. BLUE WHALES JANUARY ',1 2„—I-' r ^ „ /5 2! ^ ^^^ vi 2 6 r 3 2 /£ 7 5 \ ^^^V^^\\4 5 8 ? \ '"~\M*_J0 \ X. 73 3 13 3 ^^'' ,|<( Vf5, 6 113 Jz"~t'(y6}% 5 1 ). FIN WHALES FEBRUARY V X?..-!-' 4 5 Fig. 153. Whale distribution in January and February 1930 (from Kemp and Bennett, 1932). values at stations taken in January are shown as blacked-in circles and those in February as open circles. In January there is some, if only slight, correlation between the higher phosphate values and the lower pH values and between the lower phosphate values and the higher pH values. But in February
. BLUE WHALES JANUARY ',1 2„—I-' r ^ „ /5 2! ^ ^^^ vi 2 6 r 3 2 /£ 7 5 \ ^^^V^^\\4 5 8 ? \ '"~\M*_J0 \ X. 73 3 13 3 ^^'' ,|<( Vf5, 6 113 Jz"~t'(y6}% 5 1 ). FIN WHALES FEBRUARY V X?..-!-' 4 5 Fig. 153. Whale distribution in January and February 1930 (from Kemp and Bennett, 1932). values at stations taken in January are shown as blacked-in circles and those in February as open circles. In January there is some, if only slight, correlation between the higher phosphate values and the lower pH values and between the lower phosphate values and the higher pH values. But in February high and low phosphate values all fall within a very limited range of medium pH values, indicating that whilst the reduced phosphate content remains to point to a former phytoplankton production the corresponding high pH values have not been maintained by a continuation of phytoplankton activity, and have been reduced by a restoration of the C02 balance by gaseous exchange with the atmosphere. Fig. 152 shows the distribution of the average pH values for the top 50 m.; the area of lower pH values covers roughly the same area as that of the higher phosphate values off the north-east coast, but in addition extends far to the north. It should be noted that the three northern lines, with the exception of the two outer stations on the north-east line, were taken in January. If the hypothesis of animal exclusion is correct we should expect the whale distribution to correspond to the areas of high phosphate con- tent in January but not in February. This is what we find. The whales in February were reduced in numbers and were no longer concentrated off the north-east coast; this we
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