North Pacific Right Whale (Eubalaena japonica)
Status | Taxonomy | Species Description | Habitat | Distribution |Population Trends | Threats | Conservation Efforts | Regulatory Overview |
Key Documents | More Info | Photos
Status
ESA Endangered - throughout its range
MMPA Depleted - throughout its range
Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Balaenidae
Genus: Eubalaena
Species: japonica
The North Atlantic right whale (Eubalaena glacialis) and southern right whale (Eubalaena australis) are other species of right whale.
Species Description
Right whales are large baleen whales. Adults are generally between 45 and 55 feet (13.7-16.7 m) in length and can weigh up to 70 tons (140,000 lbs; 63,502 kg). Females are larger than males. Calves are 13-15 feet (3.9-4.6 m) in length 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.
Habitat
Most known right whale nursery areas are in shallow, coastal waters. The International Whaling Commission 
has identified four categories of right whale habitats:
- Feeding - areas with copepod and krill densities that routinely elicit feeding behavior and are visited seasonally
- Calving - areas routinely used for calving and neonatal nursing
- Nursery - aggregation area(s) where nursing females feed and suckle
- Breeding - locations where mating behavior leading to conception occurs; breeding areas are not known for any population
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.
 North Pacific Right Whale Critical Habitat (AK) (click for larger view PDF) |
Critical Habitat
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, NMFS was 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]).
Distribution
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.
Recently, there have been few sightings of right whales 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.
Population Trends
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.
In general, there are no data on trends in abundance for either the eastern or western population. For the western North Pacific, sighting survey estimates for the summer feeding ground indicate an abundance of around 900 in the Sea of Okhotsk. It is clear that this population is significantly larger than that in the eastern North Pacific. Over the past forty years, most sightings in the eastern North Pacific have been of single whales. However, during the last few years, small groups of right whales have been sighted. This is encouraging but there has been only one confirmed sighting of calves in the 20th century. Further, the North Pacific animals are known to have been subjected to large illegal Soviet catches in the early 1960s.
Threats
In the North Pacific, ship strikes and entanglements may pose a threat to right whales. However, because of their rare occurrence and scattered distribution, it is impossible to assess the threat of ship strikes or entanglement to North Pacific right whales at this time. Thus, the estimated annual rate of human-caused mortality and serious injury appears minimal. The reasons for the apparent lack of recovery for right whales in this region are unknown.
Conservation Efforts
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, NMFS 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]).
Recovery Plan
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, NMFS 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 was 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
NMFS revised the plan in 2005 for the North Atlantic right whale. A separate recovery plan is being developed for the North Pacific right whale population.
Regulatory Overview
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, NMFS 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, NMFS was 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).
Key Documents
(All documents are in PDF format.)
| Title | Federal Register | Date |
|---|---|---|
| Critical Habitat Designation | 73 FR 19000 | 04/08/2008 |
|
71 FR 38277 | 07/06/2006 |
| ESA Listing Rule to List North Atlantic and North Pacific Right Whales as Separate Species (previously listed as "Northern Right Whale") | 73 FR 12024 | 03/06/2008 |
| Status Review: Right Whales in the North Atlantic and North Pacific Oceans | n/a | 12/2006 |
| ESA Listing Rule (Northern Right Whales) | 35 FR 18319 | 12/02/1970 |
| Stock Assessment Reports | n/a | various |
- Kids' Times: Right Whale [pdf]
- NMFS National Marine Mammal Laboratory North Pacific Right Whale Information
- Environmental Impact Statement (EIS) on Right Whale Scientific Research
- Best, PB, Bannister, JL, Brownell Jr, RL and Donovan, GP, eds. 2001 "Right Whales: Worldwide Status." The Journal of Cetacean Research and Management (Special Issue): 2. Available from the International Whaling Commission
