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Publications, Agencies and Staff of the U.S.
Department of Commerce
University of Nebraska - Lincoln Year
Distribution of North Pacific right whales
(Eubalaena japonica) as shown by 19th
and 20th century whaling catch and
sighting records
Phillip J. Clapham∗Caroline Good†Sara E. Quinn‡
Randall R. Reeves∗∗ James E. Scarff†† Robert L. Brownell, Jr.‡‡
∗Large Whale Biology Program, Northeast Fisheries Science Center, 166 Water Street,
Woods Hole, MA 02543, USA, Phillip.Clapham@noaa.gov
†Office of Protected Resources, NOAA Fisheries, 135 East-West Highway, Silver Spring,
MD 20910, USA.
‡Large Whale Biology Program, Northeast Fisheries Science Center, 166 Water Street,
Woods Hole, MA 02543, USA
∗∗Okapi Wildlife Associates, 27 Chandler Lane, Hudson, Quebec J0P 1H0, Canada
††1807 M.L. King Way #A, Berkeley, CA 94709, USA
‡‡Southwest Fisheries Science Center, 1352 Lighthouse Avenue, Pacific Grove, CA 93950,
USA
This paper is posted at DigitalCommons@University of Nebraska - Lincoln.
http://digitalcommons.unl.edu/usdeptcommercepub/95
Distribution of North Pacific right whales (Eubalaena japonica)
as shown by 19
th
and 20
th
century whaling catch and sighting
records
Phillip J. Clapham
*
, Caroline Good
+
, Sara E. Quinn
*
, Randall R. Reeves
#
, James E. Scarff
**
and Robert L.
Brownell, Jr.
++
Contact e-mail: phillip.clapham@noaa.gov
ABSTRACT
North Pacific right whales (Eubalaena japonica) were extensively exploited in the 19
th
century, and their recovery was further retarded
(severely so in the eastern population) by illegal Soviet catches in the 20
th
century, primarily in the 1960s. Monthly plots of right whale
sightings and catches from both the 19
th
and 20
th
centuries are provided, using data summarised by Scarff (1991, from the whale charts of
Matthew Fontaine Maury) and Brownell et al. (2001), respectively. Right whales had an extensive offshore distribution in the 19
th
century,
and were common in areas (such as the Gulf of Alaska and Sea of Japan) where few or no right whales occur today. Seasonal movements
of right whales are apparent in the data, although to some extent these reflect survey and whaling effort. That said, these seasonal
movements indicate a general northward migration in spring from lower latitudes, and major concentrations above 40°N in summer.
Sightings diminished and occurred further south in autumn, and few animals were recorded anywhere in winter. These north-south
migratory movements support the hypothesis of two largely discrete populations of right whales in the eastern and western North Pacific.
Overall, these analyses confirm that the size and range of the right whale population is now considerably diminished in the North Pacific
relative to the situation during the peak period of whaling for this species in the 19
th
century. For management purposes, new surveys are
urgently required to establish the present distribution of this species; existing data suggest that the Bering Sea, the Gulf of Alaska, the
Okhotsk Sea, the Kuril Islands and the coast of Kamchatka are the areas with the greatest likelihood of finding right whales today.
KEYWORDS: NORTH PACIFIC RIGHT WHALE; NORTH PACIFIC; DISTRIBUTION; WHALING – HISTORICAL; WHALING –
MODERN; WHALING – ILLEGAL; MIGRATION; CALVING
INTRODUCTION
North Pacific right whales (Eubalaena japonica) were
intensively hunted from 1835 (Scarff, 1986; 2001). The
species was depleted throughout its range by 1900, when it
had ceased to be a principal target of commercial whaling
(Scarff, 2001). Sporadic catches of right whales for
commercial and scientific purposes were reported in the
early 20
th
century, and it is now known that Soviet whalers
illegally killed at least 508 right whales in the North Pacific
from the 1950s to the early 1970s (Yablokov, 1994;
Doroshenko, 2000). These catches have retarded the
recovery of both the eastern and western North Pacific
populations; in particular, the catches had a devastating
impact on the former (Brownell et al., 2001).
Brownell et al. (2001) reviewed all known 20
th
century
sightings, strandings and catches of North Pacific right
whales. Earlier, Scarff (1986; 1991) examined the
distribution of 19
th
century right whale catches using the
whale charts compiled by Matthew Fontaine Maury (1851;
1852 et seq., 1853). To date, right whale locations contained
in these two large datasets have not been plotted together.
This paper provides monthly plots of North Pacific right
whale sightings and catches in order to investigate seasonal
movements, and to compare the distribution of this species in
the 19
th
and 20
th
centuries.
METHODS AND MATERIALS
Data sources
Nineteenth century
Data on 19
th
century catches and sightings of right whales
from whaling vessels were taken from Scarff’s (1991, table
3) summary of Maury’s whale charts (Maury, 1852). Few
copies of the Maury whale charts are available in public
libraries. A portion of one of these charts can be seen in
Scarff (1986, fig. 2).
It is important to recognise, however, that the Maury data
for the North Pacific have not been validated by direct
examination of his primary sources (whaler logbooks). A
recent study for the North Atlantic comparing data found in
the logbooks with what was depicted on Maury’s 1852 whale
chart has revealed major discrepancies (Reeves, T.D. Smith
and E. Josephson, pers. comm.).
A general description of Maury’s whale charts can be
found in Bannister and Mitchell (1980) and in Scarff (1991).
The data in Maury’s whale charts were shown in 5-degree
squares. For each of the 12 calendar months, Maury’s (1852
et seq.) whale chart displays the data as coloured histograms
reflecting the number of days on which (a) whale ships were
in the square; (b) right whales were seen; and (c) sperm
whales were seen. Scarff (1991) shows numerically the
following data: (a) and (b)/(a), the latter figure described as
the percentage of days on which right whales were seen,
*
Large Whale Biology Program, Northeast Fisheries Science Center, 166 Water Street, Woods Hole, MA 02543, USA.
+
Office of Protected Resources, NOAA Fisheries, 135 East-West Highway, Silver Spring, MD 20910, USA.
#
Okapi Wildlife Associates, 27 Chandler Lane, Hudson, Quebec J0P 1H0, Canada.
**
1807 M.L. King Way #A, Berkeley, CA 94709, USA.
++
Southwest Fisheries Science Center, 1352 Lighthouse Avenue, Pacific Grove, CA 93950, USA.
J. CETACEAN RES. MANAGE. 6(1):1–6, 2004 1
This article is a U.S. government work, and is not subject to copyright in the United States.
which represents a crude index of abundance adjusted for
effort. Thus, the Maury charts provide a useful overview of
where North Pacific right whales were 2and were not 2
found in the first half of the 19
th
century.
Twentieth century
Records of 20
th
century right whale sightings and catches
were taken from the comprehensive review by Brownell et
al. (2001). This dataset includes sightings of 1,965 animals,
as well as 741 catches, from 1900 to 2000; these are
summarised in Table 1. Thirteen strandings of right whales
(12 from the western and one from the eastern North Pacific)
were ignored for the purpose of the present analysis.
Records of right whales from the plots of catch positions
given by C.H. Townsend (1935) were not included. There is
likely to be considerable overlap between the Maury and
Townsend data, but the extent of this problem has yet to be
systematically investigated.
Plots
Monthly plots of the right whale data were created using
ArcView Geographic Information System software. The
data from Scarff (1991) were plotted by 5-degree square as
they appear in his table 3, but corrected for errors. Negative
data (i.e. cases in which search effort was made by whalers
but no right whales were seen) were also plotted. A few
records of whales involving locations at latitudes above
60
o
N were presumed to be of bowhead whales (Balaena
mysticetus) and were ignored. While Scarff (1991) considers
the 50 days of sightings made in the period May to August
between 60° and 65°N and 165° to 170°W to have been of
right whales, a more conservative approach is taken in this
analysis and these are excluded from the plots.
For the 20
th
century data from Brownell et al. (2001), each
record was plotted with a precise position, if available. In
cases in which locations were reported to within a 5 or
10-degree square, the midpoint of that square was used. In
most cases, the exact number of right whales sighted or
killed was available, but in some instances only a range was
given; in these cases, the midpoint of the range was plotted.
In some instances, location information was insufficient to
allow a record to be plotted, and such records were therefore
excluded.
The 20
th
century dataset already included all locations of
right whales reported by Japanese sighting surveys.
However, additional data on the effort involved in most of
those surveys (those from 1964 to 1990) were taken from the
maps provided by Miyashita et al. (1995) in order to show
areas where search effort existed but no sightings of right
whales were made.
RESULTS
Figs 1 to 12 show the reported locations of right whales for
the months of January to December, respectively. Fig. 13
shows additional 20
th
century records for which information
was available for location but not month of sighting. A
general narrative summary of distribution by month (as well
as of areas in which there was search effort but no right
whale sightings) is given in Table 2.
DISCUSSION
Overview
From the data presented here, several observations can be
made. First, the historic distribution of right whales as shown
by the Maury data was often different from that seen in the
20
th
century plots. For example, the historic data show that
CLAPHAM et al.: DISTRIBUTION OF NORTH PACIFIC RIGHT WHALES2
virtually the entire Gulf of Alaska seems to have been used
as a summering ground, together with adjacent waters off the
coasts of British Columbia, the Alaska Peninsula and the
southeastern Bering Sea. Similarly, right whales were once
abundant in the Sea of Japan, an area from which they are
largely absent today.
Overall, the geographic distribution of the species in the
North Pacific was considerably greater in the 19
th
century
than it appears to be in modern times (Scarff, 1991). This is
not surprising since most of the species was removed by
whaling. The remaining animals appear to constitute two
relatively discrete remnant populations (Brownell et al.,
2001). The size of the western population, much of which is
believed to summer in the Okhotsk Sea, is not clear. Data
from Japanese minke whale sighting surveys in the Okhotsk
Sea in 1989, 1990 and 1992 were used to calculate an
estimate of abundance of 922 (CV= 0.433; IWC, 2001,
p.22), although both positive and negative potential biases
were identified in the survey methodology. Noting the wide
confidence intervals associated with this survey, we do not
believe that an abundance in the high hundreds is consistent
with other sighting data on this population (see Brownell et
al., 2001), and suggest that the western population’s size is
likely to be smaller than this.
Figs 1-12. Reported distribution of North Pacific right whales by month from January to December, respectively. Sources are 19
th
century whaling
records (Scarff, 1991, from Maury, 1852), and 20
th
century sighting and whaling catch data (Brownell et al., 2001). Note that because of the
different nature of the source information, 19
th
and 20
th
century records are represented by different measures (percentage of search days on which
right whales were recorded, and number of right whales recorded, respectively). All 20
th
century sightings are indicated by circles of varying size
depending on number of whales seen (see key). Nineteenth century records were summarised by 5-degree square and plotted using different degrees
of shading (see key). Outlined squares with no shading in them indicate squares for which there was known 19
th
century search effort but in which
no right whale sightings were recorded. Hatching indicates squares that were surveyed by Japanese sighting surveys from 1964-1990, but where
no right whale sightings were made (Miyashita et al., 1995). Blank areas with no border or incomplete borders indicate no sightings and no search
effort of any kind in either the Maury data or the Japanese sighting surveys. Fig. 13. Reported distribution of North Pacific right whales in the 20
th
century from records for which there was information on location but not the month of sighting. Data from Brownell et al. (2001).
J. CETACEAN RES. MANAGE. 6(1):1–6, 2004 3
Following catches of 372 right whales by Soviet pelagic
whaling operations (primarily in the 1960s; Doroshenko,
2000), the eastern North Pacific population is believed to
contain fewer (perhaps far fewer) whales than the western
population (LeDuc et al., 2001). Recent surveys,
photo-identification and genetic studies suggest that this
population may number in the tens of animals.
During much of the year, the historic distribution had a
large offshore component in deep water far from the coast.
By contrast, most of the 20
th
century sightings were
relatively close to land, notably off the Aleutian Islands and
in the Bering and Okhotsk Seas. Given the extensive
coverage of Japanese sighting surveys, this recent absence of
right whales in deep water cannot be wholly attributed to
Figs 1-13. Continued.
CLAPHAM et al.: DISTRIBUTION OF NORTH PACIFIC RIGHT WHALES4
lack of effort (see for example May, Fig. 5). Scarff (1991)
noted this offshore component of the Maury data and
suggested that North Pacific right whales may have wintered
and calved far offshore, rather than in the coastal habitats
which many North Atlantic right whales (E. glacialis) and
southern right whales (E. australis) are known to inhabit
during winter (Kraus et al., 1986; Best, 1990; Payne et al.,
1990). This is discussed further below.
Seasonal distribution
Overall movements
Seasonal movements of right whales are apparent in the data
presented here. To some extent these may reflect survey and
whaling effort rather than real migratory movement, and the
apparent movements summarised here must be considered
with that caveat in mind.
There were very few sightings of right whales anywhere in
January and February despite a certain amount of historical
effort, notably in offshore areas (Figs 1 and 2). There are also
few recent sightings of right whales in coastal waters at this
time, despite considerable whalewatching effort in some
locations (e.g. California and Baja California). In March,
most whale sightings appeared in the Maury data in a
latitudinal band between 30 and 40°N, reflecting that in
March over 90% of the whaling effort occurred south of
40°N. Other (though fewer) sightings occur further to the
north; in the Maury data, the area north of 45°N had
consistently high encounter rates even at this time of year,
albeit with small sample sizes.
By April, right whales were widely distributed from 35°N
and had penetrated the Bering Sea; by May and June there
were large numbers of sightings in both the Bering Sea and
the Gulf of Alaska. This pattern continued in July and
August, primarily north of 40°N, in both the Maury and the
20
th
century datasets. In September, the beginnings of a
southward movement were evident; current data suggest that
the last right whales leave the southeastern Bering Sea in
October. By October, right whales were primarily seen in
mid latitudes (30-50°N), and they largely disappear from the
records in November and December.
The movements that can be inferred from the combined
Maury and 20
th
century data are similar to those evident in
the seasonal distribution of North Pacific right whales shown
by Townsend (1935). Townsend’s maps show right whales
abundant in the Gulf of Alaska and adjacent areas (the
Northwest Ground) between May and August, with smaller
numbers in April and September (presumably reflecting
whales moving into and out of the area). Right whales were
also abundant both south and north of the Aleutians in May
and June, as well as in the Bering Sea in summer and early
autumn. Townsend’s maps show concentrations of whales
from the eastern coast of Kamchatka to the offshore waters
of the northwestern North Pacific from May to September,
with additional concentrations in the Okhotsk Sea in spring
and summer. Numerous records in the Sea of Japan in spring,
but far fewer in February and March, probably reflect a
northward migration towards the Sea of Okhotsk and Kuril
Islands; scattered catch positions in February in the Taiwan
Strait and the entrance to the Yellow Sea are indicative of a
northward migration from unknown wintering grounds (see
below). With the exception of a few records at the entrance
to the Yellow Sea in October, there is no indication in the
Townsend data of a parallel southward migration.
Overall, the north-south migratory movements evident in
all three datasets (Maury, Townsend and Brownell et al.)
provide support for the idea that two largely discrete
populations of right whales exist in the eastern and western
North Pacific.
Additional details of the apparent patterns of seasonal
movement are given below.
Eastern North Pacific
Right whales were rarely caught in the coastal whaling
fisheries along the western coast of North America (Scarff,
1986) and so there is less information on the seasonal
movements of this species than in the western regions of the
North Pacific Ocean. As noted above, the plots (notably
those from Maury’s data) show a general movement
northward in spring and south again in autumn. Major
concentrations of summering whales occurred in the Gulf of
Alaska and eastern Bering Sea, and numerous animals were
also recorded in offshore waters for much of the year. The
historical importance of these offshore areas may never be
known, and the persistence of the species there today is
questionable given the great reduction in the size of the
population.
Western North Pacific
Omura (1986) postulated that there were two distinct
populations of right whales in the western North Pacific: the
‘Sea of Japan’ and ‘Pacific’ stocks (taken here to mean
‘sub-populations’). Historical catch data from Japanese
coastal whaling villages indicate that both populations
moved south in autumn and north again in the spring, with
the peak months being September to December and February
to April, respectively. The two putative populations were
kept apart during migration by the Japanese islands, with the
Sea of Japan stock moving along the western coasts, and the
Pacific stock travelling off the eastern coasts of the
archipelago. Omura (1986) suggested that the Pacific
population summered in the Kuril Islands, with some
animals moving further northeast and entering the Bering
Sea. In contrast, he suggested that the feeding grounds for
the Sea of Japan population lay primarily in the Okhotsk Sea,
although he recognised that there was little direct evidence to
support this belief.
As expected, the data presented here support the idea of a
southward movement in the autumn and a return migration
north in spring. Many whales moved into the Okhotsk Sea
during early summer, an event that presumably coincided
with the breakup of ice cover in the area. The Maury data
show significant numbers of right whales entering the
western Bering Sea by June, and remaining there until
September or October, when a general southward movement
is again evident in the sightings. However, it is important to
reiterate that during the entire period of spring to autumn,
right whales were also consistently dispersed in offshore
waters across a broad region of the North Pacific. This
prominent aspect of the right whale’s distribution in the 19
th
century is largely absent in the modern records, further
emphasising the considerable diminution of the species’
range.
Whether there were (or are) two distinct sub-populations
of right whale in the western North Pacific remains unclear.
Catches of right whales by Japanese net whalers at Kawajiri
(a whaling village in Yamaguchi Prefecture on the Sea of
Japan) dropped sharply after 1859, a situation which Omura
(1986) attributes to ‘the operation of American whale ships’.
This may be a rather simplistic interpretation; presumably
the demise of the right whale in the Sea of Japan was due to
a combination of Yankee and coastal whaling, with 20
th
century recovery inhibited to an unknown extent by illegal
Soviet catches on the feeding grounds in the Okhotsk Sea.
J. CETACEAN RES. MANAGE. 6(1):1–6, 2004 5
Wintering/calving grounds
Where North Pacific right whales go in mid-winter, and
where they calve (presumably at this time of year), remains
unknown. For the putative Pacific and Sea of Japan
populations in the western North Pacific, Omura (1986)
suggested that the calving grounds probably lay to the south
of Japan; specifically, he proposed that right whales calved
around or near the Ryukyu Islands (with the implication
being that the two populations may have mixed there). There
is no reliable evidence with respect to the location of coastal
or insular wintering grounds in the eastern North Pacific.
Scarff (1986) speculated that right whales from the Gulf of
Alaska might migrate to calve ‘near the coast of Kamchatka
or further south’. We do not believe that any of the
Kamchatka coast could have been a calving ground; rather,
this area appears to represent a summer feeding habitat, with
sightings made in summer or early autumn.
Indeed, there are few data with which to further examine
this question. In the western North Pacific, the southernmost
sightings from Townsend (1935) are off Taiwan (7 records)
and at around 30°N off the Chinese coast (20 records); all are
from February or March. A few recent sightings have also
been reported from Chichi-jima (Bonin Islands, at 27°N) in
March and April (Brownell et al., 2001). In the eastern North
Pacific, the situation is even more obscure. There, the data
from winter are confined to a handful of 20
th
century
sightings from the western coast of North America, and
some sporadic offshore records in the Maury data. As noted
by Scarff (1986; 1991), there is no evidence from either
historical whaling records or archaeological investigations
of aboriginal hunting peoples that the coastal waters of
western North America ever contained a calving ground for
this species.
Our interpretation of the plots in this regard is that serious
consideration should be given to Scarff’s (1986; 1991)
contention that North Pacific right whales wintered and
calved primarily in offshore, not coastal, waters. Indeed, the
record is conspicuously marked by a paucity of right whale
sightings from any nearshore area in winter, despite the
considerable likelihood of search effort from 19
th
century
(and earlier) coastal whaling communities in both Japan and
North America. In contrast, the apparent historical
abundance of right whales in offshore waters (in both Maury
and Townsend’s data) is too obvious to ignore. In light of
this, Scarff (1986, p.57) concludes:
The recent concentrations of scientific investigations on nearshore
populations of right whales off South America, South Africa, eastern
North America and Australia may have led to an exaggerated view of
the species’ coastal tendencies.
We agree that the offshore distribution of right whales has
been little studied. We suggest that researchers consider the
use of satellite telemetry to locate the many whales that go
‘missing’ in winter, a question which exists even for the
well-studied North Atlantic right whale.
Future work
The analyses presented here provide some direction
regarding future work on this species. In light of the small
size and highly endangered status of both the eastern and
western populations, establishing the present distribution of
right whales, and assessment of anthropogenic threats in the
habitats where they currently exist, should be a top priority
for management. Existing data suggest that the Bering Sea,
Okhotsk Sea, the Kuril Islands and the coast of Kamchatka
are the areas with the greatest likelihood of finding right
whales today. New surveys (including both
photo-identification and biopsy components) of these and
other regions of the North Pacific should be funded and
conducted in the near future.
ACKNOWLEDGMENTS
We are grateful to Richard Merrick and Fred Serchuk for
their reviews of this paper.
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CLAPHAM et al.: DISTRIBUTION OF NORTH PACIFIC RIGHT WHALES6