We examined the relationship between the spectral quality of the acoustic environment, the courtship sounds and hearing ability of two freshwater gobies, Padogobius martensii and P. nigricans. Sounds of P. nigricans were more intense and had a narrower frequency range than those of P. martensii, yet sound energy peaked at around 100 Hz in both species. Audiograms, obtained with evoked potentials, exhibited thresholds and bandwidth characteristics typical of hearing generalists. Maximum sensitivity occurred at 100 Hz, and thresholds increased sharply at higher frequencies. Hearing abilities in P. martensii were superior to those of P. nigricans in terms of threshold and bandwidth. Species difference in hearing correlated with differences in the amplitude and spectral content of their sounds. Underwater recordings revealed the presence of lowest noise levels at frequencies around 100 Hz, where sound energy in both species was maximal.
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