They discover that whale urine is an elixir for oceans

In 2010, scientists discovered something that, a priori, may sound unpleasant, but that has healthy effects for marine ecosystems: whales take nutrients from the depths but defecate on the surface, transporting fundamental resources in their feces for the growth of plankton. Now, a new study led by researchers at the University of Vermont takes a step further and reveals that they also transport huge amounts of nutrients horizontally, along whole oceanic basins, from rich and cold waters where they feed to warm costs near Ecuador where they look and give birth. The results have just been published in the magazine ‘Nature Communications‘.

“These coastal areas usually have clear waters, a sign of a low level of nitrogen, and many have ecosystems with coral reefs,” explains Joe Roman, a biologist at the University of Vermont and main author of the research. “The movement of nitrogen and other nutrients can be important for the growth of phytoplankton, or microscopic algae, and provide food to sharks and other fish, as well as many invertebrates.”

The study estimates that in the oceans around the world, large whales (such as free whales, gray whales and humpback whales) transport about 4,000 tons of nitrogen each year to coastal areas with low nutrient levels in tropics and subtropics. Not only that: they also generate more than 45,000 tons of biomass, since not only urine and excrement act as a kind of ‘fertilizer’ for the sea, but also the skin remains and the bodies of the died whales.

A kind of giant conveyor belt

The authors have called this phenomenon ‘the great whale conveyor belt’, because, for example in the case of humpback whales, which travel from the Alaska Gulf, where they feed, to Hawaii, a more closed area in which they appear, these animals transport until twice the nutrients of those who would arrive through the natural physical forces.

“You can also think of this phenomenon as a funnel, because whales feed in large areas, but they need to be in a relatively confined space to find a couple, reproduce and give birth,” says Roman. “And at first, young do not have energy to travel long distances such as mothers.” That is, these cetaceans ‘enrich’ the waters in which their young will spend their first moments of life.

In addition, whales are probably staying in shallow and sandy waters because it cushions their sounds. “Mothers and newborns are called all the time, they remain in communication- indicates Roman- and do not want predators, such as the orcs, or the males of humpback whales in reproduction, they notice their presence.” This means that nutrients distributed in the vast ocean are concentrated in much smaller coastal and coral ecosystems, “such as when sheets are collected to make fertilizer for the garden.”

In summer, adult whales feed on high latitudes (such as Alaska, Iceland and Antarctica), where tons of fat fattened and feed on Krill and Arenque. According to recent investigations, the humpback whales of the North Pacific win about 14 kilos a day in spring, summer and autumn. They need this energy to make a long trip: Barbadas whales migrate thousands of kilometers to their winter breeding areas in the tropics. And all this without eating.

They are not the only example: gray whales travel almost 11,000 kilometers between food areas against Russia and breeding areas along Baja California. And the humpback whales of the southern hemisphere migrate more than 8,000 kilometers from the food areas near Antarctica to the mating sites against Costa Rica, where they burn about 90 kilos a day, while large amounts of urea rich in nitrogen urinate. And telling that a study carried out in Iceland points out that the fin whales urinate about 1,000 liters daily when they eat, it is a more than remarkable contribution to the environment.

«Due to their size, whales can do things that no other animal does. Life live on a different scale, ”says Andrew Pershing, oceanographer of the non -profit organization Central and another of the study authors. «Nutrients arrive from the outside, and not from a river, but through these migratory animals. It’s great and changes our way of thinking about ecosystems in the ocean. We do not think that other animals apart from humans have an impact on a planetary scale, but the whales do.

Researchers have also wondered what the nutrient contribution of this phenomenon would be before industrial whale hunting, back in the nineteenth century, and estimate that it was surely three or more times greater. “Many people think that plants are the lungs of the planet, which absorb carbon dioxide and expel oxygen,” says Roman. «But animals play an important role in the transport of nutrients: for example, sea birds transport nitrogen and phosphorus from the ocean to the earth in their feces, which increases the density of plants in the islands; And now we have discovered this from whales. Animals form the planet’s circulatory system, and these cetaceans are the extreme example ».