The Eurasian Tree Sparrow has a bright, sharp call, a "tsipp" a little edgier than that of the House Sparrow, along with a characteristic hard "teck-teck" often heard in flight. The calls are lively and are frequently heard from flocks in the scrub of farmland. There is no real song to speak of; instead a sustained, twittering murmur comes from the sociable flocks. The sharp flight call "teck-teck" is often the first thing to give away that a flock of tree sparrows is on the move.