Eubalaena japonica 

Scope: Global
Language: English

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Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Mammalia Cetartiodactyla Balaenidae

Scientific Name: Eubalaena japonica (Lacépède, 1818)
Infra-specific Taxa Assessed:
Common Name(s):
English North Pacific Right Whale
Eubalaena glacialis P.L.S. Müller, 1776
Taxonomic Notes: The taxonomy follows the view of the International Whaling Commission (IWC) Scientific Committee (IWC 2004) and the Convention on Migratory Species (CMS), which now recognize Right Whales in the North Atlantic, North Pacific, and Southern Hemisphere as three distinct species in the genus Eubalaena, namely E. glacialis (North Atlantic Right Whale), E. japonica (North Pacific Right Whale), and E. australis (Southern Right Whale), based mainly on the mtDNA phylogenetic analyses of Rosenbaum et al. (2000).

In most of the scientific literature prior to 2000, including previous Red Lists (e.g., Baillie and Groombridge 1996), all Northern Hemisphere Right Whales were treated as the single species E. glacialis.

Rice (1998) classified Right Whales in the North Atlantic, North Pacific and Southern Hemisphere as the single species Balaena glacialis, in the genus Balaena along with B. mysticetus, the Bowhead Whale. While not all cetologists accept that the three Right Whale taxa qualify as full biological species, their clear geographical separation ensures that their treatment as separate taxa for conservation purposes is appropriate.

Assessment Information [top]

Red List Category & Criteria: Endangered D ver 3.1
Year Published: 2018
Date Assessed: 2017-12-19
Assessor(s): Cooke, J.G. & Clapham, P.J.
Reviewer(s): Reeves, R., Brownell Jr., R.L. & Zerbini, A.N.
Contributor(s): Morris, E.
Facilitator/Compiler(s): Lowry, L.
The North Pacific Right Whale has been severely reduced throughout its former range relative to historical levels, and it is especially rare in the eastern North Pacific. Neither the current range-wide population size nor the population trend has yet been satisfactorily quantified. No breeding grounds have been located. The species has to date been listed on the IUCN Red List as Endangered under Criterion D, mature population size below 250 individuals which would correspond to about 400-500 individuals in total. Until all the available data from sighting surveys in the Okhotsk Sea and northwestern North Pacific have been comprehensively analyzed to yield a reliable abundance estimate, the taxon remains listed as Endangered, based on a precautionary application of criterion D, even though it is possible that the number of mature individuals exceeds 250. The Eastern North Pacific Right Whale subpopulation is listed separately as Critically Endangered.
Previously published Red List assessments:

Geographic Range [top]

Range Description:

Catch records from 19th century pelagic whaling and more recent Soviet catches show that Right Whales were widely distributed across coastal and offshore waters of the North Pacific, especially in the Gulf of Alaska south to about 50°N, the southeastern Bering Sea, the northwestern North Pacific, as well as the Okhotsk Sea and Sea of Japan (Townsend 1935, Ivashchenko and Clapham 2012, Josephson et al. 2012, Smith et al. 2012). However, it is apparent that the present range is reduced, especially in the eastern North Pacific. 

Today, Right Whales are known to occur during the summer in the Okhotsk Sea, the northwestern North Pacific (west of 170°W and north of 35°N, including the coast of Kamchatka and the Commander Islands) (Matsuoka et al. 2017, Ovsyanikova et al. 2015), the southeastern Bering Sea, the Aleutian Islands, and the northern Gulf of Alaska (Brownell et al. 2001). During the winter, they occur (or at least occurred historically) southward to the Sea of Japan. There are rare recent records from the Taiwan Strait and the Ogasawara Gunto (Bonin Islands, Japan) in the west, and to Hawaii, California, and Baja California Sur (Mexico) in the east (Brownell et al. 2001).

Historical catch records of Right Whales reported from the central North Pacific by Maury (1852) are now known to be unreliable in terms of species identification (Josephson et al. 2008). Right whales have on rare occasions been recorded in the Hawaiian islands (Rowntree et al. 1980, Salden and Mickelsen 1999); one of those individuals was resighted in the Bering Sea (Kennedy et al. 2012). Whether Hawaii was, or is, a significant part of the species range, remains unresolved. The same uncertainty pertains to Right Whale sightings off Ogasawara, Taiwan, California, and Baja California. In 2015 one Right Whale was found entangled off the south coast of Korea and was released, the first record there since the last catch by whalers in 1974 (Kim et al. 2015). Two separate sightings of Right Whales were made in 2013 off the coast of British Columbia, the first record of this species in Canadian waters in 62 years (Ford et al. 2016).

Unlike Right Whales in the Southern Hemisphere and North Atlantic, neither historical nor extant coastal breeding grounds have been identified for North Pacific Right Whales. Subpopulations on the Asian and American sides of the Pacific are regarded as discrete (Brownell et al. 2001, LeDuc et al. 2012)

Countries occurrence:
Canada (British Columbia); Japan; Korea, Republic of; Mexico (Baja California, Baja California Sur); Russian Federation; Taiwan, Province of China; United States (Alaska, California, Hawaiian Is., Washington)
FAO Marine Fishing Areas:
Pacific – northeast; Pacific – northwest
Additional data:
Continuing decline in area of occupancy (AOO):Unknown
Extreme fluctuations in area of occupancy (AOO):NoEstimated extent of occurrence (EOO) - km2:
Continuing decline in extent of occurrence (EOO):UnknownExtreme fluctuations in extent of occurrence (EOO):No
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:The Right Whale population in the North Pacific is only a small fraction of what it was prior to 19th century whaling. A preliminary estimate of 26,500-37,000 animals taken (including struck and lost) during the period 1839-1909 was given by Scarff (2001), of which 21,000-30,000 were taken during 1840-49 alone. Based on records of encounters of Right Whales by American whaling vessels plotted by Maury (1852) and tabulated by Scarff (1991), areas of highest abundance in summer were the Gulf of Alaska, Aleutian Islands, southern Bering Sea, both coasts of Kamchatka, the Okhotsk Sea, and the northern Sea of Japan. However, the Maury records have been shown to be unreliable in some cases, and the central North Pacific is no longer considered to be an important portion of the historical range of this species (Josephson et al. 2008). Prior to that, there had been catches of Right Whales off both coasts of Japan since at least the 17th century (Omura 1986). There is no evidence of substantial prehistorical catches of Right Whales on the Pacific coast of America. There is pictographic evidence that they were taken off South Korea in neolithic times.

Brownell et al. (2001) calculated that 742 Right Whales had been taken in the North Pacific since the start of modern whaling (1911), of which many were killed illegally by the former USSR. Since then, new records of this whaling have come to light which show that 775 Right Whales were taken by Soviet whalers from 1935 to 1971; most of those catches were illegal, including 517 in the eastern North Pacific (Ivashchenko and Clapham, 2012, Ivashchenko et al. 2017).

Today, Right Whales are known to occur in the Okhotsk Sea between Sakhalin Island and Kamchatka, as well as in the pelagic waters of the northwestern North Pacific. These whales are currently assumed to constitute a single population, but data on movements between the two areas are lacking.

Based on sightings of 28 Right Whales in 2,688 nautical miles of Japanese-Russian cetacean surveys in the Okhotsk Sea in August and September 1989, 1990, and 1992, Miyashita and Kato (1998) derived a preliminary population estimate of 922 whales (95% confidence interval (CI) 404-2,108) using line-transect analysis. Further Japanese surveys were conducted in the Okhotsk Sea in 1999, 2000, 2003, 2009, and 2010 (Matsuoka et al. 2017). A Russian survey in the northern Okhotsk Sea in August and September 2015 encountered five Right Whales (Ovsyanikova et al. 2015). The full set of surveys needs to be analysed before definitive conclusions about abundance and trend can be made.

There have been about a dozen sightings of Right Whales on the east coast of Japan in the 20th century (Brownell et al. 2001). Matsuoka et al. (2017) report a total of 83 Right Whales observed in the northwest Pacific (west of 170°E) during surveys conducted every summer from 1994 to 2016. Most of these were offshore, between 42° and 52°N and 160° and 170°E.  Hakamada and Matsuoka (2016) estimated the abundance of Right Whales in this area at 416 using 2008 data and 1,146 using data from 2011 and 2012. However, these estimates may be positively biased because only those survey years in which Right Whales were seen were used. Matsuoka et al. (2017) summarized all the sightings and effort from all surveys during 1982-2016 by 1 degree squares but noted that further work is needed to obtain a reliable abundance estimate.

In the eastern North Pacific, the few Right Whales observed have usually been alone and in scattered locations. The only exception is an area of the southeastern Bering Sea where small groups of Right Whales were seen in several successive years (LeDuc et al. 2001, Wade et al. 2006). Genetic identification indicated as minimum of 24 individuals but only 6 females (LeDuc et al. 2012). Using photo-identification records from 1998-2013, Wade et al. (2011) estimated a population size of 31 animals for this area, and genetic mark-recapture data produced a similar result. Marques et al. (2011) estimated a total abundance of 25 (95 % CI: 13 – 47) Right Whales in the southeastern Bering Sea (an area of 950,000 km²) from acoustic detections. Three mother-calf pairs were seen in 2004 (Wade et al. 2006).

There have been very few Right Whale sightings in the Gulf of Alaska in recent years despite the fact that the species once occurred commonly across this region. A vessel-based survey off Kodiak in the summer of 2015 failed to observe any Right Whales, although a few acoustic detections were made (Rone et al. 2017). Since 2010, international whale sighting surveys have been conducted each summer in the North Pacific east of 170°E (not including the Bering Sea) under the IWC's POWER programme (IWC 2016). During the surveys from 2010 through 2016, only one Right Whale was seen, in the northwestern Gulf of Alaska. However, the 2017 survey in the eastern Bering Sea recorded 18 right whales (a minimum of 12 individuals; Matsuoka unpublished data).

Current Population Trend:Unknown
Additional data:
Continuing decline of mature individuals:Unknown
Extreme fluctuations:UnknownPopulation severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:Little is known about habitat use by North Pacific Right Whales. By analogy with its congeners (E. glacialis and E. australis) a diet of mainly copepods is presumed. Satellite telemetry and acoustic data indicate the importance of the middle shelf in the southeastern Bering Sea as a foraging habitat, and peak Right Whale call detections and abundance of the copepod Calanus marshallae directly coincide (Baumgartner et al. 2013). Monsarrat et al. (2016) fitted historical North Pacific Right Whale catch data to environmental covariates such as depth, surface temperature, mixing layer depth, and distance offshore, as part of an exercise to characterize Right Whale habitat generally.

The rarity of coastal records in winter in either historical or recent times indicate that the Right Whale's breeding grounds might have been offshore (Clapham et al. 2004); this is in contrast to southern and North Atlantic Right Whales, both of which form inshore breeding concentrations. However, the paucity of historical sightings in low-latitude coastal waters may reflect early depletion of the species on its feeding grounds. There is clearly some northward migration in summer and southward in winter (Clapham et al. 2004), but the location of the wintering grounds is unknown.

Continuing decline in area, extent and/or quality of habitat:Unknown
Generation Length (years):23
Movement patterns:Full Migrant

Use and Trade [top]

Use and Trade: The North Pacific Right Whale is no longer hunted. It was once the target of major commercial whaling.

Threats [top]

Major Threat(s): Hunting of Right Whales in the North Pacific by the Japanese began as early as the late 1500s, and by Europeans and Americans in the 1830s, and by 1900 the population had been reduced to a tiny fraction of its original abundance. Although legally protected by the International Convention for the Regulation of Whaling since 1948 (and by earlier agreements since 1935) illegal hunting continued until 1971, during which Soviet whaling fleets killed 517 Right Whales in the eastern North Pacific, which may have been the bulk of the remaining population there (Ivashchenko and Clapham 2012, Ivashchenko et al. 2017).

There is currently no directed hunting but there have been cases of known and suspected entanglements and ship strikes in the Okhotsk Sea and Kuril Islands, involving at least four whales including one dead (Burdin et al. 2004). Effort is needed to ascertain the frequency of such occurrences, since the low observer effort may mean that most deaths pass unrecorded.

The eastern North Pacific subpopulation appears to be distinct and of extremely small size (only six confirmed females as of 2012) such that its viability may be tenuous. Of the two sightings of Right Whales in 2013 off the coast of British Columbia, the first record of this species in Canadian waters in 62 years, one exhibited a severe but healed injury that was likely from entanglement (Ford et al. 2016). 

Experience in the North Atlantic shows that Right Whales are vulnerable to collisions with ships. The projected increase in shipping through the southeastern Bering Sea as the Arctic Ocean becomes more ice-free is a potential threat to the very small eastern North Pacific subpopulation in terms of ship strikes, as well as noise and pollution. Proposed shipping lanes through the Bering Sea and Bering Strait would cross the area designated under the U.S. Endangered Species Act as Critical Habitat for the Eastern North Pacific Right Whale (IWC 2016). It is known that both ships and whales use Unimak Pass through the eastern Aleutian Islands which, like the Bering Strait, represents a choke point; it is not clear if Right Whales occur in the latter area. Efforts are underway to quantify and address the hazard posed by projected increases in shipping (IWC 2016). Overall, the relative remoteness of the area means that carcasses resulting from ship strikes or other anthropogenic causes could easily go undetected, and even a small number of strikes (e.g., less than one per year) could prevent the recovery of the eastern North Pacific subpopulation.

Conservation Actions [top]

Conservation Actions: North Pacific Right Whales have been legally protected from commercial whaling by international agreements since the 1930s, but this has been fully respected in practice only since the 1970s. The species is in Appendix I of both Convention on International Trade in Endangered Species and the Convention on the Conservation of Migratory Species of Wild Animals. Two areas of Critical Habitat (the southeastern Bering Sea and a small region off eastern Kodiak Island) have been designated for this species under the U.S. Endangered Species Act.

Citation: Cooke, J.G. & Clapham, P.J. 2018. Eubalaena japonica. The IUCN Red List of Threatened Species 2018: e.T41711A50380694. . Downloaded on 19 August 2018.
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