Translations:Beluga whale/28/en

• Whistles are comparatively continuous, narrowband tonal signals. Their frequency contours may rise, fall, remain level, or change direction several times.
• Pulsed calls are trains of brief broadband pulses. At slow repetition rates, separate impulses may be audible; at high rates, the train can be perceived as a buzz, squawk, or creak. “Burst-pulsed” describes this rapidly repeated region rather than a separate sound-producing organ.
• Combined calls contain simultaneous or closely integrated tonal and pulsed components.
• Echolocation clicks are short, broadband, strongly directional pulses used principally for active sensing. During a rapid sequence they may sound like a buzz to a human listener, but their timing and beam direction differ from many social pulsed calls.