WF#24: A World of Sound

In the ocean, many organisms depend on sound to navigate the world around them. This is very much true for whales.

Whales use sound to communicate. For most baleen whales, song is an essential component of courtship. For the echolocating toothed whales, sound is literally how they perceive the world around them.

Clearly, sound is very important to cetaceans... And it is very important to those of us studying them!

Whale biologists use sound to study whale populations.

How? See whale fact 25 to learn more!

Humpback whales assume this position when they sing. Only the males sing - it is believed that song is sexually selected, either for attracting females, or warning off other males.
Aside from song, whales of all species and sexes vocalize to communicate. the difference is that the songs are specific, stereotyped and repeated, while vocalizations are more random.
Photo credit: indopacificimages.com

Echolocation is like sonar - toothed whales create high-frequency clicks and based on the echos that bounce back, they can determine size, shape, distance and even angular direction! All toothed whales echolocate, but they also vocalize to communicate. Vocalizations have a wider range of patterns, pitches, and duration.
Photo credit: dolphincommunicationproject.org

WF#23: The Return: Omura's Whales

The world's newest baleen whale, Omura's Whale (Balaenoptera omurai) was only just recognized as a distinct species in 2003! Prior to their discovery, they were often confused with Bryde's Whale. It was only recently that we had our first ever siting of a live Omura's Whale off the coast of Madagascar! There is still so much yet to be discovered! Currently, marine biologists are using passive acoustic data to identify and better understand these exciting new members of the mysticeti order!

Omura's Whale

VERSUS

Bryde's Whale
source: WDC

It is easy to see how Omura's whales were confused for Bryde's whales for so long! The main differences are that Omura's whales have a unique asymmetrical pigmentation pattern, where one side of the jaw is significantly lighter than the other. Another distinction is that they have nearly twice as many throat grooves that Brydes whales have.

For more information on Omura's whales, see The Omura's Whale Project, the team that are pioneering these efforts!