You’ll be jealous: Chinstrap penguins take up to 10,000 short naps a day

Chinstrap penguins get a total of twelve hours of sleep every day through more than 10,000 extremely short naps. This is evident from a study by an international research team that was published on Thursday evening in the trade journal ‘Science’.

The almost eight million breeding pairs of penguins with the scientific name Pygoscelis antarctica live in Antarctica and on several islands in the South Atlantic Ocean. The female and male take turns incubating. Only in the nest do they have to constantly protect their eggs from birds of prey, the brown skuas. The parent birds also have to defend their nest against other penguins that try to steal nesting material.

This constant tension is the reason for the chinstrap penguin’s unusual sleeping behavior: During breeding, the parent birds accumulate large amounts of sleep through thousands of micro-sleep phases, as the researchers have discovered. They usually nod for more than four seconds at a time, but they still get up to twelve hours of sleep through more than 600 sleep phases per hour – a total of more than 10,000 per day.

The research team, led by Paul-Antoine Libourel from the Neuroscience Research Center in Lyon, recorded the behavior and brain activity of wild chinstrap penguins breeding in a breeding colony on King George Island in Antarctica in December 2019. To measure their brain activity, they equipped 14 birds with custom-made data loggers. There were also video recordings and direct observations.

These bird activities were recorded over eleven days on land and at sea, with the penguins diving to depths of 200 meters. The researchers then examined how nesting at the edge of the colony, where the penguins are exposed to the birds of prey, compared to the center of the colony, affected the penguins’ sleep.

The surprising result: the birds at the edge of the colony sleep ten percent more and one second longer than the birds in the middle of the colony. Disturbance and aggression from other penguins in the colony have a greater impact on sleep than the threat of predators.

In the study, the researchers also showed that penguins can also sleep floating at sea. In general, they spent significantly less time sleeping at sea than on land. After returning to land, the lost sleep was partially recovered, although again only in phases of an average of four seconds. (saw/sda/afp)