Sleep regulation in starling birds is highly flexible and sensitive to environmental factors, according to new research published this week in the journal Current Biology.

The study found that starlings sleep five hours less per night during the summer. Compared to winter, the birds take more mid-day naps. During full-moon nights, starlings sleep around two hours less than usual. Researchers hope that this new data on the ways that different species sleep may yield to insights into the regulation and functions of sleep in humans.

The study was conducted by researchers of the UG’s Groningen Institute for Evolutionary Life Sciences, the Avian Sleep Group at the Max Planck Institute for Ornithology in Germany and the Institute of Neuroinformatics, University of Zurich in Switzerland.

In this study, the researchers used miniature electroencephalogram (EEG) data loggers in starlings under semi-natural conditions, meaning the starlings that were housed together in a large outdoor enclosure with natural temperature and light. The results show that the birds displayed strong phenotypical variation in sleep-wake regulation.