Aquatic garbage could be collected and sequestered using "artificial whales" that swim through affected areas "filter feeding" as baleen whales do. They would sort items by size and material using 3D printed electroactive polymers in conjunction with 3D printed plastic filters and other components. Larger sea creatures would avoid them. Smaller ones capable of free swimming which were captured would be given the opportunity to swim out of the tank they were funneled into whereas the garbage would stay behind. Plankton could be sorted from garbage by employing their daily cycle of depth changes. The smallest organisms would pass completely through the system. As technology progressed, smaller and smaller bits of garbage could be sorted from living organisms using 3D printed membranes and textured surfaces. A similar method could be used to harvest specific organisms without harming unwanted ones.
Specific sustainability aspects
Aquatic pollution has a tremendous negative effect on human health, ecosystems and economies. Cleaning our freshwater and seawater should be among the highest priorities of governments and businesses all around the world. Recent advances in 3D printing size and material capabilities makes it possible for complicated assemblies to be fabricated econimically. The most complex biological shapes can be analyzed and reproduced and tested so there would be no need to set up an expensive infrastructure to prototype or manufacture these devices.Finally, the entire "whale" can be made of biodegradable material so it can be disposed of at the end of its useful life.