Berardius bairdii Stejneger,
English: Baird's beaked whale
Spanish: Zifio de Baird, ballena picuda de Baird
French: Baleine à bec de Baird
Berardius bairdii © Wurtz-Artescienza (see "links")
There are few known differences between the two allopatric species
in this genus, the most important being the substantially larger
size of B. bairdii (Kasuya, 2009). The validity of the two
species has long been questioned by some authors, but genetic analysis
of mitochondrial DNA confirmed they are distinct (Dalebout et al.
As in B.arnuxii, the entire body is dark brown but the ventral
side is paler and has irregular white patches. Tooth marks of conspecifics
are numerous on the back, particularly in adult males. Adult size
reaches from 9.1 to 11.1 m. The blowhole is crescent shaped, the
melon is small and has an almost vertical frontal surface, from
which a slender rostrum projects. A pair of large teeth erupt on
the anterior end of the lower jaw at around sexual maturity (Kasuya,
Baird's beaked whale is found in the temperate North Pacific, mainly
in waters over the continental slope. Its range extends in the north
from Cape Navarin (62°N) and the central Sea of Okhotsk (57°N),
where they occur even in shallow waters to the Komandorskiye Ostrova,
Olyutorskiy Zaliv, St. Matthew Island, and the Pribilof Islands
in the Bering Sea, and the northern Gulf of Alaska (Rice, 1998;
In the south, it ranges on the Asian side as far as 34°N, and
to 36°N in the Sea of Japan. The species is not found in the
East China Sea, Yellow Sea and western North Pacific (Kasuya and
Miyashita, 1997). Alleged sightings of B. bairdii across
the central Pacific south as far as 25°N have not been verified
by examination of specimens (they might be Hyperoodon sp.
or Indopacetus sp; Rice, 1998).
Distribution of Berardius
bairdii: across the northern Pacific from Japan, throughout the
Aleutians, and southward along the coast to the southern tip of
California (mod. from Kasuya, 2002, 2009; Taylor et al. 2008; ©
here for large map)
On the American side it ranges south as far as San
Clemente Island (33°N), off Northern Baja California (Rice,
1998; Kasuya, 2002, 2009). It is vagrant to the southwestern Gulf
of California: There have been two records of mass strandings in
the Sea of Cortez near La Paz (24°N), Baja California (Balcomb,
1989; Reyes, 1991 and refs. therein; Urbán-Ramírez
and Jaramillo-Legorreta, 1992).
There may be at least three stocks of Baird's beaked whales in the
western North Pacific: a Sea of Japan stock that summers in the
Sea of Japan and possibly remains isolated there year-round; an
Okhotsk Sea stock distributed in waters near ice floes in that sea,
and a Pacific coastal stock that probably inhabits continental slope
waters between the fronts of the Kuroshio and Oyashio Currents,
north of about 34°N (Balcomb, 1989; Reyes, 1991 and refs. therein).
According to Kasuya and Miyashita (1997) there is no evidence to
alter this three stock hypothesis, which is also adopted by Taylor
et al. (2008). Other possible stocks are found in the Bering Sea
and the eastern North Pacific, in the latter ranging from Alaska
and Vancouver Island possibly to the Sea of Cortez (Balcomb, 1989;
Reyes, 1991 and refs. therein).
The stock hypothesis in the western Pacific is supported by recent
chemical analyses of whale "products". Haraguchi et al.
(2006) found that Baird's beaked whale "products" from
the Pacific Ocean contained significantly higher concentrations
of Mixed halogenated dimethyl bipyrroles (HDBPs) than those from
the Sea of Japan. Furthermore, the geographical distribution of
HDBPs did not resemble those of ubiquitous anthropogenic organochlorines,
such as polychlorinated biphenyl (PCBs).
Furthermore, Kishiro (2007) compared 14 measurements of external
body proportions of 172 Baird's beaked whales caught by small-type
whaling operations off the Pacific coast of Japan, the Sea of Japan
and the Sea of Okhotsk from 1988 to 2004. Canonical discriminant
analysis allowed to discriminate between whales from the Pacific
coast and the Sea of Japan for both males and females, although
some overlap was observed. The flipper size (maximum width and straight
length) of the Pacific coast whales was significantly larger (3.9-8.3%)
than that of the Sea of Japan whales. The canonical variates of
the Sea of Okhotsk whales were located in the middle area between
the Pacific coast and the Sea of Japan and a significant difference
was not observed (however this may have been caused by sampling
errors). Ishiro (2007) concludes that morphological differences
observed between the Pacific coast and the Sea of Japan whales suggest
different stocks occur in these two waters.
3. Population size
There are no recent population estimates or information on trends
in global abundance (Taylor et al. 2008). In the past, sighting
surveys on the whaling grounds indicated a population of several
thousand Baird's beaked whales available to the fishery (Reeves
and Mitchell, 1994). For Japanese waters estimates were 5,029 for
the Pacific coast, 1,260 for the eastern Sea of Japan and 660 for
the southern Okhotsk Sea (IWC 1992). There are an estimated 1,100
Baird's beaked whales in the eastern North Pacific, including about
228 off the US west coast (Ferguson and Barlow, 2001; Barlow, 2003;
both cited in Barlow et al. 2006).
4. Biology and Behaviour
Habitat. Though they may be seen close to shore where deep
water approaches the coast, their primary habitat appear to be over
or near the continental slope and oceanic seamounts (Jefferson et
al. 1993). Baird's beaked whales are found in pelagic, temperate
waters over 1,000 to 3,000 m deep, on the continental slope. Off
the Pacific coast of Japan, these whales have been recorded in waters
ranging between 23°C and 29°C, with a southern limit lying
at the 15°C isotherm at a depth of 100 m. In the northern Okhotsk
Sea the species has been recorded in waters less than 500 m deep,
which could be explained by the availability of prey species in
shallower waters at higher latitudes (Reyes, 1991 and refs. therein).
The prey species found in the stomachs of the whales were almost
identical to those caught in bottom-trawl nets at depths greater
than about 1000m in the western North Pacific, which suggests that
whales reach these depths during foraging dives. Baird's beaked
whales in the western North Pacific migrate to waters of 1,000-3,000m
deep, where demersal fish are abundant, which also reflects these
feeding preferences (Ohizumi et al. 2003).
Minamikawa et al. (2007) confirmed this hypothesis using a depth
and temperature data logger on an individual Baird's beaked whale
off the Pacific coast of Japan. The retrieved data logger recorded
81 dives over approximately 29 h. The maximum recorded depth and
the longest dive duration were 1777 m and 64.4 min, respectively.
Behaviour: They are deep divers, capable of staying down
for up to 67 min, but 85% of dives are shorter than 30 min. During
surface schooling, individuals blow continuously while swimming
slowly and are easily identifiable from shipboard (Kasuya, 2002,
2009). From Japanese whaling data, it appears that males live longer
than females and that females have no post-reproductive stage. There
is a calving peak in March and April (Jefferson et al. 1993).
Schooling: Baird's beaked whales live in larger groups than
any other species of beaked whale, with pods of 5 to 20 whales,
although groups of up to 50 are occasionally seen. They often assemble
in tight groups drifting along at the surface. At such times, snouts
are often seen as animals slide over one another's backs (Jefferson
et al. 1993). Dominance of adult males in the catches off Japan
has been interpreted as an indication of segregation by sex and
age. It was hypothesised that females and calves stay in offshore
waters and that only adult males approach the coast. However, this
is unlikely because of the lack of offshore sightings during summer
fishing seasons. Other speculation referring to higher female mortality
as well as to composition and behaviour of schools need to be verified
with additional studies (Reyes, 1991 and refs. therein).
Food: Prey identification using fish otoliths and cephalopod
beaks reveal that Baird's beaked whales feed primarily on deep-water
gadiform fishes and cephalopods. Off the Pacific coast of Honshu
the whales fed primarily on benthopelagic fishes (81.8%) and only
18.0% on cephalopods. Eight species of fish representing two families,
the codlings (Moridae) and the grenadiers (Macrouridae), collectively
made up 81.3% of the total. Thirty species of cephalopods representing
14 families made up 12.7%. In the southern Sea of Okhotsk, cephalopods
accounted for 87.1% of stomach contents. The families Gonatidae
and Cranchiidae were the predominant cephalopod prey, accounting
for 86.7% of the diet. Gadiform fish accounted for only 12.9% of
the diet. Longfin codling, Laemonema longipes, was the dominant
fish prey in both regions (Walker et al. 2002).
This is supported by Ohizumi et al. (2003) who examined the stomach
contents of Baird's beaked whales caught off the coast of Japan
by small-type coastal whalers. The main prey for these whales was
rat-tails and hakes in the western North Pacific. Pollock and squids
were also important food in the whales collected from the southern
Sea of Okhotsk.
Information gathered from sightings on both sides of the North
Pacific indicate that Baird's beaked whale is present over the continental
slope in summer and autumn months, when water temperatures are highest.
The whales move out from these areas in winter (Reyes, 1991 and
Tomilin (1957); in Balcomb, 1989) reported that in the Sea of Okhotsk
and the Bering sea, Baird's beaked whales arrive between April and
May, and are particularly numerous in summer. He reported they are
not averse to travelling among the ice floes, going as far north
as Cape Navarin (63°N).
Along the Pacific coast of Japan, a migrating population appears
near the Boso Penninsula in May, reaches Hokkaido some time between
July and August, and comes back again to Kinkazan offshore in the
fall and then leaves Japan (Balcomb, 1989 and refs. therein). Kasuya
(1986) noted that the Pacific coast population occurs predominantly
from May to October along the continental slope north of 34°N
in waters 1,000-3,000 m deep. Ohsumi (1983) and Kasuya and Ohsumi
(1984; both in Balcomb, 1989) concluded that there is an apparent
migration away from coastal Japan in winter months. Acording to
Kasuya and Miyashita (1997) they appear in May along the Pacific
coast of Japan, increase in density during summer on the continental
slope (1,000-3,000 m depth) and north of 34°N and apparently
leave in December, although there has been little sighting effort
in December-April in their coastal summering ground. They are not
confirmed in the deeper offshore waters in any season of the year
and their wintering ground is still unknown.
In the eastern North Pacific, along the California coast, Baird's
beaked whales apparently spend the winter and spring months far
offshore, and move in June onto the continental slope off central
and northern California, where peak numbers occur during the months
of September and October. They have been seen or caught off Washington
State between April and October and they were frequently seen by
whalers operating off the west coast of Vancouver Island from May
through October, with their peak occurrence being in August (Balcomb,
1989 and refs. therein).
Direct catches: Until the 1960s and 1970s, Baird's beaked
whales in the eastern North Pacific were taken only by United States
and Canadian whalers (in relatively small numbers). In the western
North Pacific, there has been heavier exploitation by the Soviet
Union and Japan. In the past, Japan's coastal whaling stations took
up to 40 Baird's beaked whales per year. Some Baird's beaked whales
have been caught in Japanese salmon driftnets (Jefferson et al.
1993). In 2001 the industry operated with a quota of 8 for the Sea
of Japan, 2 for the southern Okhotsk Sea and 52 for the Pacific
coasts (Kasuya 2002), and these numbers were slightly raised to
10, 4 and 52, respectively, in 2007 (Kasuya, 2009). Although the
IWC does not control the annual quota of Baird's beaked whales,
it is assumed that the present catch levels over a short period
would not seriously affect the subpopulation, but research is needed
to obtain information that will allow a full assessment of its status
(Taylor et al. 2008).
Incidental catch: Incidental catches have been recorded,
but are generally not common. Some Baird's beaked whales have been
caught in Japanese salmon driftnets (Reeves and Mitchell 1993).
Deliberate culls: None reported (Reyes, 1991; Kasuya, 2009).
Habitat degradation: Heavy boat traffic to and from Tokyo
Bay is said to disturb the migration of Baird's beaked whales off
the Pacific coast of Japan (Reyes, 1991 and refs. therein).
Pollution: The values of PCB/DDE ratios in specimens from
the western North Pacific were found to be relatively lower than
in offshore cetaceans from the same area. Although this led to suggestions
about the restriction of offshore migration in Baird's beaked whales,
the low level of pollutants could be related to the feeding habits
of this deep-diving whale (Subramanian et al. 1988; Reyes, 1991
and refs. therein).
Overfishing: Some squid stocks have been overexploited off
Japan, and fisheries for other squid species are expanding, which
means that conflicts could arise in the future (Reyes, 1991 and
Noise: US government scientists presented a paper at the
2004 IWC meeting that analysed mass strandings of Cuvier's beaked
whale and Baird's beaked whale in Japan from the late 1950s until
2004 (Brownell et al., 2004). The paper reported that there were
11 mass strandings (a total of 51 animals) involving these species,
all of which occurred in Suruga Bay or Sagami Bay on the central
Pacific coast of Honshu. Both of these bays are adjacent to the
command base for operations of the US Navy's Pacific 7th Fleet (Brownell
et al., 2004).
Known and inferred range states:
Canada; Japan; Korea, Democratic People's Republic of; Korea, Republic
of; Mexico; Russian Federation; United States of America (Taylor
et al. 2008).
Berardius bairdii is considered as Data Deficient by IUCN
(Taylor et al. 2008). It is listed in Appendix II of the CMS (unfavourable
conservation status, would benefit from international cooperation;
2009). It is also listed in appendix I&II of CITES.
In particular, the migration between waters of Japan and Russia
occurs in the southern Okhotsk Sea and in waters off the Pacific
coast of Hokkaido and the Kuril Islands. Further studies on stock
identity, distribution, abundance, school structure and behaviour
are needed to resolve some aspects of life history and migrations
(Reyes, 1991 and refs. therein).
· Balcomb KC (1989) Baird's Beaked Whales - Berardius
bairdii Stejneger, 1883; Arnoux Beaked Whale - Berardius
arnuxii Duvernoy, 1851. In: Handbook of Marine Mammals (Ridgway
SH, Harrison SR eds.) Vol. 4: River Dolphins and the Larger Toothed
Whales. Academic Press, London, pp. 261-288.
· Barlow J, Ferguson MC, Perrin WF, Balance L, Gerrodette
T, Joyce G, Macleod CD, Mullin K, Palka DL, Waring G (2006) Abundance
and densities of beaked and bottlenose whales (family Ziphiidae).
J Cetacean Res Manage 7: 263-270
· Brownell Jr RL, Yamada T, Mead JG, van Helden AL (2004).
Mass Strandings of Cuvier's Beaked Whales in Japan: US Naval Acoustic
Link? IWC Scientific Committee Document SC/56/E37, 56th IWC Annual
Meeting, 29 June-10 July 2004, Sorrento, Italy.
· Dalebout ML, Baker CS, Mead JG, Cockroft VG, Yamada TK
(2004) A comprehensive and validated molecular taxonomy of beaked
whales, family Ziphiidae. J Hered 95: 459-473
· Haraguchi K, Hisamichi Y, Endo T (2006) Bioaccumulation
of Naturally Occurring Mixed Halogenated Dimethylbipyrroles in Whale
and Dolphin Products on the Japanese Market. Arch Environ Contam
Toxicol 51: 135-141
· IWC (1992) Report of the sub-committee of small cetaceans.
Rep Int whal Comm 42: 108-119
· Jefferson TA, Leatherwood S, Webber MA (1993) FAO Species
identification guide. Marine mammals of the world. UNEP/FAO, Rome,
· Kasuya T, Miyashita T (1997) Distribution of Baird's beaked
whales off Japan. Rep Int Whal Comm 47: 963-968.
· Kasuya T (1986) Distribution and behavior of Baird's beaked
whales off the Pacific coast of Japan. Sci Rep Whales Res Inst,
Tokyo 37: 61-83.
· Kasuya T (2002) Giant beaked whales. In: Encyclopedia of
marine mammals (Perrin WF, Würsig B, Thewissen JGM, eds.) Academic
Press, San Diego, pp. 519-522.
· Kasuya T (2009) Giant beaked whales. In: Encyclopedia of
marine mammals (Perrin WF, Würsig B, Thewissen JGM, eds.) Academic
Press, San Diego, pp. 498-500.
· Kishiro T (2007) Geographical variations in the external
body proportions of Baird's beaked whales (Berardius bairdii)
off Japan. J Cetacean Res Manag 9: 89-93
· Minamikawa S, Iwasaki T, Kishiro T (2007) Diving behaviour
of a Baird's beaked whale, Berardius bairdii, in the slope
water region of the western North Pacific: first dive records using
a data logger. Fish Oceanogr 16: 573-577
· Ohizumi H, Isoda T, Kishiro T, Kato H (2003) Feeding habits
of Baird's Beaked Whale Berardius bairdii, in the Western
North Pacific and Sea of Okhotsk off Japan. Fish Sci 69: 11-20
· Reeves RR, Mitchell E (1994) Status of Baird's beaked whale,
Berardius bairdii. Can Field Nat 107: 509-523.
· Reyes JC (1991) The conservation of small cetaceans: a
review. Report prepared for the Secretariat of the Convention on
the Conservation of Migratory Species of Wild Animals. UNEP/CMS
· Rice DW (1998) Marine mammals of the world: systematics
and distribution. Society for Marine Mammalogy, Special Publication
Number 4 (Wartzok D, Ed.), Lawrence, KS. USA.
· Subramanian A, Tanabe S, Tatsukawa R (1988) Estimating
some biological parameters of Baird's beaked whales using PCBs and
DDE as tracers. Mar Pollut Bull 284-287.
· Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford,
J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman,
R.L. 2008. Berardius bairdii. In: IUCN 2009. IUCN Red List
of Threatened Species. Version 2009.1. <www.iucnredlist.org>.
· Urban Ramirez J, Jaramillo Legoreta AM (1992) (Second stranding
of Berardius bairdii at La Paz Bay, B.C.S.). Rev Invest Cient
Univ Auton Baja Calif Sur Ser Cienc Mar 1992 vol 3, no 1, 3:85-92.
· Walker WA, Mead JG, Brownell RL Jr (2002) Diets of baird's
beaked whales, Berardius bairdii, in the southern Sea of
Okhotsk and off the Pacific coast of Honshu, Japan. Mar Mamm Sci
© Boris Culik (2010) Odontocetes. The
toothed whales: "Berardius bairdii". UNEP/CMS Secretariat,
© Illustrations by Maurizio Würtz, Artescienza.
© Maps by IUCN.