When the clockwork is wound the music box plays and the glass rods rotate giving the illusion of flowing water. The swan turns its head from side to side and also preens itself. After a few moments the swan notices the swimming fish and bends down to catch and eat one (ornithologically inaccurate, as swans do not eat fish). The swan's head then returns to the upright position and the performance, which has lasted about 40 seconds, is over. To help preserve the mechanism the swan is only operated once each day at 2pm.