From Justin Cooke
Winden, Germany
Your article about the recent meeting of the International Whaling Commission
(IWC) and its scientific committee (This Week, June 29, p 4) refers to a working
paper of mine as “criticising the committee for not doing enough computer
simulations”. The issue was somewhat more complex.
There were two procedures on the table for estimating the abundance of minke
whales in the North Atlantic, one developed at the Norwegian Computing Centre
(NCC) and one developed here at the Centre for Ecosystem Management Studies
(CEMS). For reasons still to be elucidated, the NCC program estimates
considerably higher numbers of whales than does ours, although comparable
estimates are not yet available from the most recent (1995) survey.
The committee developed quite an extensive set of simulation tests, but only
the CEMS program could be put through them all because the NCC program is very
complicated and needed too much computer time to perform the tests. Despite
this, the committee opted for the NCC system. It was the logic behind this
decision that I questioned in my working paper.
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The IWC has a formula, called the Revised Management Procedure (RMP), for
determining the allowable catch (“Blood on the water”, June 22, p 12). The
abundance estimate is put into this formula. Since the RMP formula has an
inbuilt margin of safety, use of an overestimate of abundance will not endanger
the whale population in the short term as long as the error is recognised and
corrected before too long. The committee could therefore agree on using the
higher estimate in the RMP. The committee also inserted a new provision into the
RMP rules which allows abundance estimates to be revised retrospectively if they
are subsequently found to be wrong.
Estimating the numbers of whales is a difficult but ultimately soluble
problem. Unfortunately, the politicisation of the issue has not made its
resolution easier. There is concern that to allow any scientific discussion of
this matter could be interpreted as an admission that the accepted estimates are
less than final: in such an atmosphere progress will inevitably be slow.
