Lesser Known Species

Omura’s Whale

Photo Credit: National Museum of Nature and Science, Tokyo

Common Name: Omura’s Whale

Scientific Name: Balaenoptera omurai

Cetacean Family: Balaenopteridae

Recent Omura’s Whale Article with Video: National Geographic Article

Length as an Adult: Male Omura’s whales are approximately 33 feet (10 meters) and females are about 37.7 feet (11.5 meters). This is one of the few whale species in which the females are larger than the males.

Weight as an Adult: Unknown

Time Spent Nursing: Unknown

Length of pregnancy: Unknown

Range: Specimens of the Omura’s whale have been found in the southern Sea of Japan, the Solomon Sea, the Bohol Sea, and in deep waters near the Cocos Islands. More samples have most likely been found in other areas as well, but classified as Bryde’s Whales (Balaenoptera edeni), before the identification of the Omura’s whale as its own species.

Likelihood of being seen on a whale watch in Massachusetts coastal waters: Highly unlikely

Preferred food: According to Whale and Dolphin Conservation (WDC), the diet of Omura’s whale contains krill and small fish, but according to other sources, the diet is unknown.

Unusual characteristics: Omura’s whale has a defined ridge on its rostrum (front of the head).

Appearance: Omura’s whale has a small slender body with similar coloring as the fin whale with an asymmetrical jaw pattern, dark on the right, light on the left. The dorsal fin is reportedly tall and curved. Still, little is known about the Omura’s whale, including the physical appearance.

General information: Omura’s whale is a very recently described species. It had originally been mistaken as a dwarf version of Bryde’s whale, until 2003. Nine specimens have been confirmed to be Omura’s whales, which makes it difficult to gather information on the species and is therefore “data deficient” according to IUCN. It is one of the least known whales in the world.

Unusual habits: Not enough is known about this species to report on this aspect of its life.

Population Status: According to the IUCN, there is a population estimate of 1,800 in the Solomon Sea. This figure is unreliable as there are few samples to provide evidence of the estimate. The global population is unknown.

Threats: Possible captures during past and current whaling operations.

References:

IUCN (International Union for Conservation of Nature) List of Threatened Species http://www.iucnredlist.org/details/136623/0

WDC (Whale and Dolphin Conservation) http://us.whales.org/species-guide/omuras-whale

Prepared by: Annika Schmidt

Last modified: August 18, 2016