NUMBER OF | © FISH ey 14 = <1 I-2) 2-3 3-4 4-5 _ _sevewermed _| 5-6 6-7 7-8 NUMBER OF FISH TUNA CAUGHT NORTH OF THE EQUATOR 25 I9S7-68 Pmws ot 20L5—[Oo— "fennen a fees aeMy <j 1-2 2-3 eg 3-4 un TUNA CAUGHT SOUTH OF THE EQUATOR NUMBER OF FISH _ §E-9 HCI >>Fe/mg Fe PoSeca! re a <1 1-2 2-3 TUNA CAUGHT OFF BIKINI ATOLL Fig. 1. I967-68 nCi 5°Fe/mg Fe June 1969 nCi =5Fe/mg Fe Frequency distribution of Fg specific activity in Pacific Ocean tuna.