aggressive alert Australian bird common gymnorhina tibicen insectivore lookout Magpie protective sharp sharp eyed swoop swooping territorial watchful watching beak black-and-white gymnorhina-tibicen maggie mottled nesting nesting-material plumage scavenging scrounging sharp-eyed adolescent-bird clawed claws dark feeding grass grassed area gray grey adolescent bird black and white Australian-magpie boy bright-clothing brother caps children close competition curious enjoyment fearless friendly fun grassed-area headgear kids park picnic picnic-blanket relaxation relaxing seated shade shadows sister sitting sunlight sunshine visited visiting visitor wildlife