The common quail (Coturnix coturnix) is Europe's only migratory gamebird, and the flat, hedgerow-lined farmland of the Dutch polders offers exactly the kind of open cereal and grass fields it favors during its brief summer stay. It is far more often heard than seen — a small, secretive bird that spends nearly its entire life hidden in standing crops.
Mottled brown and buff overall, with pale streaking that breaks up its outline against stubble and grass, the quail is barely larger than a starling and built low and round for a life spent entirely on the ground. Males show a faint dark throat pattern in breeding plumage, but plumage detail rarely matters in the field — this is a bird identified by ear, not by eye.
The male's territorial call, a distinctive three-note "wet-my-lips," carries remarkably far across open fields at dusk and dawn and is the primary way the species is ever detected. Actually flushing one from cover is uncommon and usually accidental — they prefer to run rather than fly, and only take to the air as an absolute last resort.
A bird defined by its voice rather than its appearance — most people who've "seen" a quail have really only ever heard one.