 There are three types of foraging behaviour observed in the common starling . " <unk> " involves the bird <unk> its beak into the ground randomly and <unk> until an insect has been found , and is often accompanied by bill <unk> where the bird opens its beak in the soil to <unk> a hole . This behaviour , first described by Konrad Lorenz and given the German term <unk> , is also used to create and widen holes in plastic garbage bags . It takes time for young common starlings to perfect this technique , and because of this the diet of young birds will often contain fewer insects . " <unk> " is the capture of flying insects directly from the air , and " <unk> " is the less common technique of striking forward to catch a moving invertebrate on the ground . <unk> are caught by pulling from soil . Common starlings that have periods without access to food , or have a reduction in the hours of light available for feeding , compensate by increasing their body mass by the deposition of fat . 
