Frigate birds power nap [0] so they can stay aloft for weeks, and other birds have been seen to sleep with half their brain at a time [1].
Pretty cool stuff! Have to wonder when this evolved, and whether it could be mimicked.
0: https://www.audubon.org/news/scientists-finally-have-evidenc...
1: https://en.m.wikipedia.org/wiki/Unihemispheric_slow-wave_sle...