Protecting Ocean Ecosystems
How Right Whale Poop Plays an Essential Role in the Ocean Ecosystem
North Atlantic right whales are an iconic New England species that attract tourists and locals alike to the ocean, hoping to catch a glimpse. Research has indicated that North Atlantic right whales also play a key role in marine ecosystems in an unexpected way. Ironically, these whales might just be most important during their least attractive moments: when they poop.
Whales Bring Essential Nutrients to the Surface
In the ocean, microscopic marine algae called phytoplankton need nutrients such as nitrogen, phosphorous, and iron to photosynthesize. These nutrients are often a scarce resource in shallow, sunlit waters where phytoplankton live because nutrients are constantly sinking. When the animals that consume phytoplankton and others higher up in the food chain defecate, and later when they die, the nutrients in their fecal matter and bodies drift down into deep water. This phenomenon is known as the biological pump.
Scientists long assumed that marine mammal feces acted in the same manner, sinking into the ocean’s depths and becoming inaccessible to light dependent phytoplankton. However, researchers found that whale poop actually floats. So, when whales feed in the deep and come to the surface to defecate, they transfer thousands of tons of nutrients to surface waters. In contrast to the downward “biological pump,” this upward transport of nutrients by whales and other marine mammals has been termed the “whale pump.”
Essentially, fecal matter from whales helps supply the base of the food chain by providing the nutrients necessary for phytoplankton to photosynthesize. In a healthy ecosystem with enough phytoplankton productivity, animals higher up the food chain can thrive, including important species for New England’s fisheries. The nutrient contribution of whales is also especially important because phytoplankton sequester carbon from the atmosphere, helping to regulate the Earth’s climate, and release oxygen into the atmosphere, supplying half of the oxygen we breathe.
Endangered Right Whales are Necessary in the Gulf of Maine
In a recent study, researchers led by conservation biologist Joe Roman collected fecal matter samples from North Atlantic right whales in the Bay of Fundy to examine the role that they play in nutrient cycling. Right whales feed throughout the water column, so the researchers hypothesized that their feces contribute to the movement of nutrients up into shallower waters.
They found that important nutrients, specifically nitrogen and phosphorus, are in fact made available to phytoplankton at the surface via right whale feces. The nutrient inputs of right whales and other whales are especially important during the summer in the Gulf of Maine, when nutrients at the surface can approach zero, limiting the growth of phytoplankton. And, according to Roman, whales transport more nitrogen in the Gulf of Maine than all rivers in the region combined.
This key role in the ecosystem is another reason why we cannot afford to lose the right whale. With only about 411 North Atlantic right whales left in the population – and potential extinction by 2040 – protecting the North Atlantic right whale is more important now than ever before.
Lawrie is an Ocean Conservation Intern at CLF.