The deleterious consequences of humanity’s “plastic footprint” are many, some known and some yet to be discovered. We know that plastics biodegrade exceptionally slowly, breaking into tiny fragments in a centuries-long process. We know that plastic debris entangles and slowly kills millions of sea creatures; that hundreds of species mistake plastics for their natural food, ingesting toxicants that cause liver and stomach abnormalities in fish and birds, often choking them to death. We know that one of the main bait fish in the ocean, the lantern fish, eats copious quantities of plastic fragments, threatening their future as a nutritious food source to the tuna, salmon, and other pelagic fish we consume, adding to the increasing amount of synthetic chemicals unknown before 1950 that we now carry in our bodies.

We suspect that more animals are killed by vagrant plastic waste than by even climate change — a hypothesis that needs to be seriously tested. During our most recent voyage, we studied the effects of pollution, taking blood and liver samples from fish as we searched for invasive species and plastic-linked pollutants that cause protein and hormone abnormalities. While we hope our studies will yield important contributions to scientific knowledge, they address but a small part of a broader issue.

The reality is that only by preventing synthetic debris — most of which is disposable plastic — from getting into the ocean in the first place will a measurable reduction in the ocean’s plastic load be accomplished. Clean-up schemes are legion, but have never been put into practice in the garbage patches.

The National Oceanic and Atmospheric Administration in the United States supports environmentalist groups that remove debris from beaches. But the sieve-like skimmers they use, no matter how technologically sophisticated, will never be able to clean up remote garbage gyres: There’s too much turbulent ocean dispersing and mixing up the mess.

The problem is compounded by the aquaculture industry, which uses enormous amounts of plastic in its floats, nets, lines and tubes. The most common floats and tubes I’ve found in the deep ocean and on Hawaiian beaches come from huge sea-urchin and oyster farms like the one that created the oyster-buoy island we discovered. Those buoys were torn from their moorings by the tsunami that walloped Japan on March 11, 2011. But no regulatory remedies exist to deal with tons of plastic equipment lost accidentally and in storms. Government and industry organizations purporting to certify sustainably farmed seafood, despite their dozens of pages of standards, fail to mention gear that is lost and floats away. Governments, which are rightly concerned with depletion of marine food sources, should ensure that plastic from cages, buoys and other equipment used for aquaculture does not escape into the waters.