They are attracted there by the calling of the first male to find a suitable place, perhaps a pool that forms in the same place each rainy season.
ðeɪ ɑːɹ ɐtɹˈæktᵻd ðɛɹ baɪ ðə kˈɔːlɪŋ ʌvðə fˈɜːst mˈeɪl tə fˈaɪnd ɐ sˈuːɾəbəl plˈeɪs, pɚhˈæps ɐ pˈuːl ðæt fˈɔːɹmz ɪnðə sˈeɪm plˈeɪs ˈiːtʃ ɹˈeɪni sˈiːzən.