Gentle waves were whispering against the shore. Seabirds were wheeling overhead. A soft breeze blew cool against my face. And all I could smell was… well… crap. Penguin crap, to be precise.

Oh, did I forget to mention this beach was in Antarctica? 

For most people, poop wouldn’t be the most logical topic to write about after a visit to the most beautiful place on the planet. But I’m a mother to a six-year-old boy – so quite a bit of our lives revolve around discussing bodily functions.

So after looking through a few of my many hundred penguin photos, it was no surprise that the conversation inevitably turned to penguin poop.

It turns out that my son is not the only one with a bit of a fascination with penguin poop (technically known as guano). Scientists in Antarctica have found that penguin poop is surprisingly useful for helping to track the movement, and size, of penguin colonies.

The penguins that surrounded me as I sat on the beach that day were adelie penguins. adelie penguins are one of the two true species of Antarctic penguins, nesting on land during the summer, and spending the winter at the edge of the sea ice.

Adelie penguins are classified as near threatened with extinction – mainly due to the effects of climate change. As the oceans warm and sea ice declines, the adelie penguins are finding it harder to find food, and are often losing chicks to starvation.

In some areas of the continent, the numbers of adelie penguins have fallen by up to 65 per cent. 

But what does this have to do with penguin poo?

Well, scientists are interested in tracking these penguin populations, and how they are changing over time. But, given the remote and hostile place that they live, it’s hard to get accurate estimates of penguin numbers, or to easily track their movements.

And this is where the poop comes in.

The diet of an adelie penguin consists of fish, and quite a lot of krill. The large amount of krill that they eat turns their guano a distinctive pink colour, which contrasts quite nicely with the Antarctic snow. So much so that it can actually be seen from space, with penguin colonies showing up as pink patches.

By looking at satellite images, scientists can now more easily track where penguin colonies are. And from the size of the penguin poop patches, they can estimate how many penguins are in a colony.

They’re now looking back at images from the last couple of decades, to see how penguin populations have shifted over that time. This information will help researchers to better understand the natural fluctuations that occur in penguin populations, and to help get a better idea of how these birds are responding to human-made threats such as climate change.

Despite the smell, it turns out that penguin poop is rather useful, after all.

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