Why Whale Urine Plays A Crucial Role In Marine Life

Even biologists only get a fleeting look at the lives of whales. Many species, especially deep-diving whales, remain largely unknown.

Scientists are gaining a deeper understanding of the vital role whales play in marine ecosystems and the services they provide. Recent studies indicate that even whale urine is crucial for Earth.

The Whale Pump: How Whale Feces Fertilize the Ocean and Fuel Marine Life

Earlier research highlighted the importance of whale feces to ecosystems, as these massive mammals transport nutrients from the deep waters where they feed to the surface.

This process, known as the “whale pump,” boosts the photosynthetic activity of plankton, which forms the foundation of the food web. Nutrients are not evenly distributed throughout the ocean, and in some regions, phytoplankton populations are limited due to a lack of essential elements like iron.

Certain whale species undertake extensive migrations across the oceans. Humpback whales (Megaptera novaeangliae), for example, hold the record for the longest mammal migration, traveling approximately 10,000 kilometers and helping to transport nutrients across entire ocean basins. In addition, the whale pump has some impact on carbon cycling and storage.

Whales also contribute to nutrient cycling in the ocean by disturbing the seafloor during feeding. Gray whales, (Eschrichtius robustus), for instance, forage for invertebrates along the ocean bottom, stirring up sediments that release nutrients like nitrogen, phosphorus, and iron.

Whale Falls: Deep-Sea Oases of Life

Another important area of study focuses on the unique “oasis” ecosystems formed around whale carcasses in the deep sea. These remains support a variety of species—from hagfish (Eptatretus deani) and sleeper sharks (Somniosus pacificus) to crustaceans, mollusks, nematodes, and bacteria. The large bodies of great whales, rich in lipids stored in their bones, provide vital sustenance for numerous organisms and foster miniature ecosystems on the ocean floor.

However, one ecosystem benefit provided by whales had gone largely unmeasured—until recently: their urine.

A recent study in Nature Communications suggests that the urine of baleen whales may play a vital role in ocean ecosystems. Certain whale species are capable of producing as much as 950 liters of urine daily, allowing them to transport nutrients to tropical regions that are typically nutrient-poor. Many baleen whales, including humpbacks and gray whales, feed in the nutrient-rich polar and subpolar waters during the summer, then migrate in large numbers to equatorial breeding grounds—often concentrated in relatively small areas—during the winter.

As whales migrate, they transport various forms of organic matter—including placenta, urine, feces, and in some cases, their carcasses if they die en route. For instance, the study highlights that gray whales typically spend the winter feeding across multiple locations in the North Pacific and then gather in a few small bays along the California coast during summer.

The Great Whale Conveyor Belt: Giants Driving Global Nutrient Transport

The researchers describe how gray, humpback, and North Atlantic right whales (Eubalaena glacialis) help move carbon and nitrogen to nutrient-poor tropical regions in a process they refer to as the “great whale conveyor belt.” On a global scale, this migration results in the transfer of over 46,000 tons of biomass—including the whales themselves and the nutrients they carry—and nearly 4,000 tons of nitrogen annually.

Whale urine accounts for the majority of this nitrogen movement, which in turn stimulates phytoplankton growth and boosts photosynthesis. This enhancement in photosynthetic activity could potentially remove around 18,180 tons of carbon from the atmosphere. Other large baleen whale species likely contribute to this process as well, though limited data on their habits and movements makes it harder to measure their impact precisely.

Unfortunately, the study estimates that historical whaling has diminished whales’ ability to transport nutrients to just about one-third of what it once was.

Other species that are vital to nutrient cycling have also been impacted by human activities. Migratory seabirds and fish that travel from the ocean to freshwater systems play a major role in moving phosphorus from the sea to land—another key nutrient that supports photosynthesis.

Wildlife as Nutrient Couriers: How Animals Transport Ocean Riches to Land

Predators like bears, otters, and eagles that feed on fish migrating from the sea into rivers also help transfer ocean nutrients to land through their droppings. Moose play a similar role, moving significant amounts of nutrients from water to land as they graze on aquatic plants.

Conversely, animals like hippos move nutrients from land back into aquatic environments. However, these large land animals generally don’t match whales in either the volume of nutrients they move or the global scale at which they operate.

Today, whales face numerous threats to their survival, including collisions with ships, pollution, overfishing, and climate change. This recent research highlights how critical it is to protect both whales and the marine environments they inhabit.

While the extent to which whales can help address the climate crisis by enhancing photosynthesis and influencing the global carbon cycle remains uncertain, each new discovery reveals more about their essential role in maintaining healthy ocean ecosystems.

Read the original article on: Phys.Org

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