Whales play a crucial part in natural iron fertilization of oceans, because they go deep underwater to eat a large amount of krill, which are iron-rich, and dej

Whales play a crucial part in natural iron fertilization of oceans, because they go deep underwater to eat a large amount of krill, which are iron-rich, and deject near the surface, because they need to breathe. Their dejections fertilize the phytoplankton which lives near the surface. Because they need to move between deep and shallow water, and because they travel over large distances, whales act as nutrient pumps for the ecosystem.