Fig. 2
From: Characterizing dual-pulse calls in five Sciaenid species
Oscillograms (above) and spectrograms (below) of dual-pulse calls from five sciaenid species: M. furnieri, C. guatucupa, U. canosai, M. atricauda, and P. courbina. Insets show an expanded view of a single pulse. For M. furnieri and C. guatucupa, each pulse consists of 2–3 cycles, with amplitude peaking in the second cycle and the third cycle is strongly attenuated. In U. canosai, pulses exhibit a gradual increase in amplitude over 5–6 cycles before decreasing. M. atricauda produces pulses of 2–3 cycles, with the second cycle typically showing the highest amplitude. In P. courbina, pulses consist of multiple cycles (12–15), with amplitude also reaching its maximum in the second cycle. Spectrograms were generated using a 1024-point FFT and a Hanning window; darker shading indicates higher amplitude. Fish drawings modified from Menezes & Figueiredo97.
