. 1 r 3 A- 1 â 5 1 6 1 7 1 6 1 1â 9 IO YEARS "I- II OF II' 12 13 AGE 1 14 1 15 1 16 ~i r 20 21 TWO-YEAR GROUPING O PREGNANT WHALES---* LACTATING OR RESTING WHALES - -C Fig. 2. Fin whales, females. Numbers of each age group in the total catch of five seasons: mature whales only. likely, that the old whales do not linger in these waters. They may even avoid the locality altogether on their way farther south. Edser further calculates from these figures the number of immature females that must become mature in order to keep the stock at a constant level, and also the number of young females t
. 1 r 3 A- 1 â 5 1 6 1 7 1 6 1 1â 9 IO YEARS "I- II OF II' 12 13 AGE 1 14 1 15 1 16 ~i r 20 21 TWO-YEAR GROUPING O PREGNANT WHALES---* LACTATING OR RESTING WHALES - -C Fig. 2. Fin whales, females. Numbers of each age group in the total catch of five seasons: mature whales only. likely, that the old whales do not linger in these waters. They may even avoid the locality altogether on their way farther south. Edser further calculates from these figures the number of immature females that must become mature in order to keep the stock at a constant level, and also the number of young females that can, in the most favourable circumstances, be produced by the mature stock. By equating the sum of the first six terms of the algebraic series to the sum of the first six catches1 a has been calculated, and with a equal to 497 and r to 26 per cent the theoretical catches based on the series and the stocks of whales in the corresponding /i - (1 - o-26)6\ o-20fl ââ =415, the sum of the first six terms of the actual catch: from which a=4Q7. \i - (1 -0-26)/ * J +v/
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
