ðə kˈɔːl ɪz dᵻskɹˈaɪbd æz ˈeɪ "ɹˈætʃɪtlˈaɪk tɹˈɪl", "tʃˈʌklɪŋ kɹˈoʊk", ɔːɹ ˈeɪ "skwˈiːki bəlˈuːnlˈaɪk sˈaʊnd".
The call is described as a "ratchet-like trill", "chuckling croak", or a "squeaky balloon-like sound".