YOUR WEEKLY BRIEFING FROM PARLEY
New research from the Monterey Bay Aquarium Research Institute (MBARI) shows that plastic debris less than 5mm across, known as microplastic, is common from the surface to the seafloor. It may also be entering marine food webs in the deep ocean. The study suggests that most of this microplastic is coming from consumer products.
Some samples were collected just offshore, but most were collected about 25km from shore, in the deep waters of Monterey Canyon. The results surprised the team. They found nearly identical concentrations of microplastic particles near the surface and in the deepest waters surveyed. Perhaps more startling, they found roughly four times the concentration of microplastic particles in the midwater range (200 to 600 meters down) than in waters near the surface.
The researchers also looked at concentrations of microplastic particles in specimens of two marine species that filter-feed in the water column: pelagic red crabs and giant larvaceans (above). The team found microplastic in all of the animal specimens they surveyed.
Meanwhile, another study has found that people are likely consuming at least 50,000 particles of microplastic a year and breathing in a similar quantity. The true number is likely to be many times higher, as only a small number of foods and drinks have been analysed for plastic contamination. The scientists reported that drinking a lot of bottled water drastically increased the particles consumed. The health impacts of ingesting microplastic are unknown, but they could release toxic substances and penetrate human tissue.
In 2016, Princess Cruise Lines paid a multi-million dollar penalty for illegally dumping oil-contaminated waste into the sea. Now, the company is facing new violations including discharging plastic into waters in the Bahamas, falsifying records and interfering with court orders. An audit of one ship found that food waste had been mixed with plastic straws and discharged at sea. Cruising is anything but green – even the most efficient new ships can emit three to four times as much CO2 per passenger-mile as a passenger jet.
After years of inaction, the U.S. House of Representatives passed a bill this week directing federal authorities to assess the risks of ocean acidification. Scientists have shown the oceans are becoming more acidic as they absorb greater quantities of carbon dioxide from the atmosphere. In the Gulf of Maine, researchers have documented that acidic conditions stunt clam growth and make it so difficult for baby oysters to build their first shells that they often die before they can complete them.
It’s not too late to save our oceans, argues one researcher. “A proven solution to allow populations to recover is to stop fishing. It worked for the great whales, and it works in marine reserves. Internationally, almost 90% of zones called 'Marine Protected Areas' are not marine reserves because they allow fishing. Such MPAs really aim to apply stricter fishing rules for local food security, not protect wildlife in natural conditions. We need better management of fishing everywhere. The entire ocean should be an MPA with some places with no fishing.”