THE
ENVIRONMENT AND WHALE STOCKS
With increasing awareness that whales
should not be considered apart from the marine environment
which they inhabit, and that detrimental changes may
threaten whale stocks, the IWC decided that the Scientific
Committee should give priority to research on the effects of
environmental changes on cetaceans. The Scientific Committee
examined this issue in the context of the Revised Management
Procedure and agreed the RMP adequately addresses such
concerns. However, it went on to state that the species most
vulnerable to such threats might well be those reduced to
levels at which the RMP, even if applied, would result in
zero catches. The IWC
has adopted Resolutions reaffirming its view of the
importance of these matters and encouraging the Scientific
Committee to increase collaboration and cooperation with
governmental, regional and other international organisations
working on related issues. Related research will be carried
out under the IWC's SOWER programme.
In addition to work at its annual meetings (during which
there is a sub-committee that addresses environmental
concerns), the Scientific Committee has held two workshops,
one on the effects of chemical pollutants in March 1995 in
Norway, and another on the effects of climate change and
ozone depletion in March 1996 in the USA. The two initial workshops
have been subsequently followed up by the development of two
multi-national, multi-disciplinary research proposals.
POLLUTION 2000+ had two aims: to determine whether
predictive and quantitative relationships exist between
biomarkers (of exposure to and/or effect of PCBs) and PCB
levels in certain tissues; and to validate/calibrate
sampling and analytical techniques. (Click
HERE for the
special issue on this topic).
SOWER 2000 examined
the influence of temporal and spatial variability in the
physical and biological Antarctic environment on the
distribution, abundance and migration of whales. The latter
programme involves co-operation with other major research
programmes including those of CCAMLR and Southern Ocean
GLOBEC. In addition to the whale information on the previous
link, general information about the cruises can be found on
the following links: UK SO GLOBEC; Australia SO GLOBEC and
US SO GLOBEC.
Subsequent to the two Workshops,
the Commission passed a Resolution in 1996 to establish a
Scientific Committee Standing Working Group on Environmental
Concerns to consider, and as appropriate act on the specific
recommendations of the two Workshops. The Standing Working
Group met for the first time in 1997. Since then, important
topics addressed annually include pollutant and contaminant
issues, physical and biological habitat degradation, impact
of noise, effects of fisheries, Arctic issues and disease
and mortality events.
Southern Ocean Whale
and Ecosystem Research Programme (SOWER)
In the mid-1970s, the IWC Scientific Committee
established a major research programme known as the
‘International Decades of Cetacean Research’. One of the
most important features of that programme was a series of
international cruises (independent from whaling operations)
in the Antarctic with the aim of obtaining abundance
estimates for Southern Hemisphere minke whales. The
‘easiest’ place to do that is in the austral summer when the
animals are feeding near to the ice. The first cruise took
place in 1978/79 using two vessels (and crews) generously
provided by the Government of Japan and with an
international group of scientists. The design of the
research programme is the responsibility of the IWC
Scientific Committee. This approach has been continued in
all cruises up to the present. Between 1980/81 and 1986/87,
the USSR also provided one vessel. The IDCR programme ceased
in 1996/97 and was replaced by the major new Southern Ocean
Whale and Ecosystem Research (SOWER) programme.
Largely in response to worries about the low abundance of
blue whales in the Southern Hemisphere, particularly in view
of their protection since the mid-1960s, a research
programme for large baleen whales was developed by the
Scientific Committee. The work on blue whales, in particular
has been incorporated into the traditional Antarctic
sightings cruises. The programme also includes the
collection of biopsy samples of skin from living whales and
acoustic recording of blue whale sounds to determine stock
and species identity and to improve abundance estimation
techniques for rare populations. As techniques develop,
increased emphasis will be given to integrated environmental
research linking cetacean abundance and distributions with
ecological factors.
The cruises have been successfully conducted for over 23
years with a total searching distance up to 2000/01 of
70,340 n.miles during 2,448 ship-days in the Antarctic. The
collaborative nature of the programme is highlighted by the
participation of 69 international researchers from 14
nations in the programme.
The cruises have provided a wealth of information on the
distribution and abundance of cetaceans in the waters south
of 60°S. An overview of the cruises can be found in the
following published papers:
Branch, T.A. and Butterworth, D.S.
2001. Estimates of abundance south of 60ºS for cetacean
species sighted frequently on the 1978/79 to 1997/98 IWC/IDCR-SOWER
sighting surveys. J. Cetacean Res. Manage.
3(3):251-70.
Branch, T.A. and Butterworth, D.S.
2001. Southern Hemisphere minke whales: standardised
abundance estimates from the 1978/79 to 1997/98 IDCR-SOWER
surveys. J. Cetacean Res. Manage. 3(2):143-74.
Kasamatsu, F., Hembree, D., Joyce, G.,
Tsunoda, L., Rowlett, R. and Nakano, T. 1988. Distribution
of cetacean sightings in the Antarctic: results obtained
from the IWC/IDCR minke whale assessment cruises, 1978/79 to
1983/84. Rep. int. Whal. Commn. 38:449-87.
Matsuoka, K., Ensor, P., Hakamada, T.,
Shimada, H., Nishiwaki, S., Kasamatsu, F. and Kato, H. 2003.
Overview of minke whale sightings surveys conducted on IWC/IDCR
and SOWER Antarctic cruises from 1978/79 to 2000/01. J.
Cetacean Res. Manage. 5(2):173-201.
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