the supply was diminishing.
C.
Geographical Distribution of Radioactivity in the Algae
Intertidal zone.
The average levels of radioactivity of specimens
of three genera of algae, Caulerpa, Lyngbya, and Halimeda, collected
in the intertidal zones of eight islands of the atoll at intervals from April
1954 to April 1956 are given in Table 3.
Before May 14, 1954,
the highest levels were found in algae samples
fcom Vera Island (35 uc/kg) and Olive Island (21 uc/kg), the lowest at
Elmer Island (0.26 we/kg) and Leroy Island (0.28 uc/kg),
ate levels at the other four islands.
samples
from
Vera
and intermedi-
The rapid radioactive decay in the
and Olive Islands and the data from the survey
for gamma radioactivity at Vera Island showed that fallout from the March
1854 tests at Bikini Atoll had contaminated this area of the atoll.
After May 14, 1954, the highest initial values were found in the algae
from Leroy Island and the lowest in those from Elmer Island.
The levels
of radioactivity in the algae from the northern half of the atoll were generally higher than those from the southern islands.
study this pattern remained much the same.
of the
at
Over the period of
The levels of radioactivity
algae collected at Belle Island were similar to those collected
Alice
Island (one mile away)
and Vera Island (ten miles away).