crazy as a coot/loon

crazy as a coot/loon

Lunatic behavior. The simile to the water bird dates from the sixteenth century, when John Skelton (Phyllyp Sparowe, 1529) wrote, “the mad coote, with a balde face to toote.” It is not known whether the craziness refers to the bird’s strange behavior in winter, when flocks of coots on a frozen pond sometimes fly wildly at one another, or to the senile behavior of the very old. (See also bald as a coot.) A related ornithological simile is crazy as a loon, probably derived from the weird loud cry of this bird. However, loony for “crazy” comes not from the bird but from lunatic, in turn related to the ancient belief that the phases of the moon (Latin luna) influence human behavior.
See also: coot, crazy, loon