Poop Proves These Antarctic Penguins Survived A Lot Of Volcanic Eruptions

penguin-poop — A gentoo penguin poops onto the snow near Potter Cove, King George Island. Steve Roberts/British Antarctic Survey

The proof is in the poop: Scientists say analyzing historic penguin waste has shown them that a particular Antarctic group of the flightless birds has persevered through several devastating volcanic eruptions in the last 7,000 years to narrowly avoid extinction.

Gentoo penguins on Ardley Island, one of Antarctica’s closest points to the tip of South America, have had surges and dips in their population in the thousands of years since they first settled the area. Now scientists have said that ancient penguin poop indicates some of those dips coincided with volcanic eruptions and falling ash.

ardley-aerial — An aerial view of Ardley Island, where gentoo penguins have narrowly avoided extinction for thousands of years. Steve Roberts/British Antarctic Survey

Their study in the journal Nature Communications says at least three of the penguin population surges “were abruptly ended by large eruptions from the Deception Island volcano, resulting in near-complete local extinction of the colony, with, on average, 400-800 years required for sustainable recovery.” Deception Island, which is near Ardley Island, “is a highly active volcano.”

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The historic penguin poop for the study came from local rock samples.

With some of those samples, “we were struck by the intense smell of the guano in some layers and we could also clearly see the volcanic ash layers from nearby Deception Island,” lead author Steve Roberts, from the British Antarctic Survey, said in a statement from that group. “By measuring the sediment chemistry, we were able to estimate the population numbers throughout the period and see how penguins were affected by the eruptions.”

Deception Island volcano’s eruptions would have caused something like a penguin version of Pompeii.

“An eruption can bury penguin chicks in abrasive and toxic ash, and whilst the adults can swim away, the chicks may be too young to survive in the freezing waters,” BAS penguin ecologist Claire Waluda said. “Suitable nesting sites can also be buried, and may remain uninhabitable for hundreds of years.”