Right whales are large baleen whales. Adults are generally 45-55 feet (13.7-16.7 m) in length and can weigh up to 70 tons (140,000 lbs; 63,500 kg). Females are larger than males. Calves are 13-15 feet (4-4.5 m) at birth.
Distinguishing features for right whales include a stocky body, generally black coloration (although some individuals have white patches on their undersides), lack of a dorsal fin, a large head (about 1/4 of the body length), strongly bowed margin of the lower lip, and callosities (raised patches of roughened skin) on the head region. Two rows of long (up to eight feet in length) dark baleen plates hang from the upper jaw, with about 225 plates on each side. The tail is broad, deeply notched, and all black with a smooth trailing edge.
Females give birth to their first calf at an average age of 9-10 years. Gestation lasts approximately 1 year. Calves are usually weaned toward the end of their first year.
Using cross-sections of teeth is one way to age mammals. However, right whales have no teeth. Therefore, ear bones and, in some cases, eye lenses can be used to estimate age in right whales after they have died. It is believed that right whales live at least 50 years, but there are few data on the longevity of right whales. There are indications that closely related species may live over 100 years.
Right whales feed from spring to fall, and also in winter in certain areas. The primary food sources are zooplankton, including copepods, euphausiids, and cyprids. Unlike other baleen whales, right whales are skimmers: they feed by removing prey from the water using baleen while moving with their mouth open through a patch of zooplankton.
|up to 70 tons (140,000 lbs; 63,500 kg)|
|45-55 feet (13.7-16.7 m);
calves are 13-15 feet (4-4.5 m) at birth
|stocky black body, with no dorsal fin, and callosities (raised patches of rough skin) on the head region|
|about 50 years, but there are few data on the longevity of right whales. There are indications that closely related species may live over 100 years.|
|zooplankton, including copepods, euphausiids, and cyprids|
|Unlike other baleen whales, right whales are skimmers: they feed by removing prey from the water using baleen while moving with their mouth open through a patch of zooplankton.|
Most known right whale nursery areas are in shallow, coastal waters.
Right whales have occurred historically in all the world’s oceans from temperate to subpolar latitudes. They primarily occur in coastal or shelf waters, although movements over deep waters are known. For much of the year, their distribution is strongly correlated to the distribution of their prey. During winter, right whales occur in lower latitudes and coastal waters where calving takes place. However, the whereabouts of much of the population during winter remains unknown. Right whales migrate to higher latitudes during spring and summer.
In April 2008, because the North Pacific right whale was listed as a separate, endangered species (the “northern right whale”), and because this was a newly listed entity, we were required to designate critical habitat for the “North Pacific right whale.” The same two areas, within the Gulf of Alaska and within the Bering Sea, that were previously designated as critical habitat in 2006 (71 FR 38277 [pdf]) for the “northern right whale” are now designated as critical habitat for the “North Pacific right whale” (73 FR 19000 [pdf]).
North Pacific right whales inhabit the Pacific Ocean, particularly between 20° and 60° latitude.
Before commercial whalers heavily exploited right whales in the North Pacific, concentrations were found in the Gulf of Alaska, eastern Aleutian Islands, south central Bering Sea, Sea of Okhotsk, and Sea of Japan.
Few sightings of right whales occur in the central North Pacific and Bering Sea. Sightings have been reported as far south as central Baja California in the eastern North Pacific, as far south as Hawaii in the central North Pacific, and as far north as the sub-Arctic waters of the Bering Sea and sea of Okhotsk in the summer. Since 1996, right whales have been consistently observed in Bristol Bay, southeastern Bering Sea, during the summer months.
Migratory patterns of the North Pacific right whale are unknown, although it is thought the whales spend the summer on high-latitude feeding grounds and migrate to more temperate waters during the winter.
There are no reliable estimates of current abundance or trends for right whales in the North Pacific. However, the pre-exploitation size of this stock exceeded 11,000 animals. The most recent stock assessment reports with population estimates are available on our website. In general, there are no data on trends in abundance. Most sightings in the eastern North Pacific have been of single whales, though small groups have been sighted.
Because of their rare occurrence and scattered distribution, it is nearly impossible to assess all the threats to this species, but possible threats include:
- ship strikes
The reasons for the apparent lack of recovery for right whales in this region are unknown.
Right whales were first protected by the 1931 Convention for the Regulation of Whaling, which took effect in 1935. However, neither Japan nor the Soviet Union signed this agreement, so they were theoretically free to kill right whales.
In 1949, the International Convention for the Regulation of Whaling protected right whales from commercial whaling. In U.S. waters, right whales were determined as in danger of extinction in all or a significant portion of their range due to commercial over-utilization, and the “northern right whale” was listed as endangered under the Endangered Species Conservation Act in June 1970, the precursor to the ESA. The species was subsequently listed as endangered under the ESA in 1973. In the same year, the species was designated as depleted under the Marine Mammal Protection Act (MMPA). In 2008, we listed the endangered northern right whale (Eubalaena spp.) as two separate, endangered species, North Pacific right whale (E. japonica) and North Atlantic right whale (E. glacialis) [pdf] (73 FR 12024 [pdf]).
We published the Draft North Pacific Right Whale Recovery Plan in January 2013.
Northern Right Whale Recovery Plan (1991):
The Northern Right Whale Recovery Team was appointed in July 1987. A Draft Recovery Plan for the Northern Right Whale (including both the North Atlantic and North Pacific right whales) was distributed for public comment in February 1990. Comments were received from Federal, state and local governments, conservation organizations, and private individuals. Appropriate comments were incorporated into the plan. In December 1991, we approved the Final Recovery Plan for the Northern Right Whale (including both the North Atlantic and North Pacific right whales). It identified known and potential factors affecting the right whale and recommended actions to reduce or eliminate impacts to the species.
The ultimate goal of the plan is to recover the species, with an interim goal of down-listing their status from “endangered” to “threatened.”
The major actions recommended in the plan are:
- Reduce or eliminate injury or mortality caused by ship collision
- Reduce or eliminate injury and mortality caused by fisheries and fishing gear
- Protect habitats essential to the survival and recovery of the species
- Minimize effects of vessel disturbance
- Continue international ban on hunting and other directed take
- Monitor the population size and trends in abundance of the species
- Maximize efforts to free entangled or stranded right whales and acquire scientific information from dead specimens
The North Pacific right whale (Eubalaena japonica) has been listed as endangered under the ESA since 1973 when it was listed as the “northern right whale.” It was originally listed as endangered under the Endangered Species Conservation Act, the precursor to the ESA, in June 1970. The species is also designated as depleted under the Marine Mammal Protection Act (MMPA). In 2008, we listed the endangered northern right whale (Eubalaena spp.) as two separate, endangered species: North Pacific right whale (E. japonica) and North Atlantic right whale (E. glacialis) [pdf] (73 FR 12024 [pdf]).
In April 2008, because the North Pacific right whale was listed as a separate, endangered species (the “northern right whale”), and because this was a newly listed entity, we were required to designate critical habitat for the “North Pacific right whale.” The same two areas, within the Gulf of Alaska and within the Bering Sea, that were previously designated as critical habitat (71 FR 38277 [pdf], July 6, 2006) for the northern right whale are now designated as critical habitat for the North Pacific right whale (73 FR 19000 [pdf], April 8, 2008).
- Right whales are the rarest of all large whale species and among the rarest of all marine mammal species.