A new study has revealed that baleen whales including species such as blue, fin, minke, and humpback whales play a far greater role in ocean health than previously understood. Their waste releases vital nutrients like nitrogen, phosphorus, and iron into the water, which can increase ocean primary productivity by up to 10%, according to research published in the Proceedings of the National Academy of Sciences.
For years, scientists knew whales helped recycle nutrients, but this is the first time their precise impact on marine productivity has been measured. Researchers collected and analyzed feces and urine samples from minke and fin whales to determine nutrient concentrations. They then used ecosystem models to estimate how the nutrient release from several baleen species affects phytoplankton microscopic plants that form the base of the ocean food web.
The results showed that baleen whales collectively release over 815 tons of nitrogen and 325 tons of phosphorus daily in the Nordic and Barents Seas during feeding season. Nitrogen, mostly released through urine, and phosphorus, found in feces, are essential for phytoplankton growth. These nutrients directly enhance photosynthesis, leading to a stronger marine food web and greater carbon absorption from the atmosphere.
The study found that whales have the most significant impact in nutrient-poor regions, such as the northern Barents Sea and Norwegian Sea, where primary production increased by as much as 10% in late summer. Minke whales, though smaller in size, contribute the most nutrients overall due to their higher population numbers.
This boost in productivity cascades up the food chain benefiting zooplankton, fish, and even commercial species like salmon and herring. Researchers observed up to a 10% rise in mesozooplankton biomass in areas where whale nutrient input was high, improving feeding conditions for larger marine animals.
Besides supporting marine biodiversity, whale-driven productivity contributes to carbon sequestration, as phytoplankton absorb carbon dioxide during photosynthesis. By helping the ocean lock away more carbon, whales indirectly play a role in mitigating climate change.
The findings emphasize that protecting whale populations does much more than conserve a species it sustains the very foundation of ocean ecosystems. Scientists now plan to refine their models by adding more data on whale migration, nutrient composition, and excretion depth, as well as studying contributions from other marine species.
In essence, every time whales feed and excrete, they are fertilizing the ocean, turning it into a more productive, balanced, and climate-resilient ecosystem.