Researchers from the University of Vermont studied four species of baleen whales—gray, humpback, North Atlantic and North Pacific right—to assess their role in oceanic ecosystems. These whales feed in subpolar waters for most of the year, fattening up before migrating thousands of miles to warm-water breeding grounds in winter.

At their breeding and birthing sites, they release significant nutrients through urine, feces, skin and dead whale bodies. The study, published in Nature Communications, found that the whales annually transport more than 4,000 tons of nitrogen and 45,000 tons of biomass to nutrient-poor coastal areas in the tropics and subtropics.