Observing the life-cycle of penguins in the Antarctic is extremely hard. Harsh weather conditions and the remote location of most colonies mean ongoing scientific studies have only been achievable at a handful of sites.

But with populations of many species such as chinstrap (Pygoscelis antarctica) and Adelie (Pygoscelis adeliae) found to be rapidly declining, scientists needed new ways to study penguins and the threats they face.

The hope is that, by developing a non-invasive method, we can track penguins across the whole of the Southern Ocean without researchers needing to disturb them.

To answer the problem, researchers from the University of Oxford, UK, and the Australian Antarctic Division last year set up automatic cameras across Antartica and the subantarctic that recorded every minute of the breeding season in several different colonies.

Nearly 200,000 images were produced that needed to be carefully analysed.

Step forward 1.5 million volunteers who viewed the photographs online. They helped count the penguins, as well as their chicks and eggs, and reported any strange or surprising behaviour in a citizen science project called Penguin Watch.

As well as assessing the health of individual colonies, scientists were able to use this information to make a number of new discoveries.

They found that groups of penguins use their poo (guano) to melt ice earlier than it would naturally disappear, and also spotted a number of sheathbills around the colonies during winter, despite the birds generally being thought to migrate to South America.

Now 500,000 new images of penguins are being released to mark World Penguin Day. The researchers have also continued to install new cameras in the region.

“We hope these new cameras will reveal how often penguins feed their chicks and how long they have to go to sea to feed in different regions," said lead researcher Dr Tom Hart, from the University of Oxford.

“Until now, this has only been possible by putting GPS on penguins. The hope is that, by developing a non-invasive method, we can track penguins across the whole of the Southern Ocean without researchers needing to disturb them.”

The information gathered from the photographs will help scientists to discover what penguins do over the winter, how climate change and human activity affect how they breed and feed, and why some colonies and species are struggling while others thrive.

“The problem is that penguins face different challenges across their range, which could be from climate change, from fisheries or direct human disturbance,” Dr Hart said.

“Timelapse cameras have revolutionised our ability to collect data from a large number of sites simultaneously. Having many more sites monitored and comparing high versus low-fished sites, for example, will enable us to work out which of these threats are causing changes to penguin populations and how we might mitigate them.”

Scientists also hope to use the volunteers’ work to teach a computer how to accurately count penguins and identify individuals of different species.

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