Whale Farts: Gas Clouds Underwater
Whales are the largest animals that have ever lived on Earth — and their bodily functions are correspondingly monumental. Whale farts, as researchers call cetacean flatulence, were only systematically documented in recent decades. Drone footage shows massive gas clouds rising from the water — and marine biologists have begun to scientifically analyze these emissions. What they found inside is surprisingly illuminating.
How Do Whales Even Fart?
Whales are mammals and digest food fundamentally similarly to land animals — with one important difference: a whale's digestive tract is enormous. Baleen whales like the blue whale filter up to 4 tons of small crustaceans (krill) and fish daily. Toothed whales like dolphins and orcas digest whole fish and squid. In both cases, gut bacteria ferment undigested remnants and produce gases. The gas is released anally — like land animals. Above the water surface it appears as clusters of bubbles that become visible when surfacing. Some researchers first documented whale farts while following whales with drones — the gas cloud is unmistakable.
What's in a Whale Fart?
In 2017, an Australian research team under Joe Roman (University of Vermont) analyzed samples from whale farts for the first time, collected with drones from breath (blows) and gas samples from the water. The results were surprising: whale farts contain bacterial cultures, hormones, DNA, and fatty acids — a treasure trove for researchers wishing to study whale health non-invasively. The gas mixture itself contains methane, carbon dioxide, and hydrogen — similar to other mammals. The sheer quantity is enormous due to body size, but whales eat comparatively simple, easily digestible food (krill), keeping gas production per kilogram of body mass relatively low.
Whales as Climate Savers? The Nutrient Cycle
Ironically, whales are not climate villains despite producing methane. On the contrary: whales are considered important carbon stores and promoters of marine productivity. A large whale stores up to 33 tons of CO₂ in its body over its lifetime — this sinks to the ocean floor upon death. Additionally, whales fertilize the oceans through their excretions (feces rich in iron and nitrogen) and thereby promote phytoplankton growth, which in turn sequesters CO₂. Calculations show that restoring global whale populations to pre-industrial sizes would be equivalent to planting 1.7 trillion trees in terms of CO₂ sequestration. The whale fart is thus part of a remarkably useful ecosystem service.
The 'Fart Drone Approach' in Whale Research
The so-called SnotBot method — developed by Ocean Alliance in collaboration with MIT — uses drones to collect samples from whales' blows (exhaled breath) as they surface. The drones fly directly over the whale when it surfaces and capture breath and gas samples on silicone plates. This method is far gentler than conventional biopsy methods (arrows into whale flesh) and provides information about hormone levels, viruses, bacteria, and stress indicators. Bacteria found in the samples partly originated from the whales' digestive tracts — showing that breath air and gut gases are partially connected. The method is revolutionizing whale medicine.
Did you know?
- A blue whale produces more gas daily than a human does in an entire month — due to the sheer amount of krill it eats each day.
- Ocean Alliance's 'SnotBot' drone collects whale health data from the breath gas of whales — non-invasively and from the air.
- Despite their methane production, whales are net carbon stores — their bodies sequester far more CO₂ than their gut gases emit.
- Whale farts were only systematically documented with drone cameras in the 2010s.
Fun Fact
A video of a humpback whale releasing a massive underwater gas bubble directly into a diver's face went viral in 2017 and has millions of views on YouTube. The diver — a whale biology researcher — reported it felt 'overwhelming' and smelled. He described it as one of the most unforgettable moments of his career — not necessarily in a positive sense.
Sources
- Roman, J. et al. (2014). Whales as marine ecosystem engineers. Frontiers in Ecology and the Environment, 12(7), 377–385.
- Lavery, T.J. et al. (2010). Iron defecation by sperm whales stimulates carbon export in the Southern Ocean. Proceedings of the Royal Society B, 277(1699), 3527–3531.
- Ocean Alliance (2019). SnotBot: Using drones to revolutionize whale research. oceanalliance.org.