Dolphins, Whales and Porpoises: 2002-2010 Conservation - IUCN

1996 Red List (again, using the 1996 categories
and criteria). The Antarctic stock was listed as
Endangered because its abundance in the early
1990s was estimated to be only in the midhundreds,
with the reasonable possibility that less
than 250 mature individuals were alive at the time.
The North Pacific stock was classified as Lower
Risk/Conservation Dependent, mainly because the
population was estimated at about 2000 in the
early 1990s and evidence suggested an increase off
California. The North Atlantic stock was listed as
Vulnerable because available survey and photoidentification
data suggested a total population of
no more than about 1500, of which less than 1000
would have been mature. Finally, the pygmy blue
whale, centered in the Sub-Antarctic Zone of the
Indian Ocean between 0º and 80ºE, was listed as
Data Deficient because of uncertainty about its
taxonomic status and abundance. Of particular
concern in this assessment was that more than
8000 pygmy blue whales had been taken illegally
by Soviet whalers in the 1960s and 1970s
(Clapham et al. 1999).
Blue whales require continued protection and
close monitoring into the foreseeable future. There does not
appear to be any immediate intention to resume commercial
whaling for them, nor is there any other well-defined threat
from human activities. As noted by Clapham et al. (1999),
however, their nearly exclusive dependence upon euphausiids,
especially krill (Euphausia superba) in the Antarctic,
could make blue whales vulnerable to large-scale changes in
ocean productivity caused, for example, by climate change.
Fin whale, Balaenoptera physalus
Like the blue whale, the fin whale was severely reduced
worldwide by modern commercial whaling. Nearly threequarters
of a million fin whales were reportedly taken in the
Southern Hemisphere alone between 1904 and 1979 (IWC
1995, p.129–130). Their current status is poorly known in
most areas outside the North Atlantic (including the
Mediterranean Sea), where recent studies indicate that there
is a series of geographical “stocks” with limited genetic
exchange (Bérubé et al. 1998), totaling more than 40,000
animals. Fin whales are currently hunted only in Greenland,
but they would likely also become a principal target in
Iceland if whaling were to resume there. Fin whales are
rarely encountered today in those areas of the Southern
Hemisphere where they were taken in large numbers. The
species was classified as Endangered (under the 1996 categories
and criteria) on the basis of an estimated decline of at
least 50% worldwide over the last three generations
(assumed generation time was 20–25 years). As in the case
of blue whales, the greatest decline was in the Southern
Hemisphere, which had the largest original population.
Figure 15. There are definitely two species of Bryde’s whale, but their
taxonomy and nomenclature remain unresolved. The smaller of the
two species, generally called the pygmy Bryde’s whale, occurs in
near-shore waters of southern Asia. The individual shown here was
photographed off Loh Dasami Rinca, Komodo National Park,
Indonesia, April 2000. Genetic analysis of a biopsy from the animal
confirmed its identity as a pygmy Bryde’s whale.
Photo: Benjamin Kahn.
Ship-strikes are a major cause of fin whale mortality (Laist
et al. 2001).
Humpback whale, Megaptera
novaeangliae
Humpback whales have a cosmopolitan distribution that
generally involves long migrations between high-latitude
summer feeding grounds and tropical breeding grounds
(Clapham 2000). Although commercial whaling seriously
depleted all humpback stocks, the species has demonstrated
remarkable resilience and many of those stocks are recovering
(Clapham et al. 1999). As coastal and charismatic
animals, humpbacks are major tourist attractions in some
areas. They are also the subjects of numerous local population
studies (e.g., Steiger and Calambokidis 2000;
Razafindrakoto et al. 2001) as well as basin-scale research
programs (Baker et al. 1998; Smith et al. 1999). Although
they are certainly vulnerable to ship collisions, entanglement
in fishing gear, and disturbance (even serious injury)
from industrial noise, humpbacks seem able to adapt, or at
least tolerate, living in close proximity to a considerable
variety and amount of human activities. They are actively
hunted today only at Bequia, St. Vincent and the
Grenadines, in the eastern Caribbean Sea. With growing
humpback populations, however, pressure to resume commercial
whaling in at least a few areas is likely to mount.
The species was listed as Vulnerable (under the 1996 categories
and criteria) based on the fact that, although most
monitored stocks had shown evidence of fast recovery and
may have increased to more than 50% of their levels three
generations ago (1930s, assuming a 20-year generation
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