Cargo ships carry billions of tiny stowaways in their bellies
Every two weeks, massive vessels transplant enough seawater to fill twenty thousand Olympic pools, turning dark ship hulls into high-speed shuttles for microscopic predators and invasive larvae.
To maintain stability on the high seas, a single large cargo ship pumps more than 50,000 tons of local seawater into its ballast tanks. This water acts as a massive, unintended aquarium, capturing billions of plankton, bacteria, and larvae before the vessel departs for a distant continent. Because these microscopic passengers are often invisible to the naked eye, they bypass traditional hull inspections, allowing ships to function as biological Trojan horses that can cross entire ocean basins in under fourteen days.
Continue Reading in App
1 more paragraph · plus a 2-question quiz