Much energy is used in the vocalization and it takes a toll on the territory holder who may be displaced by a fitter rival if he tires.
mˈʌtʃ ˈɛnɚdʒi ɪz jˈuːzd ɪnðə vˌoʊkəlᵻzˈeɪʃən ænd ɪt tˈeɪks ɐ tˈoʊl ɔnðə tˈɛɹɪtˌoːɹi hˈoʊldɚ hˌuː mˈeɪ biː dɪsplˈeɪst baɪ ɐ fˈɪɾɚ ɹˈaɪvəl ɪf hiː tˈaɪɚz.