North Atlantic Right Whale 

	North Atlantic Right Whale Baleine noire de l'Atlantique Nord Eubalaena glacialis Other names: black right whales, Biscayan right whales, nordkapers

• Round, plump body

Flip Nicklin

• Wide, smooth back, no dorsal fin

• Black back, black belly with the occasional white mark

• White callosities on head

• Strongly arched mouth line and very big lower jaw

• Enormous baleen plates suspended from upper jaw (2.7 m in length)

• Paddle-shaped pectoral fins

• Absence of ventral pleats

When it surfaces: Its sometimes indistinct, V-shaped blow can be as much as five metres high. What sets this species of whale apart from others are the white callosities on its head, its slow swimming speed and the lack of a dorsal fin.

A small population of slow, chubby whales

The North Atlantic right whale is the most endangered great whale in the world having reached the critical population level of an estimated 400 individuals. Several centuries of intensive whaling have pushed this species to the brink. At present, every birth represents a thin hope for its survival. Right whales are round in shape, with large heads adorned with outgrowths. While they do not react very much to the passage of boats, they occasionally perform surprising aerial manoeuvres, and right whale groups are known to be quite energetic on occasion.

Population, range and habitat

In the St. Lawrence: Right whales frequent the coastal, shallow waters of the St. Lawrence from July to September. Although sightings remain exceptional, they have become increasingly regular; a total of 30 individual right whales have been photographed in the St. Lawrence since 1995, mostly in the southern Gulf, off Percé. Certain whales return from year to year; they appear to have adopted this area. An increasing number of right whales have been reported near the Magdalen Islands, in Chaleurs Bay, along the Lower North Shore and in the Estuary since 1998.

Migration: The most visited areas in summer are in Canada and the United States, and include the Bay of Fundy, the Scotian Shelf, the Gulf of Maine and Cape Cod. Right whales migrate south along the East Coast of the United States from October through April when gestating females return to their winter calving grounds off Florida and Georgia.

Worldwide: St. Lawrence right whales belong to the North Atlantic population, which is mainly present in the western North Atlantic; the eastern North Atlantic population has already likely been extirpated. In November of 2007 the North Atlantic Right Whale Consortium used photo-identification to estimate the population at 400 individuals. Right whales gather in regions where oceanographic phenomena, such as thermal fronts, topography and cold-water upwellings, give rise to high concentrations of prey. They also gather in bays, like the Bay of Fundy, that provide some shelter for females with calves. Southern Hemisphere and North Pacific right whales are distinct species.

Behaviour

Feeding: These whales are skim feeders. They feed by moving through the water, either at depth or near the surface, with their mouths agape. They exclusively feed on plankton: mainly copepods and occasionally krill. They sometimes feed in groups.

At the surface: Right whales spend a lot of time at the surface and move very slowly. The fact that they do not react very much to the passage of ships is a major cause of death. Surprisingly, they also execute impressive aerial behaviours. They leap out of the water and land noisily on their backs or bellies and slap the surface with their tails or pectoral fins. Head pointed skyward, they sometimes observe boats: behaviour known as spyhopping. They have also been known to drift head down with their tails in the wind like a sail. Right whales generally fluke up their tails as they dive.

While diving: This species usually dives for six to eight minutes at a time, yet may remain submerged for up to 60 minutes. While most of its prey is within 100 metres of the surface, right whales can dive to depths of 200 metres.

Social behaviour: Predominantly solitary, right whales are also observed in pairs and in small, unstable groups of 10 to 40 at a time. Sexual behaviour, such as touching and rolling over each other, has been noted year round, even when it is not the mating season. Several very energetic males sometimes move and jostle around one or two females at the surface.

Vocal behaviour: Right whales essentially vocalize using low frequencies that are below the 500 Hz threshold. Their vocalizations include growling, squealing, percussive sounds and the odd high-pitched sound in the 1500 to 2000 Hz range. The purpose of these sounds is still not well understood, but likely serve as a form of communication and as part of the social interaction of groups that are active at the surface.

Reproduction

Both genders attain sexual maturity between five and 10 years of age. Mating and calving occur in winter, from November to February. One female may mate successively with several males. The impressive size of male right whale testicles—the largest in the animal world: in excess of 900 kg—suggests that reproduction is heavily based on sperm competition. Gestation lasts approximately12 months. Nursing generally lasts for six to seven months, occasionally up to 18 months. 

About scientific research

The photo-identification of this species is based on the layout of parasite infested skin outgrowths present on the heads of all right whales. This long-term research program is indispensable for determining population estimates. In late 2007, a group of researchers working on this particular population, the North Atlantic Right Whale Consortium, evaluated its recruitment rate as modest. This species is having trouble recovering due to deaths caused by ship strikes and accidental entanglement in fishing gear. Despite extensive conservation measures in Canada and the United States, other causes, including low genetic diversity, disease, contaminants, reproductive problems and declining food sources, may also be inhibiting recovery.

The rightwhale.ca web site, created in 2007, is entirely dedicated to this species. This site contains information on its biology, research and conservation and promotes exchanges between individuals who have a stake in the marine environment. 

North Atlantic right whale "Science and conservation" page.

	Compare