The World Record of largest nest of bird has been achieved by mallee fowl (Leipoa ocellata) from Australia.

It was measured to 4.57 m (15 ft) in height and 10.6 m (35 ft) across, and it has been calculated that a nest site is supposed to involve the mounding of 249 m³ (8,793 ft³) of material weighing 300 tonnes (661,386 lb).

Previous World Records:

The World Record of largest nest of bird was achieved by bald eagles (Haliaeetus leucocephalus) from St Petersburg, Florida, USA. The largest bird’s nest measured 2.9 m (9 ft 6 in) wide and 6 m (20 ft) deep. It was estimated to weigh more than two tonnes (4,409 lb).

The World Record of largest nest of bird was achieved by golden eagle (Aquila chrysaetos) . The largest bird’s nest measured 4.57 m (15 ft).