scholarly journals Conservation status of North Pacific right whales

2020 ◽  
pp. 269-286
Author(s):  
Robert L. Brownell ◽  
Phillip J. Clapham ◽  
Tomio Miyashita ◽  
Toshio Kasuya
Keyword(s):  
North Pacific ◽  
Western North Pacific ◽  
Conservation Status ◽  
Okhotsk Sea ◽  
Right Whale ◽  
The North ◽  
Pacific Population ◽  
Right Whales ◽  
The Impact ◽  
The North Pacific

The North Pacific right whale (Eubalaena japonica) is among the most endangered of all great whales, having been subject to intensivecommercial whaling in the 19th century. All available 20th century records of this species in the North Pacific were reviewed. There hasbeen a total of 1,965 recorded sightings since 1900; of these, 988 came from the western North Pacific, 693 from the eastern North Pacificand 284 had no location specified. Thirteen strandings (all but one from the western North Pacific) were recorded. Known catches forcommercial or scientific purposes totalled 742 (331 in the western North Pacific, 411 in the eastern North Pacific). Most of the reportedSoviet ‘sightings’ in the eastern North Pacific were actually catches, as may be the case for Soviet sightings in the Okhotsk Sea. In addition,the impact of known Soviet illegal catches in the Okhotsk Sea may be reflected in an apparent decline in sightings after the 1960s (althoughthis may be partly explained by low observer effort). Overall, the data support the hypothesis that at least two stocks of right whales existin the North Pacific. Any recovery in the western North Pacific population was compromised by the Soviet catches in the Okhotsk region,although recent sightings suggest that this population is still large enough to sustain reproduction. By contrast, Soviet catches in thenow-smaller eastern North Pacific population have severely reduced its prospects for recovery. Although the prognosis for this populationis poor, a long-term monitoring programme is required to better understand its conservation status and to determine whether it may beaffected by human-related problems that would require mitigation.

Rare sighting of a right whale (Eubalaena glacialis) in Hawaii

1980 ◽  
Vol 58 (2) ◽  
pp. 309-312 ◽  
Author(s):  
V. Rowntree ◽  
J. Darling ◽  
G. Silber ◽  
M. Ferrari
Keyword(s):  
North Pacific ◽  
Individual Recognition ◽  
Eubalaena Glacialis ◽  
Right Whale ◽  
The North ◽  
Pacific Population ◽  
Right Whales ◽  
The North Pacific

The presence of a right whale (Eubalaena glacialis) in the Hawaiian waters on March 25, 1979 was documented by photographs which allow individual recognition. The sighting is significant because right whales have not been reported in these waters since 1851 and because the North Pacific population has been estimated to number only 100–200 individuals even though the killing of right whales has been banned since 1937.

scholarly journals Downstream Development of the Summertime Tropical Cyclone/Submonthly Wave Pattern in the Extratropical North Pacific

2010 ◽  
Vol 23 (8) ◽  
pp. 2223-2229 ◽  
Author(s):  
Ken-Chung Ko ◽  
Huang-Hsiung Hsu
Keyword(s):  
Tropical Cyclone ◽  
North Pacific ◽  
Western North Pacific ◽  
Wave Pattern ◽  
Wave Activity ◽  
Western North America ◽  
Energy Propagation ◽  
The North ◽  
The Impact ◽  
The North Pacific

Abstract The impact of tropical perturbation on the extratropical wave activity in the North Pacific in the submonthly time scale is demonstrated here. Previous studies identified a tropical cyclone (TC)/submonthly wave pattern, which propagated north-northwestward in the Philippine Sea and recurved in the oceanic region between Japan and Taiwan. This study found that, after the arrival of the TC/submonthly wave pattern at the recurving region, the eastward-propagating wave activity in the extratropical North Pacific was significantly enhanced. It is suggested that the TC/submonthly wave pattern, which is originated in the tropical western North Pacific, enhances the eastward energy propagation of Rossby wave–like perturbation in the extratropical North Pacific and may have an impact on the long-range weather predictability in the eastern North Pacific and western North America.

scholarly journals Preliminary estimates of whaling-induced mortality in the 19th century North Pacific right whale (Eubalaena japonicus) fishery, adjusting for struck-but-lost whales and non-American whaling

2020 ◽  
pp. 261-268
Author(s):  
James E. Scarff
Keyword(s):  
19Th Century ◽  
Bering Sea ◽  
North Pacific ◽  
Total Mortality ◽  
Right Whale ◽  
The North ◽  
Right Whales ◽  
Adjustment Factors ◽  
The 19Th Century ◽  
The North Pacific

This study develops preliminary estimates of total whaling-induced mortality of northern right whales in the 19th century North Pacificpelagic whale fishery. Best’s (1987) study of American whaling returns resulted in estimates of the total American catch of 14,480 and15,374 northern right whales during the period 1839-1909. The present study offers adjustment factors to estimate total mortality from thesecatch data. Quantitative data from 14 pelagic expeditions for northern right whales in the North Pacific from 1838-1860 and additionalanecdotal information about struck-but-lost animals is reviewed. On 12 voyages, 327 northern right whales were struck with harpoons, butonly 133 landed. Adjusted for the subsequent recovery of struck whales, this implies a ratio of 2.43 whales struck for each whale eventuallysecured and flensed by whaleships. Data from four voyages show that of 148 northern right whales struck with harpoons, 14 sank beforethey could be processed. From a sample of five voyages, 80 northern right whales were landed and 31 carcasses sank without being secured.During the height of pelagic whaling in the North Pacific, approximately 10% of the fleet was non-American, primarily French. Adjustingrecorded catch estimates for struck-but-lost mortality and non-American whaling yields preliminary estimates of total mortality in thisfishery in the range of 26,500-37,000 animals during the period 1839-1909. In the single decade of 1840-49, between 21,000-30,000northern right whales may have been killed in the North Pacific, Sea of Okhotsk and Bering Sea, representing about 80% of the northernright whales killed in this region during the period 1839-1909.

scholarly journals Natal origin of Namibian grey whale implies new distance record for in-water migration

2021 ◽  
Vol 17 (6) ◽  
pp. 20210136
Author(s):  
A. Rus Hoelzel ◽  
Fatih Sarigol ◽  
Tess Gridley ◽  
Simon H. Elwen
Keyword(s):  
North Pacific ◽  
Western North Pacific ◽  
Water Migration ◽  
Natal Origin ◽  
The North ◽  
Pacific Population ◽  
Conservation Implications ◽  
Grey Whale ◽  
The World ◽  
The North Pacific

We use genomics to identify the natal origin of a grey whale found in the South Atlantic, at least 20 000 km from the species core range (halfway around the world). The data indicate an origin in the North Pacific, possibly from the endangered western North Pacific population, thought to include only approximately 200 individuals. This contributes to our understanding of Atlantic sightings of this species known primarily from the North Pacific, and could have conservation implications if grey whales have the potential for essentially global dispersion. More broadly, documenting and understanding rare extreme migration events have potential implications for the understanding of how a species may be able to respond to global change.

Downstream Development Associated with the Extratropical Transition of Tropical Cyclones over the Western North Pacific

2009 ◽  
Vol 137 (4) ◽  
pp. 1295-1319 ◽  
Author(s):  
Patrick A. Harr ◽  
Jonathan M. Dea
Keyword(s):  
Tropical Cyclone ◽  
Tropical Cyclones ◽  
North Pacific ◽  
Western North Pacific ◽  
High Amplitude ◽  
Extratropical Transition ◽  
The North ◽  
The Impact ◽  
The North Pacific ◽  
Downstream Development

Abstract The movement of a tropical cyclone into the midlatitudes involves interactions among many complex physical processes over a variety of space and time scales. Furthermore, the extratropical transition (ET) of a tropical cyclone may also result in a high-amplitude Rossby wave response that can extend to near-hemispheric scales. After an ET event occurs over the western portion of a Northern Hemisphere ocean basin, the high-amplitude downstream response often forces anomalous midlatitude circulations for periods of days to a week. These circulations may then be related to high-impact weather events far downstream of the forcing by the ET event. In this study, downstream development following ET events over the western North Pacific Ocean is examined. Local eddy kinetic energy analyses are conducted on four cases of North Pacific tropical cyclones of varying characteristics during ET into varying midlatitude flow characteristics during 15 July–30 September 2005. The goal is to examine the impact of each case on downstream development across the North Pacific during a period in which these events might increase the midlatitude cyclogenesis across the North Pacific during a season in which cyclogenesis is typically weak. Four typhoon (TY) cases from the summer of 2005 are chosen to represent the wide spectrum of variability in ET. This includes a case (TY Nabi 14W) that directly resulted in an intense midlatitude cyclone, a case in which a weak midlatitude cyclone resulted (TY Banyan 07W), a case in which the decaying tropical cyclone was absorbed into the midlatitude flow (TY Guchol 12W), and a case (TY Saola 17W) in which the tropical cyclone decayed under the influence of strong vertical wind shear. The variability in downstream response to each ET case is related to specific physical characteristics associated with the evolution of the ET process and the phasing between the poleward-moving tropical cyclone and the midlatitude circulation into which it is moving. A case of downstream development that occurred during September 2005 without an ET event is compared with the four ET cases.

scholarly journals Acoustic detection and satellite-tracking leads to discovery of rare concentration of endangered North Pacific right whales

2006 ◽  
Vol 2 (3) ◽  
pp. 417-419 ◽  
Author(s):  
Paul Wade ◽  
Mads Peter Heide-Jørgensen ◽  
Kim Shelden ◽  
Jay Barlow ◽  
James Carretta ◽  
...  
Keyword(s):  
Bering Sea ◽  
North Pacific ◽  
Right Whale ◽  
The North ◽  
Right Whales ◽  
Time Position ◽  
Eubalaena Japonica ◽  
Bering Sea Shelf ◽  
The North Pacific ◽  
The Bering Sea

The North Pacific right whale, Eubalaena japonica , is one of the most endangered species of whale in the world. On 10 August 2004, two right whales were located in the Bering Sea using headings to right whale calls provided by directional sonobuoys. A satellite-monitored radio tag attached to one of these whales functioned for 40 days. Over the 40-day period, this whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer-shelf where right whales have not been seen in decades. In September, multiple right whales were acoustically located and subsequently sighted by another survey vessel approaching a near-real-time position from the tag. An analysis of photographs confirmed at least 17 individual whales (not including the tagged whales). Genetic analysis of biopsy samples identified 17 individuals: 10 males and 7 females. The discovery of seven females was significant, as only one female had been identified in the past. Genetics also confirmed the presence of at least two calves. Although the future of this population is highly uncertain, the discovery of additional females and calves gives some hope that this most critically endangered of all whale populations may still possess the capacity to recover.

Satellite-Derived Tropical Cyclone Intensity in the North Pacific Ocean Using the Deviation-Angle Variance Technique

2014 ◽  
Vol 29 (3) ◽  
pp. 505-516 ◽  
Author(s):  
Elizabeth A. Ritchie ◽  
Kimberly M. Wood ◽  
Oscar G. Rodríguez-Herrera ◽  
Miguel F. Piñeros ◽  
J. Scott Tyo
Keyword(s):  
Tropical Cyclone ◽  
North Atlantic ◽  
North Pacific ◽  
Western North Pacific ◽  
North Pacific Ocean ◽  
Deviation Angle ◽  
Intensity Estimation ◽  
The North ◽  
The North Atlantic ◽  
The North Pacific

Abstract The deviation-angle variance technique (DAV-T), which was introduced in the North Atlantic basin for tropical cyclone (TC) intensity estimation, is adapted for use in the North Pacific Ocean using the “best-track center” application of the DAV. The adaptations include changes in preprocessing for different data sources [Geostationary Operational Environmental Satellite-East (GOES-E) in the Atlantic, stitched GOES-E–Geostationary Operational Environmental Satellite-West (GOES-W) in the eastern North Pacific, and the Multifunctional Transport Satellite (MTSAT) in the western North Pacific], and retraining the algorithm parameters for different basins. Over the 2007–11 period, DAV-T intensity estimation in the western North Pacific results in a root-mean-square intensity error (RMSE, as measured by the maximum sustained surface winds) of 14.3 kt (1 kt ≈ 0.51 m s−1) when compared to the Joint Typhoon Warning Center best track, utilizing all TCs to train and test the algorithm. The RMSE obtained when testing on an individual year and training with the remaining set lies between 12.9 and 15.1 kt. In the eastern North Pacific the DAV-T produces an RMSE of 13.4 kt utilizing all TCs in 2005–11 when compared with the National Hurricane Center best track. The RMSE for individual years lies between 9.4 and 16.9 kt. The complex environment in the western North Pacific led to an extension to the DAV-T that includes two different radii of computation, producing a parametric surface that relates TC axisymmetry to intensity. The overall RMSE is reduced by an average of 1.3 kt in the western North Pacific and 0.8 kt in the eastern North Pacific. These results for the North Pacific are comparable with previously reported results using the DAV for the North Atlantic basin.

scholarly journals Seasonal Evolution of Aleutian Low Pressure Systems: Implications for the North Pacific Subpolar Circulation*

2009 ◽  
Vol 39 (6) ◽  
pp. 1317-1339 ◽  
Author(s):  
Robert S. Pickart ◽  
Alison M. Macdonald ◽  
G. W. K. Moore ◽  
Ian A. Renfrew ◽  
John E. Walsh ◽  
...  
Keyword(s):  
North Pacific ◽  
Lower Troposphere ◽  
Gulf Of Alaska ◽  
Low Pressure ◽  
Aleutian Low ◽  
The North ◽  
Early Fall ◽  
The Impact ◽  
The North Pacific ◽  
Low Pressure Systems

Abstract The seasonal change in the development of Aleutian low pressure systems from early fall to early winter is analyzed using a combination of meteorological reanalysis fields, satellite sea surface temperature (SST) data, and satellite wind data. The time period of the study is September–December 2002, although results are shown to be representative of the long-term climatology. Characteristics of the storms were documented as they progressed across the North Pacific, including their path, central pressure, deepening rate, and speed of translation. Clear patterns emerged. Storms tended to deepen in two distinct geographical locations—the Gulf of Alaska in early fall and the western North Pacific in late fall. In the Gulf of Alaska, a quasi-permanent “notch” in the SST distribution is argued to be of significance. The signature of the notch is imprinted in the atmosphere, resulting in a region of enhanced cyclonic potential vorticity in the lower troposphere that is conducive for storm development. Later in the season, as winter approaches and the Sea of Okhotsk becomes partially ice covered and cold, the air emanating from the Asian continent leads to enhanced baroclinicity in the region south of Kamchatka. This corresponds to enhanced storm cyclogenesis in that region. Consequently, there is a seasonal westward migration of the dominant lobe of the Aleutian low. The impact of the wind stress curl pattern resulting from these two regions of storm development on the oceanic circulation is investigated using historical hydrography. It is argued that the seasonal bimodal input of cyclonic vorticity from the wind may be partly responsible for the two distinct North Pacific subarctic gyres.

scholarly journals Report on hydrozoans (Cnidaria), excluding Stylasteridae, from the Emperor Seamounts, western North Pacific Ocean

Zootaxa ◽  
2021 ◽  
Vol 4950 (2) ◽  
pp. 201-247
Author(s):  
DALE R. CALDER ◽  
LES WATLING
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
Western North Pacific ◽  
Cold Water ◽  
North Pacific Ocean ◽  
First Record ◽  
Western North Pacific Ocean ◽  
The North ◽  
Seamount Chain ◽  
The North Pacific

Fourteen species of hydroids, collected during August 2019 by ROV SuBastian of the Schmidt Ocean Institute, are reported from the Emperor Seamount chain in the western North Pacific Ocean. Two others, Candelabrum sp. and Eudendrium sp., were observed only on videos taken by the ROV. From collections and video observations, eight species of hydroids were found at Jingū Seamount, three at Yomei, Nintoku, and Annei seamounts, and one at Koko Seamount and Hess Rise. At Suiko and Godaigo seamounts, hydroids were seen in videos but they could not be identified. Latebrahydra schulzei, an endobiotic associate of the hexactinellid sponge Walteria flemmingii Schulze, 1886 from Annei Seamount and Hess Rise, is described as a new genus and species tentatively attributed to Hydractiniidae L. Agassiz, 1862. Another new species, Hydractinia galeai, is described from Jingū Seamount. Among its distinctive characters is a zooid termed a sellectozooid, likely serving in both food capture and defence. Hydroids examined from Yomei, Nintoku, and Jingū seamounts are elements of a cold-water fauna occurring in the North Pacific Boreal Bathyal province, while those of Annei and Koko seamounts, and Hess Rise, are part of the biota of the Central North Pacific Bathyal province. Hydroids identified as Bouillonia sp., from Nintoku Seamount, represent the first record of this predominantly deep water tubulariid genus in the North Pacific Ocean. Bonneviella superba Nutting, 1915, from Jingū Seamount, is reported for the first time outside the Aleutian Islands. Bonneviella cf. gracilis Fraser, 1939, known elsewhere only from Dease Strait in the western Canadian Arctic, was also collected on Jingū. In addition to hydroids, medusae of Ptychogastria polaris Allman, 1878 were observed on videos from Nintoku, Jingū, Annei, and Koko seamounts at depths between 2423–1422 m. An unidentified siphonophore was observed near bottom at 2282 m on Nintoku Seamount. 

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