Marine debris continues to litter our beaches, and more of it is on the way if our current weather patterns continue.
Nets, floaters, and other rubbish aren’t just ugly and dangerous to marine life.
They hide small organisms and creatures that could harm our fragile shorelines.
Scott Godwin works with the Hawaii Department of Land and National Resources Division of Aquatics Resources Aquatic Invasive Species (AIS) team. He’s been studying invasive species and marine debris for more than 15 years.
“There’s a lot of stuff out there all the time,” Godwin said, “and Hawaii seems to be in the right place to get that stuff just because of the oceanographic conditions.”
He explained that the current winds and currents have simply been washing debris onshore that would normally otherwise float by the islands and go unnoticed.
The debris poses many dangers. Marine mammals and fish get tangled in floating masses of nets and die.
But many of the transoceanic rafting episodes, as scientists refer to large marine debris, are harmful because invasive species live on them. Since the 2011 Japan earthquake and tsunami, the amount of alien species found on debris landing on Hawaiian shores has increased dramatically.
“I studied a lot of the debris prior to the tsunami and I only really documented one non-native species that had come in from outside of Hawaii,” Godwin said. “When the tsunami happened, then we got a lot of debris that were like plastics and already had these organisms growing on it. We started seeing a lot more alien species.”
Godwin said he’s logged more than 20 different invasive species on marine debris since 2011 and those creatures can hurt Hawaii’s fragile ecosystem.
“There’s always the competition with our native stuff, especially like our opihi and some of our native snails that live in the nearshore,” explained Godwin. “And other macro algaes that can get introduced that can overgrow things. It’s hard to predict what anything is going to do until it actually does it.”
If state and federal organizations know the debris harbors invasive species, why isn’t more of an effort being made to collect it before it reaches the beach?
“It’s extremely dangerous doing these kinds of things from a safety standpoint,” Godwin said. “Things are seen all the time, but its extremely dangerous and we discourage people in the general public to try to intercept these large net debris that are out in the ocean, because it might look like it’s a small piece that’s up on the surface but down below, it’s kind of like an iceberg.”
Kevin O’Brien, a marine debris project lead for NOAA, says it’s not only difficult, it is costly.
“It’s still very spread out,” O’Brien said. “In order to conduct removals at seas, you would spend a lot of time and money on a ship and it becomes prohibitively expensive.
“We haven’t come up with a great way to make that cost-effective,” he added, “so cleaning it up once it reaches the islands and the reefs has been the only way to pull it off efficiently.”
O’Brien works predominantly removing debris from the Northwestern Hawaiian Islands and atolls since it is a marine sanctuary.
“We have conducted a couple of surveys on the main Hawaiian islands via helicopter and a couple of removal efforts on Oahu and Lanai, but it’s been about 10 years since we did any of that,” O’Brien said.
O’Brien said NOAA and other organizations have made efforts to detect debris using drones and satellites, but collecting the debris before it reaches shore is too challenging.
There are a number of volunteer organizations who constantly work in the main Hawaiian islands removing debris.
808 CleanUps and the Kauai chapter of the Surfrider Foundation have worked tirelessly to rid our shorelines of all kinds of debris.
In 2017, 808 CleanUps said it removed more than 25,000 pounds of net debris. The Surfrider Foundation said it collected more than 122,930 pounds of debris, and 57 percent of that was nets.