Largest flock of birds to invade a house

On the evening of 4 May 1998, some neighbours in Pasadena, California, USA, called the local Fire Department to investigate a strange happening in an empty house nearby. The firefighters discovered that more than a thousand swifts (family Apidae) had flown down the chimney, spreading soot everywhere. Some of the swifts were dead, having apparently flown headlong into the walls in panic; it took at least two hours for the firefighters, led by Fire Dept Battalion Chief Joe Nestor (USA), to shoo the rest of the huge flock out of the house, through windows and doors. It is unclear why the swifts flew down the chimney en masse.

Many people have discovered the odd sparrow or blackbird in their house's chimney, but the feathered invasion of a house in Pasadena, California, USA, on the evening of 4 May 1998 resembled a scene from Alfred Hitchcock's film The Birds. Fortunately, the house's owners were not at home, because when neighbours called out the Fire Department to investigate, the firefighters discovered that more than a thousand swifts (family Apidae) had flown down the chimney, spreading soot everywhere. Some of the swifts were dead, having apparently flown headlong into the walls in panic, and it took at least 2 hours for the firefighters, led by Fire Dept Battalion Chief Joe Nestor (USA), to shoo the rest of the huge flock out of the house, through windows and doors. It is unclear why the swifts flew down the chimney en masse.