Jouvet’s dream realized: Electrophysiological recordings of sleep in penguins exposed to predation on land and at sea

The function of sleep is arguably one of the last great unresolved questions in biology. One approach to tackle this question is to gain a more comprehensive understanding of how animals sleep in challenging environments.
Chinstrap penguins (Pygoscelis antarcticus) face many challenges during the nesting period. In breeding pairs, one partner spends multiple consecutive days foraging at the sea exposed to predation by leopard seals (Hydrurga leptonyx ), while the other has to stay at the nest to protect the eggs from attack by brown skuas (Stercorarius antracticus). The partners alternate between these two behaviors every 5-10 days before hatching . How penguins mitigate the conflict between the simultaneous need to sleep and to remain vigilant for predators is unknown.
Using recently developed data loggers, we recorded multiple continuous days of brain activity, muscle tone, body acceleration, ambient temperature, GPS position, and diving depth in 16 penguins while incubating on land and foraging at sea. We will present the methodology and the electrophysiological and behavioral results obtained in penguins in their natural environment.