Description & Behavior
North Atlantic right whales, Eubalaena glacialis (Müller, 1776), aka Northern right whales, black right whales or Biscayan right whales, are similar in shape to bowheads, being large and stocky, but they are slightly smaller. They are generally the larger of the three right whale species, see southern right whales, Eubalaena australis, with females being slightly larger than males. They are blue-black to light brown in color, with white markings, although some albinos and near-albinos have been recorded. The right whales’ most noticeable feature is the horny growth of callosities on and around the head (primarily near the blowhole, around the rostrum, above the eyes and on the jaw). Callosities are outgrowths of tough skin, and are often used to identify individual whales, as they are unique to each animal similar to fingerprints in humans. The largest of callosities are located on the front-most portion of the head and is referred to as the “bonnet.” Other excrescences are on the upper edge of the lower jaw, behind their blowhole, and above their eyes.
North Atlantic right whales measure between 13.5-18 m, and weigh in the region of 55,000-95,000 kgs. Their baleen is long and narrow, with a maximum length of 3 m and around 400-540 plates per animal.
Right whales are, despite their massive bulk, incredibly active cetaceans, with breaching, lob-tailing and flipper-slapping all relatively common. A particular favorite is ‘sailing’, where the whale hangs vertically upside-down in the water, ‘standing’ on its head, with its tail flukes in the air. They communicate through ‘moans’ and ‘burping’ noises.
The North Atlantic right whale was classified along with closely-related southern right whales, Eubalaena australis under the genus Eubalaena, which literally means ‘right whale’, referring to the belief that these were the ‘right’ whales to kill because they were known to float after dying, making them easy to catch.
World Range & Habitat
Small concentrations of the North Atlantic right whales can be found in the North Pacific (Eubalaena japonica) and the North Atlantic (Eubalaena glacialis). North Atlantic right whales are only found in the Northern Atlantic Ocean from West of Greenland south to Florida and Texas on the western brim and Madeira on the eastern brim.
All species of right whales can be found in polar waters, but in summer they are normally located in temperate and subpolar seas. Right whales often travel in slow moving, small groups of six or less. They have early migrations to the breeding and birthing grounds in the winter months and travel north to the plankton-rich colder feeding waters in the summer. Dives of up to 50 m for 15-20 minutes are common. Calving seems to occur in shallow bays near to the coast, although there is insufficient evidence for this in some areas.
Feeding Behavior (Ecology)
Northern right whales feed by filtering small marine animals out of the water with their baleen plates. The main food is small crustaceans — copepods, krill, and pteropods. They usually feed below the surface, occasionally near the seabed, on concentrations of copepods. Surface feeding has also been observed.
Mating and birthing occurs February to April in the warmer southern waters. Young are born the following spring after a gestation period of a year and measure about 5.5 m at birth. Young nurse for 6-7 months and by weaning have doubled their body size.
Conservation Status & Comments
Longevity: Unknown. All three species of right whales were the first large cetaceans to be commercially hunted by man, possibly as early as the 10th Century. In the nineteenth century alone, over 100,000 whales were slaughtered, and, although having been granted protection in 1935, it is doubtful that this species will ever recover.
Estimated Current Population: <1,000 animals (North Atlantic population <300 animals). The most endangered ‘great’ whale, with full species extinction expected by 2200.
N. Atlantic right whales, Eubalaena glacialis, are classified as Endangered D on the IUCN Red List of Threatened Species
N. Pacific right whales, Eubalaena japonica, are classified as Endangered D on the IUCN Red List of Threatened Species
A taxon is Endangered when the best available evidence indicates that it meets any of the criteria A to E for Endangered (see Section V), and it is therefore considered to be facing a very high risk of extinction in the wild.
LEAST CONCERN (LC)
A taxon is Least Concern when it has been evaluated against the criteria and does not qualify for Critically Endangered, Endangered, Vulnerable or Near Threatened. Widespread and abundant taxa are included in this category.
References & Further Research
North Atlantic Right Whale Catalog – New England Aquarium
Center for Biological Diversity: North Pacific right whale
Ocean Life Institute (WHOI) – Right Whales
Tinker, S. W. 1988. Whales of the World. Bell Press: Honolulu
Jefferson, T. A., S. Leatherwood, and M.A. Webber, FAO species identification guide, Marine mammals of the world, Rome, FAO. 1993. 320 p. 587 figs.
U.S. Fish & Wildlife Service Endangered Species
Research Eubalaena glacialis @
Barcode of Life BioOne Biodiversity Heritage Library CITES Cornell Macaulay Library Encyclopedia of Life (EOL) ESA Online Journals FishBase Florida Museum of Natural History Ichthyology Department GBIF Google Scholar ITIS IUCN RedList (Threatened Status) Marine Species Identification Portal NCBI (PubMed, GenBank, etc.) Ocean Biogeographic Information System PLOS SIRIS Tree of Life Web Project UNEP-WCMC Species Database WoRMS