Great bustard is possibly the largest flying bird - a male reaches up to 16 kg (however, swans and pelicans reach similar sizes). It breeds in southern and central Europe, and across temperate Asia to Far East - however, its population sharply declines and now is found mostly in Spain and Portugal. It was hunted out of existence in Britain by the 1840s, but currently the reintroduction of great bustard to the UK is being carried out.