Chapter 6 · Try it yourself

Plastic on the Menu

Out in the gyre, a speck of plastic and a speck of plankton are about the same size, and plenty of animals can’t tell them apart. Add microplastic to the base of a North Pacific food web and follow it up, one step at a time.

Part 1: Follow the plastic

Step 0 of 7

Food web.

Who eats whom

Look closer at one animal

Phytoplankton

No plastic yet

Does it pile up at the top? Mercury does: it builds up in each step of a food chain (biomagnification). For the plastic pieces themselves the evidence for that is weak, because most pieces pass through guts. The bigger open questions are the chemicals that come with plastic and what tiny particles do inside bodies.

Part 2: The raft

A lost fishing crate tangled in net drifts into the patch. The open ocean has few hard surfaces, so anything that floats becomes real estate.

Time adrift

A floating crate.

Illustrative drawing, not to scale: real hitchhikers range from specks to a few centimeters.

Meet the riders

Just lost

Open-ocean natives
0 kinds shown

Coastal newcomers
0 kinds shown

Pick a rider

—

Choose one of the riders to meet it.

What scientists found: of 105 pieces of debris collected in the patch in 2018–2019, 70.5% carried coastal species. Researchers counted 37 kinds of coastal invertebrates against 9 open-ocean kinds, most of them from western Pacific coasts such as Japan’s, and some were clearly breeding (Haram and colleagues, 2023).

Why it matters: the open ocean used to be a barrier that coastal life could not cross alive. Long-lasting plastic turns it into a bridge.

Simplified model: a small slice of a real food web with only a few links shown, and a step-through order chosen for clarity. Facts are from single studies and are not averages for whole populations: zooplankton, Desforges and colleagues (2015, northeast Pacific); salps, Brandon and colleagues (2020, North Pacific); lanternfish and other small fish, Boerger and colleagues (2010, North Pacific Central Gyre); predatory fish near Hawaii, Choy and Drazen (2013); Laysan albatross, Smithsonian Ocean and US Fish and Wildlife Service; sea turtles caught as bycatch by Pacific longline boats, Clukey and colleagues (2017); market seafood, Rochman and colleagues (2015). Raft: Haram and colleagues (2023, Nature Ecology & Evolution); gooseneck barnacles, Goldstein and Goodwin (2013); sea skaters, Goldstein and colleagues (2012); floating neuston, Chong and colleagues (2023, PLOS Biology).