The Status of the Great Whales
The Status of the Great Whales
Gentle Giants
Nine of the world's great whales
Current Status of the great whales
|
Species | Status
| Distribution | Total
|
Northern right whale
Eubalaena glacialis
| Endangered. Now the most endangered of the large whales, with no evidence of recovery. Most serious threats: vessel collisions and entanglement in fishing nets.
| Western North Atlantic: probably 300 to 600
Eastern North Atlantic: near extinction
North Pacific: extremely rare, very scattered (perhaps under 500?)
| Probably
under l,000
(There are no
estimates of
pre-whaling
populations)
|
Southern right whale
Eubalaena australis
| Vulnerable. Heavily depleted by commercial whaling, but at least two populations (with nursery areas off Argentina and South Africa) are beginning to recover at an encouraging rate. Most serious threats: entanglement in fishing
nets, habitat destruction such as oil and gas exploitation, illegal hunting.
| Southern Hemisphere | 1,500 - 4,000
(There are
no good
estimates of
pre-whaling
populations)
|
Bowhead whale
Balaena mysticetus
| Vulnerable. Heavily hunted by commercial whalers for whalebone and oil during 18th, 19th, and early 20th centuries, as well as by local people throughout history. Divided into four populations, some evidence of recovery. Most
serious threats: industrial activity including oil and gas exploitation, hunting by lnuit and other native hunters (although the Alaskan hunt is authorized and monitored by the IWC, and this population is thought to be increasing).
| Spitzbergen:initial population about 25,000, now almost extinct, probably below 100
Hudson Bay/Davis Strait: initial population about 12,000, now probably under 500
Okhotsk Sea (NW Pacific): initial population about 8,000, now probably below 500
Bering/Chukchi/Beaufort Seas (around Alaska): initial population about 16,000, now between 6,400 and 9,200 (central estimate: 7,500) (Source: IWC 1988)
| Probably
under 8,500 |
Blue whale
Balaenoptera musculus
| Endangered. Scattered throughout all oceans, but the Northern and Southern Hemisphere populations do not mix since they migrate to tropical waters from their polar summer feeding grounds at different times of the year. The NE P
acific population may be beginning to recover, but the Southern Hemisphere population shows no recovery at all. Most serious threat: illegal whaling.
| North Atlantic (original population estimated at 15,000): now perhaps 1,000 to 2,000
North Pacific (original population estimated at perhaps 10,000): now probably in the range 1,400 to 4,000
Southern Hemisphere (original population around 250,000): now 460 (minimum 210 - maximum 1,000) (Source: IWC 1994)
| Probably
under 5,000 |
Pygmy blue whale
B.m. brevicauda
| A recognized, small subspecies, found further north in the Southern Hemisphere than blue whales. It is not so heavily depleted as it was only exploited after the near-extermination of blue and fin whales.
| Southern Hemisphere | Probably a
few
thousand
remain
|
Fin whale
Balaenoptera physalus
| Vulnerable. Most hunting was stopped in 1975, but some continued in the North Atlantic. There is no evidence of recovery so far. Most serious threat: marine pollution.
| North Atlantic (No pre-exploitation estimates): between 27,700 and 82,000
(Source: IWC 1969-89.) Note: there is considerable uncertainty over this estimate
Mediterranean: a few thousand
Southern Hemisphere (pre-exploitation population estimate is 300,000 to 1 650,000): 24,000
| Probably
about 50,000
to 1 00,000
worldwide
|
Sei whale
Balaenoptera borealis
| Vulnerable. It is especially difficult to estimate their numbers because they are easily confused with Bryde's whales which have an overlapping, but more subtropical, distribution.
| Central North Atlantic: 6,100 - 17,700 (Source: IWC 1989)
Rest of North Atlantic: there are no reliable estimates, although seis are known to be very depleted because hardly any have been seen recently in former whaling grounds. The total is probably under 3,000.
North Pacific: the latest estimate is 13,000, but this dates from 1974 and is not reliable.
Southern Hemisphere: very uncertain estimate: 40,000
| Very roughly
65,000 |
Bryde's whale
Balaenoptera edeni
| Insufficiently known: Only found in tropical and subtropical seas and do not make such long migrations as the other baleen whales. They have been reduced in some areas, especially off Peru, Chile, southern Africa, and Japan. Ma
in threats: depletion of food fish, and illegal hunting (Bryde's are known to be being caught illegally in several areas including the Philippines and Taiwan). Population estimates are very uncertain, partly because they are confused with sei whales. Th
e degree of depletion is unknown, because of undocumented "pirate whaling" in the Atlantic under flags of convenience in the 196Os-1970s.
| | Very roughly
40,000 to 80,000
|
Gray whale
Eschrichtius robustus
| Vulnerable. Of the original three populations, one is extinct in the North Atlantic, one is endangered in the western North Pacific, and one has recovered from very low levels in the eastern North Pacific. It has now recovered
so well, despite the substantial continuing ]WC-permitted aboriginal/subsistence catches on behalf of Siberian communities, that it was removed from the US Endangered Species List in June 1994. Main threats: as shallow water feeders, gray whales stay clo
se to coasts and are vulnerable to human disturbance and entanglement in fishing nets. Their breeding grounds in the lagoon-system of Baja, California are threatened by the expansion of salt-extraction plants on shore.
| Atlantic: extinct
Western North Pacific: perhaps 100 to 200
Eastern North Pacific: 20,400 to 21,800
(Source: IWC 1989)
| Around 22,000 |
Humpback whale
Megaptera novaeangliae
| Vulnerable: Seriously depleted by commercial whaling, but some populations seem to be starting to recover. Several humpback populations are being intensively studied and some 1 0,000 individuals throughout the world have been id
entified using photographs. As the most acrobatic of all the great whales and with fascinating songs, humpbacks are very popular for whale-watching. They feed and breed near coasts, and so are vulnerable to human disturbance.
| Western North Atlantic: 5,500, range 2,890 to 8,120 (Source: IWC 1979-86)
Eastern North Atlantic: original population around 5,000, now very low, possibly a few hundred or less.
North Pacific: original population roughly estimated at 15,000. Estimates for present numbers range from 600 to 2,500
Northern Indian Ocean: perhaps around 500
Southern Hemisphere: around 12,000 (a small fraction of the original population)
| There were
roughly 150,000
before
commercial
whaling, and
perhaps around
20,000 now
|
Minke whale
Balaenoptera
acutorostrata
| Insufficiently known: They have been badly depleted in some parts of the world such as much of the North Atlantic and the western North Pacific, although in other areas including parts of the Southern Ocean they are thought to be
not far below their pre-whaling numbers. They are distributed throughout all oceans.
| Northeastern Atlantic: considerable controversy has surrounded this population estimate, since Norway is currently catching around 300 whales a year under their objection to the moratorium, while the IWC agrees the population is
depleted to below 54% of its original level and should be protected. The latest (1995) unofficial estimate is around 60,000.
Central Atlantic: in the range 21,600 to 31,400 (Source: IWC 1987-89)
West Greenland: in the range 1,790 to 5,950 (Source: IWC 1987-89)
Canadian East coast: no estimate available*
N. Pacific: in the range 12,000 to 48,600 (Source: IWC 1989-90)
S.Hemisphere: estimated in the range 514,000 to 1,1 38,000 (Source: IWC 1982-89)
| In the range
61 0,000 to
1,284,000
|
Sperm whale
Physeter
macrocephalus
| Insufficiently known: There is more uncertainty over the remaining numbers of sperm whales than there is over the other great whales. This is because they remain underwater for long periods, and because they are often found in l
arge groups which makes information from surveys impossible to analyse in the same way as for the other whales. Research has now begun into acoustic survey techniques, but much more remains to be done. The whalers mostly targeted the larger males, so th
at the balance between the sexes has been badly distorted.
| Found in all oceans. More remain in the Northern Hemisphere than in the Southern Hemisphere
| Unknown -
there may
have been
perhaps 3
million
worldwide
before
exploitation,
and possibly
up to 2
million
remain now,
but the total
could be
much lower
|
*Note: these Atlantic divisions are not known to be distinct
biological populations, but are administrative divisions for management
convenience under the old NMP; they are not used in the RMP.
Status categories: From IUCN Red Data Book (1 99
1)
Sources: Almost all estimates based on IWC Scientific
Committee assessments, made at various dates.
WARNING: ALMOST ALL FIGURES ARE VERY APPROXIMATE
In addition, the following are useful sources of information:
* IUCN Red Data Book: Dolphins, Porpoises and Whales
of the World (1991)
* IUCN/SSC Cetaccan Specialist Group, Dolphins, Porpoises and
Whales: 1994-1998 Action Plan for the Conservation of Cetaceans
(1994)
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