A new study from the University of Vermont published in Nature Communications finds whale pee — yes that’s right, whale pee — is a critical part of ocean ecosystems.
Whales, the biggest animals on earth, travel from the arctic to tropical seas to birth their calves. And the waste they leave there is chock-full of nutrients.
Joe Roman, a researcher at the University of Vermont, answered our questions about whales and what they leave behind.
How many nutrients do whales carry across the ocean, and what are they doing to release them?
“One is through placentas, and whale placentas can be several-hundred pounds when it’s released into the ocean, and we’ve seen sharks feed on those placentas,” Joe Roman said.
“Two is carcasses. What we found that we didn’t expect was that urine is the primary pathway for the essential elements. Why urine? Well, you die once, you have your birth once a year, but you’re peeing every day.”
“And one estimate for fin whales is about 250 gallons a day that they’re peeing. Humans pee about half a gallon, so you can see why, OK, all this — in this case, we were looking at nitrogen — and all this phosphorus is getting into these areas like Hawaii and the Caribbean. If you’ve ever been there, you probably think of clear blue waters. One of the reasons that their waters are so clear is they’re nutrient limited, often nitrogen limited,” Roman said.
“Whales are bringing in, we estimate, about 4,000 tons of nitrogen per year. We also had about 4,000 tons of biomass coming from Alaska to Hawaii every year.”
That’s comparable to about 20 million Big Macs.
What is the nitrogen doing to support life in tropical ecosystems that are nutrient-poor?
“One way that nitrogen can be picked up is in the phytoplankton or the marine algae. And that’s one of the reasons those areas are pretty clear is because you don’t have a lot of phytoplankton,” Roman said. “If you go off the coast of New England, the waters would be murkier. That can be cycled through to the fish populations in those areas, possibly getting into corals as well.”
Was there anything kind of gross about doing this research?
“It’s never pleasant to step inside a whale that has died, that is stranded and [has] rotted for a couple of days. It’s pretty stinky every day that goes by,” Roman said.
“Right whale feces is one of the strongest smelling and most challenging feces to collect and analyze of any species that I’ve found. Whale pee? We more watch it than collect it.”
In the study, you estimate that before commercial whaling, whales would have transported maybe three times as much nutrients as they are now. How is this cycle changing? Is it threatened by climate change?
“We’ll start with the bad news, good news and then maybe the questionable news,” Roman said.
“Bad news is: for about 1,000 years, we were commercial whaling. And the goal was never sustainability; it was basically serial depletion. You go one place, you harvest them as hard as you can, and you go somewhere else,” Roman said. “By the 1960s, many whale species were on the point of extinction.”
“The good news is in the 1970s and 1980s, the U.S. passed The Marine Mammal Protection Act, The Endangered Species Act and then the International Whaling Commission put a moratorium on whaling. And across 50 years, the response has been — for many species — remarkable.”
“Your last question was about climate change,” Roman said. “It seems unlikely that whale populations, at least in the Southern Hemisphere, will be sustainable as the oceans heat up.”
“And why is that? Because different organisms are going to thrive in a warmer ocean. So one study suggests that krill populations, which support fin whales and humpback whales especially, will decline, and it’s likely that [those whale] populations will decrease with climate change.”
This story was originally published by Vermont Public. It was shared as part of the New England News Collaborative.
