Right Whales

Common Name: Bowhead Whale and Right Whales

Class: Mammalia

Order: Cetacea

Family: Balaenidae

Genus: Eubalaena

Species:  Eubalaena glacialis

Northern right whale Eubalaena glacialis

 

Taxonomy/Description

Right whales belong to the Mammalian Order Cetacea, in the suborder Mysticeti.  All baleen whales belong to the suborder Mysticeti, which is Latin for "mustached whales".  The bowhead whale belongs to the right whale family, Balaenidae.  The right whale's scientific name is Eubalaena glacialis.  Whalers called these whale species the "right" whales because they were the "right" whales to hunt since they did not sink when killed.  Other members of this family include the pygmy right whale and bowhead whale.  Its generic name, Eubalaena, is derived from the Greek eu, meaning "well or true" and balaena, meaning "whale".  The right whale's specific name, glacialis, means "icy", referring to the whale's sub-arctic habitat.  Right whales are identified by there curved mouths, as well as its lacking dorsal fin and ventral white patch.  Large protuberances are located on the heads of right whales.  These patches are roughened callosities, composed of cornified skin and infested with barnacles.  Males usually have larger callosities than females, leading some researchers to hypothesize that males use these bumps for aggressive purposes.  These protuberances are even present at birth.  The large callosity on the tip of the right whale's head is called the "bonnet".  Right whales are 45-55ft in length and 24-25 tons in weight.  Female right whales are usually larger than males of the same age.

Northern right whale Balaena glacialis

Habitat/Diet

Right whales inhabit temperate waters of the all oceans.  However, different populations throughout their range do exist, and some scientists have divided the species into three separate species based on their ranges.  The North Atlantic right whale is named Eubalaena glacialis, and lives in the temperate and sub-arctic waters of the North Atlantic Ocean.  The North Pacific right whale is named Eubalaena japonica, the word japonica referring to the waters surrounding Japan, which are within its North Pacific range.  Lastly, southern right whale is named  Eubalaena australis, australis meaning "southern" in Latin.  Right whales feed primarily on copepods and small crustaceans.  To ingest these surface-dwelling organisms, the right whale strains water at the ocean's surface with its 225-250 baleen plates.  These plates are composed of keratin, the same substance of fingernails and hair.  The ends of baleen are brush-like, preventing the prey from escaping.  The prey remains inside, and is consequently swallowed.

Northern right whale Balaena glacialis

Behavior/Reproduction

Right whales are commonly observed in small groups of 1-3 animals.  Whales of all three populations migrate to cooler waters to feed during the warmer months and warmer waters to breed and calve during the cooler months.  Multiple males will breed with a single female.  Right whales have the largest testicles of all living mammals, but like all other cetaceans, their testicles are internal.  Gestation is about 12-13 months.  Newborn calves range between 10-16ft in length.  Young bowhead whales nurse for 9-12 months.  Calves are weaned at one year.  Right whales are very slow swimmers, but it is not uncommon to observe these animals engaging in acrobatic behaviors, such as breaching.

Northern right whale Balaena glacialis

Conservation

The right whale has been protected since 1937.  However, the northern right whale species were rare during the 18th and 19th centuries due to early whaling.  The southern populations were eventually discovered, and harvested until the early 20th century.  Original population is estimated at 100,000-300,000 individuals worldwide.  Two-thirds were present in the Southern Hemisphere.  The populations of the western Pacific is estimated 100-200 whales, the eastern Pacific having 265 whales, the western Atlantic with 200-300 whales, and the Southern Hemisphere with 3,000 whales.  The population of the eastern Atlantic is nearly extinct.

 

Southern right whale Balaena glacialis

 

Content provided by Canisius College students under the direction of Michael Noonan, PhD.