What is a squirrel's nest called?
A drey — or dray — is a nest of a tree squirrel or a flying squirrel. Dreys are usually built of twigs, dry leaves, and grass, and typically assembled in the forks of a tall tree.
A favored site for a drey is a tree crotch about 30 to 45 feet (9.1 to 13.7 m) above ground level. Squirrels may also nest in attics or exterior walls of buildings, where a drey may be regarded as a fire hazard, as some squirrels have a habit of gnawing on electrical cables. At other times, squirrels may inhabit a permanent tree den in the hollow of a trunk or large branch.