The underwater hearing threshold of a great cormorant (Phalacrocroax carbo sinensis) was measured at 2 kHz using psychophysical methods. Previous in-air and underwater testing suggests that cormorants have rather poor in-air hearing compared to other birds of similar size (Johansen, 2016). Preliminary data with a new underwater paradigm in a larger pool indicate that cormorants consistently respond to underwater sound and may therefore have special adaptations for underwater hearing.
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