Beluga whales have a very acute hearing, especially at higher frequencies, and can hear as well at 300m underwater as they can above water.
Beluga whales have a very acute hearing, especially at higher frequencies. They hear a wide range of frequencies with the best sensitivity in the ultrasonic range around 30 or 35 kilohertz and sensitivity extending to at least 130 kilohertz. For comparison, the peak range of human hearing is between .02 and 20 kilohertz. Studies have shown that belugas can hear as well in water as deep as 300 meters, (984 feet), as they can at the surface.
The small external ears of belugas may be useful for hearing low-frequency sounds, however, most vocalizations made by odontocetes are above 30 kilohertz, emphasizing the great importance of the lower jaw pathway for sound reception. Belugas have good in frequency tuning and are able to detect echolocation signals in high levels of background noise and reverberation.
A number of studies have assessed the potential impacts of environmental sound on belugas. These have involved determination of when the level of a particular sound impacted hearing by producing a temporary rise in hearing threshold.
Beluga whales seem to have a parasite called Pharurus pallasii, thought to infect the hearing organs. However, it is not known if this parasite is harmful to the beluga.
Sources: (AMMPA, 2014, 2017; Lentfer, 1988; Moore, Pawloski, & Dankiewicz, 1995; Ridgway, et al, 2001; Schlundt, Finneran, Carder, & Ridgway, 2000; Suydam, Lowry, Frost, O’Corry-Crowe, & Pikok, 2001; Williams, 2002)
Image: Sheila Sund