This call is modified to a quieter courtship call on the approach of a female or to a more aggressive version if a male intruder draws near.
ðɪs kˈɔːl ɪz mˈɑːdᵻfˌaɪd tʊ ɐ kwˈaɪəɾɚ kˈoːɹtʃɪp kˈɔːl ɔnðɪ ɐpɹˈoʊtʃ əvə fˈiːmeɪl ɔːɹ tʊ ɐ mˈoːɹ ɐɡɹˈɛsɪv vˈɜːʒən ɪf ɐ mˈeɪl ɪntɹˈuːdɚ dɹˈɔːz nˈɪɹ.