 The noisy miner colony unites to mob inter @-@ specific intruders and predators . The noisy miner will approach the threat closely and point , expose eye patches , and often bill @-@ snap . Five to fifteen birds will fly around the intruder , some birds diving at it and either pulling away or striking the intruder . The mobbing continues until the intruder remains still , as with a tawny frogmouth ( Podargus strigoides ) , or it leaves the area . Mobbing of snakes and goannas is particularly intense , and most species of bird , even non @-@ predators , entering the territory are immediately chased . The noisy miner has been recorded attacking an Australian owlet @-@ nightjar ( Aegotheles cristatus ) during the day , grebes , herons , ducks and cormorants on lakes at the edge of territories , crested pigeons ( Ocyphaps lophotes ) , pardalotes , and rosellas . Non @-@ predatory mammals such as bats , cattle , sheep , and wallabies are also attacked , though less vigorously than birds . 
