 The main call of the American white ibis is a honking sound , transcribed as urnk , urnk , or hunk , hunk . The call is used in flight , courtship or when disturbed . Birds also utter a muted huu @-@ huu @-@ huu call while foraging , and make a squealing call in courtship . Young in the nest give a high @-@ pitched zziu as a begging call . 
