The timing looks perverse until the chick is considered. By breeding in winter, emperors arrange for chicks to fledge in the southern summer when food is most available and the sea ice edge is closest. The cost falls entirely on the male, who takes the egg onto his feet under a fold of skin and stands through the winter while the female returns to sea to feed.
His fast runs for roughly two months of incubation, on top of the courtship period, adding to something over a hundred days without food in many cases, during which he can lose a large fraction of body mass. Males huddle in dense groups that rotate slowly, so individuals cycle between the sheltered interior and the exposed edge, sharply reducing heat loss for everyone.
The species is also the deepest-diving bird, with recorded dives exceeding 500 metres and durations beyond 20 minutes. Its conservation concern is straightforward: colonies depend on stable fast ice that persists long enough for chicks to fledge.