さあ！諸君！捕鯨問題だ！

1974年のIWC科学委員会報告で、南半球ミンククジラ総個体数概数30万頭の
決め方については前年の報告書(IWC/24 p42)を見よと書いてあったので気に
なってました。

一応資料としてその部分と、そのすぐ後のシエラ号に関する言及部分原文だけ
紹介しておきます。

Minke Whales

16. Document SC/25/9 presents an estimate of the initial population size of
Antarctic minke whales at 299,999 with an estimated MSY of 12,230. Chapman
(SC/25/32) believes that this estimate of MSY is much too large and that a
more reasonable estimate on the basis of analogy with other species is about
5,000. Ohsumi insists that the population size was reasonably revised on the
basis of improved sighting coverage in 1972/73 and therefore Chapman's estimate
is unreasonably too low even in the light of the last report. Best and others
believe that the estimate of population size, which is based entirely on
sightings data, must be considered provisional bearing in mind that it has
been radically revised from the 1972 estimate (150,000 +) due to a single
season's observations. The Committee noted that both estimates of MSY are
based on assumptions regarding the values of critical parameters and that
there is as yet no sound basis for determining which is the more accurate, but
it emphasizes the importance of a conservative approach. The stook certainly
has a surplus above the MSY level. Utilization of this surplus should be
managed cautiously until additional information is available. Studies on the
validity of the sighting data and additional biological studies must be made
as soon as possible. Catches should be distributed over the several Areas so
as not to deplete the population in one or two Areas (see Annex F).


BALEEN WHAIES IN THE SOUTHERN HEMISPHERE OUTSIDE THE ANTARCTIC

17. The Committee noted the activities of the "Sierra" operating in the
South Atlantic under the flag of the Republic of Somalia, and of their offer
to Mr Vangstein to assist in marking operations. It suggests that the
Chairman communicate with the operators urging that they obtain scientific
assistance in identification of their catches and in the proposed marking
operations and urge their continued cooperation in providing data to the
Bureau on catch and effort.

以上、国際捕鯨委員会第24回年次報告（1974年刊行）42ー43頁より引用