Taking Care of Mother Ocean
By Barbara Mayer
We’ve all seen pictures of our Earth as photographed from space: a small, blue marble with swirls of clouds. That tiny splash of blue in the surrounding cold, dark void is our primordial home; it is our aquatic nest.
We have been fouling our nest, littering our ocean. What is marine litter; what is marine debris? America’s National Oceanic and Atmospheric Administration (NOAA) has created “Marine Debris 101” as part of the global effort to educate us. They tell us that marine debris is “any persistent solid material that is manufactured or processed and directly or indirectly, intentionally or unintentionally, disposed of or abandoned into the marine environment or the Great Lakes.”
|Marine debris piled up on the beach.
Marine debris is a problem of the global ocean. Trash that blows or washes into the ocean in one place can last for months or hundreds of years to wash ashore thousands of miles away. When I took a walk on Waimanalo beach, I found plastic aquaculture tubes from Japan. During another walk, I met a lady from Japan; she told me that small, unprocessed pieces of plastic intended for industry in Hawai`i have washed up on her beach at home. The large currents that stir the perimeter of the North Pacific circulate our trash, making it our common problem.
In addition to marine debris riding currents at the edge of the ocean, other currents have concentrated trash toward the center of the North Pacific. This concentration has casually been referred to as the “garbage patch of the Pacific.” What a disturbing metaphor! Oceanographers have begun to correlate this concentration of debris with an area of wind driven surface ocean water convergence. Cooler, wind driven waters meet warmer, sub-tropical waters in this area. This Sub-Tropical Convergence Zone (STCZ) can extend for 5000 miles in roughly an east-west direction. It’s found within the latitudes of northern Baja, Mexico to Portland, Oregon; the precise location is dependent upon season and other meteorological and oceanographic factors still being studied.
The STCZ itself is a natural, phenomenon; functioning as a natural oasis in the middle of relatively low productivity ocean waters. When the nutrient-rich, cooler water meets impoverished warmer water at the Sub-Tropical Convergence Zone, phytoplankton thrives, and so does a remarkable food chain of small critters. It’s a veritable salad bar for migrating sea turtles and albacore tuna. On occasion, when the STCZ cycles into a southerly position, its waters also enrich the Northwestern Hawaiian Islands and Papahanaumokuakea Marine National Monument. But remember: marine debris has been added to the salad fixings.
The marine life that live in the Monument might define marine debris more graphically. It’s what you see during a beach walk that doesn’t belong. It’s what can wrap around the neck or limb of a sea turtle. It’s what clogs the stomach of many Laysan Albatross that nest by the hundreds of thousands at Midway Atoll National Wildlife Refuge, in the Monument.
NOAA, the US Fish & Wildlife Service and the State of Hawai`i have the responsibility to protect and conserve the Monument’s healthy atolls, rocky pinnacles and surrounding waters, which stretch for 1200 miles northwest of the populated Hawaiian islands. How do you do that when you’ve got huge quantities of marine debris washing up on reefs and beaches? Over the last 10 years the Monument management agencies, and many other partners, have removed over 560 tons of marine debris from the shallow reefs of the Northwestern Hawaiian Islands, but new debris keeps arriving. An estimated 52 metric tons of new debris arrives every year according to a recent study by NOAA’s Pacific Islands Fisheries Science Center. So, how do you stop the debris from reaching the reefs in the first place
What you do is invent an airborne robot! You work with an Alaskan company of talented engineers to invent a small, relatively inexpensive robotic glider, or Unmanned Aerial System, dubbed “Malolo 1,” the Hawaiian word for flying fish. Malolo 1 successfully passed land-based trials. It’s now aboard the NOAA Ship Oscar Elton Sette, heading for the Sub-Tropical Convergence Zone. When the ship arrives, the glider will go through about 10 days of maneuvers.
The hope is that Malolo 1 will facilitate detection of marine debris in the open ocean, especially big snags of net, rope and line. This information can then be used to deploy a team to either pick up the debris, or tag it with satellite drifter buoys. The satellite tags will help marine debris researchers understand the path this debris follows as it moves around the Pacific. In the future, if this project is successful, similar gliders can be deployed from vessels at sea to help locate and collect debris before the debris is carried into shallow waters, where it would damage coral reefs and drown wildlife.
Of course, it would be better if the nets never got into the ocean in the first place, so individuals still need to do their part to properly dispose of nets and other fishing gear. However, for the nets that are floating in the ocean now, this technology can go a long way toward removing them before they wash ashore. Malolo 1 is helping us care for our aquatic nest!