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    North Atlantic Right Whale

Length: 15 – 18 m (50-60’)
Weight: 30 - 80 tons
Population size in Canada:  Atlantic - <350
Population size in World:     <350
Conservation status in Canada:   Endangered (COSEWIC/SARA)
Conservation status in World:      Endangered (IUCN)

Classification
Latin Name: Eubalaena glacialis
Other Names: Biscayan Right whale, Black Right whale
Suborder: Mysticete (Baleen Whale)
Family: Balaenidae

Field Identification

  • up to 60 feet in length
  • large, with very round, robust body
  • two blowholes
  • upper jaw is very arched when viewed from the side and narrow when viewed from the top
  • series of white callosities on head, around blowhole, around eyes and on lower jaw
  • no dorsal fin or ventral grooves
  • very long, narrow black baleen up to 9 feet in length
  • Paddle shaped flippers
  • black body, white belly
  • dark grey, brown or black baleen, ~2m in length
  • large, broad, smooth tail up to 25 feet wide
  • often shows flukes when diving
  • travels at a slow pace
  • V-shaped blow
  • 1-20+ individuals in groups

Description
Right whales are very large and stocky and can be easily identified by their lack of a dorsal fin. Their huge head comprises one third of their length and their mouthline is strongly arched with very long baleen. They are black with varying amounts of white on their underside and have broad, paddle-shaped flippers. Roughened, raised patches of skin, called callosities, cover their head and rostrum. These appear white or cream-coloured because they are covered in large numbers of whale lice (cyamids). Interestingly, these callosities are found in the same places as facial hair in human males. The distinct pattern of callosities on their heads enables researchers to distinguish individuals from one another, allowing researchers to gain important information on the behaviour and life history of these animals. Unlike most other baleen whales, right whales do not have throat grooves. Instead they have very long baleen which can reach lengths of 2.7m (9’).

Life History
Longevity it thought to exceed 70 years. It is not know at what age females become sexually mature, however, the mean age at first birth is 10 years although one female was known to give birth at age 5. Data do not currently exist to estimate the age of sexual maturity of males, however, it appears that only males over the age of 10 get close enough to a female to have an opportunity for mating. Females give birth to a single calf once every three to five years. Calves are born in the winter after a 12 month gestation period. They are usually weaned and independent from their mothers toward the end of their first year.

Distribution
North Atlantic right whales are found mostly in coastal and shelf waters, though they can occasionally be seen offshore. As a result of whaling, their current range and abundance is much reduced from what it once was.  Ranging from Nova Scotia south to the southeastern United States, they are found in the waters off Cape Cod in the spring and move north to their summer feeding and nursery grounds in New England waters, the Bay of Fundy and the Scotian Shelf. Their calving grounds are found off the coasts of Florida and Georgia in the winter. It is not known where most of the population spends their autumn and winter.

Diet
Right whales are plankton feeders and feed mainly on copepods (particularly Calanus finmarchicus) and occasionally krill.

Behaviour
While they may seem slow and cumbersome, the North Atlantic right whale can be quite active - often breaching, lobtailing, flipper slapping and spy-hopping. They are found singly or in very small, unstable groups. However, much larger aggregations occur in good feeding areas. For example, over 150 individuals can be found in the Bay of Fundy during the summer months. Courtship groups can contain anywhere from 3 to 30 individuals, usually comprised of many males trying to maintain a position around a single female. When surfacing, right whales are easily distinguished from other whales in that they have a distinctive v-shaped blow. 

Population size
Less than 350 individuals remain in the North Atlantic right whale population. The eastern North Atlantic population is thought to be nearly extinct as a result of commercial whaling. Their population appears to be in decline.

Threats
One of the most critically endangered mammals in the world, the North Atlantic right whale was the first great whale to be commercially hunted and commercial whaling greatly reduced their population. Their name comes from the fact that they were slow, easy to catch and rich in oil and thus thought to be the “right” whale to kill. Today, the most common threats to the North Atlantic right whale are collisions with vessels and entanglements in fishing gear. Other hypothesized contributing factors for the recent decline in reproduction and the population’s generally slow rate of recovery (or, in recent years, failure to recover at all) include the genetic and demographic effects of small population size, habitat loss and degradation, infectious disease, contaminants, marine biotoxins, an inadequacy of prey resources as a result of changes in ocean climate, and disturbance from tourism.

References

COSEWIC report

Martin, Anthony R. and International Team of Experts. 1990. The Illustrated Encyclopedia of Whales and Dolphins. Portland House, New York, NY.

Reeves, P.A., R.R. Reeves, B.S. Stewart, P.J. Clapham, and J.A. Powell. 2002. Guide to the Marine Mammals of the World. Alfred A. Knopf, New York. 527 pp.

National Audubon Society’s Guide to marine mammals of the world

Encyclopedia of marine mammals

This page was created by Sarah Wong, Dalhousie University, February 2007.