all sorts of harm.
"As these fecal pellets sink, they take the plastic with them." the study's leader, Exeter scientist Matthew Cole, explained in a press release. "This could be an important route by which floating plastic litter is removed from the sea surface down to the ocean depths."
Zooplankton themselves are consuming plastic at an alarming rate, according to a 2015 study by Canadian scientists. That's also worrisome in its own right, because as the bottom of the aquatic food chain, they're eaten as food by many larger animals, and they pass along plastic in that fashion as well.
A vast range of marine organisms, including fish, turtles, seabirds, and invertebrates are known to consume plastic debris.
Other researchers have estimated there are over five trillion bits of microplastics floating in the ocean, and microplastics have been found in the intestinal tracts in a quarter of fish and a third of shellfish sold at markets in the United States.
Zooplankton are consuming microplastic at alarming rates.
The month of June honors both National Ocean Month and World Ocean Day (June 8). What better time, then, to check out photos of undersea life and be reminded that things "down there" are just as important as things up here on land. Here, a manatee goes about its day. The manatee, also known as a "seacow," is an air-breathing herbivore listed as a federally endangered species. Manatees are slow moving and can't swim quickly away from boats. This often results in collisions that can kill or injure them.
Life's a beach. Mom and her baby elephant seal roll around in the sand in Ano Nuevo Island, Calif.
A humpback whale breaches in the Gulf of the Farallones National Marine Sanctuary, off the coast of California.
A blue rockfish fans for the camera in Monterey Bay National Marine Sanctuary, in California.
A Southern sea otter, aka,
Enhydra lutris nereis
, wonders what all the fuss is about, at South Harbor, Moss Landing, Calif. The World Ocean Day Photo Contest entrant was Submitted by Dr. Steve Lonhart.
A white-lobed sponge brightens up the scenery. It's one of several images of rarely seen deep-sea animals that were captured on camera in Olympic Coast National Marine Sanctuary during a NOAA expedition. Researchers used a NOAA remotely operated vehicle in waters 328 to 656 feet deep off the Olympic Peninsula in Washington State. The research was funded by NOAA's Coral Reef Conservation Program.
This image brimming with colorful marine life is from the Pearl and Hermes Atoll. It's a huge oval coral reef within several internal reefs and is the second largest among the six atolls in the Northwestern Hawaiian Islands.
Having no backbone isn't always a bad thing! Just ask any octopus. These boneless invertebrates know how to squeeze into (and out of) many a tight spot. They have three hearts, nine brains and blue blood. (Two hearts send blood to the gills, while the third pumper sends it to the rest of the body.)
Rapture Reef sits within the Northwestern Hawaiian Islands Marine National Monument. The monument encompasses more than 140,000 square miles of ocean and coral reef habitat.
A sea turtle swims off of the Hawaiian islands.
This seal is eager to wriggle its way back to freedom, as divers release it from fishing nets. Marine debris -- such as these nets -- makes a serious impact on its surroundings. From being an eyesore on a beach to injuring marine life or stopping a 400-ton vessel at sea, it causes problems that are difficult to ignore.
Grey matter artwork? Nope! It's a sharknose goby (
) propped up on brain coral in the U.S. Virgin Islands.