The thrushes Turdidae are a rather homogenous group; in fact, all species treated here belong to the genus Turdus. They are well-known for their nocturnal migration and the accompanying NFCs, which can dominate otherwise tranquil nights during the peak of the migration season. Thrush NFCs are essentially the same as their daytime flight calls. Unlike chats and flycatchers, they use flight calls in daytime for short-distance dislocation, when flushed or in prolonged migration flights. Thrushes are arguably the most conspicuous of nocturnal migrants. Anyone with only little experience of nocturnal migration will probably at least have heard the penetrating zeeer of a Redwing T iliacus or the rain of high-pitched tsip calls of Song Thrushes T philomelos on September or October nights. Surprisingly, other species are heard rarely at night (eg, Mistle Thrush T viscivorus), and some also occasionally use alarm calls, perhaps when a congener has come too close.