Alcyone
Ἀλκυόνη
A wife who became a kingfisher and stilled the winter sea.
When her husband Ceyx died at sea, she threw herself in after him in grief, and the gods turned them both into kingfishers.
It was believed that for a few days around the winter solstice, while she broods her eggs, the winds die and the sea grows calm.
The phrase halcyon days — a time of peace — comes from here.
SourcesOvid, Metamorphoses