Fig. 1. The advertisement call of male Gulf toadfish is termed a boatwhistle. Shown here is a spectrogram (top) and oscillogram (bottom) of a representative boatwhistle recorded in May, 2002 at 28.6°C. A single call includes a series of non-harmonic `grunts' that are followed by a multi-harmonic, tonal `hoot'. Adapted with permission from Remage-Healey and Bass (Remage-Healey and Bass, 2005).