Wild parrots do not question their bedtime. It arrives when the sun sets and night tucks them in. A full moon might extend a raucous flock’s social time for one night, and certainly the altering seasons in some regions inch the bedtime later or earlier gradually during the year, but when the sun disappears, most wild psittacines say good night.

“Sleep patterns are influenced by sunlight availability (e.g. time of year, latitude),” said Toa Kyle, a biologist with the World Parrot Trust who has studied parrots in the field for the past decade, particularly the great green, or Buffon’s, macaws of Costa Rica and, more recently, some of the macaws, Amazons and conures of Bolivia and Brazil. “Both the areas in South America I work in are relatively close to the equator so sunlight tends to be around 11 to 13 hours per day.”

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