Reasons we call whale’s fertilizers of the ocean
With the yearly winter migration in the Southern hemisphere Humpback whales and Southern Right whales come up to their breeding grounds. The main reason they don’t stay in warmer waters all year round is food. Antarctic waters have a big primary production and produce a lot of their favorite food (krill). In return whales give back their feces (ocean fertilizer).
When thinking about animals one thing we try to avoid is their feces. On land feces from cows and horses have been used as a fertilizer for a long time. In the oceans fish on the coral reefs are seen as fertilizers for the algae growth, but the larger animals (whales) are the biggest fertilizers of them all.
The world’s ocean surface is lacking iron and this is a limiting factor to plankton growth. Offshore winds carry sand with high iron content out to sea, but there is no land close enough to the Southern ocean for this to happen. Still, the Southern ocean is one of the largest plankton producers and that’s due to whale feces. Whale feces is rich in iron so when they poo, it becomes a fertilizer for the plankton to grow better. Krill eats plankton. More plankton in the Southern ocean means more krill can grow, creating more food for the whales. These findings are good news for whales.
Fishing fleets around the world complain about marine mammals and birds eating all the fish and decreasing the amount of fish they can catch, while it’s the opposite. Whales help the plankton growth and create a food source for the fish. This increase in primary production also helps decrease the carbon in the atmosphere. Plankton uses a lot of carbon to grow, thus carbon end up in the food chain (eaten by zooplankton) or as dead plankton sink to the bottom of the ocean. The amount of carbon in the atmosphere is too high and decreasing it with natural processes is the best way to help the planet.
So whale poo is important for both plankton growth and the future of the planet.