AECD-3446

134

ANALYSIS BY AREA
The data were analyzed with the purpose of estimating radioactivity by

areas, by species, by tissue, and by feeding habits.

Analysis by area was baseq

on the average activity of all fish sampled from one collecting area.

Table 1

summarizes these data by comparing d/m/g of wet tissue of fish and of fish liver

with each collecting area and also gives collection date, counting date, and habitat
or depth of water from which collected. The average d/m/g per fish was higher
at Eniwetok Atoll (142) than at Bikini (33) or Likiep Atolls (1.2). A similar relation.
ship is seen in the activity of the livers (see Figure1).
The most active areas of Bikini Atoll, listed in descending order, were
the Target Area, off Bokon Island, Ruji Pass, Amen, and Namu Islands.

The

d/m/g in liver tissue show a similar picture, but with Ruji second to the Target
Area,

The activity of the three most active areas - Runi Pass, off Bokon Island,

and the Target Area - were based upon counts of samples from larger than average
fish caught in fairly deep water (30 feet or more); whereas the fish from other

areas were taken from the shallow waters of the reef.

There is no way we can

separate these factors of size and depth of water inasmuch as the larger fish are
taken in deeper waters.

In the case of Ruji Pass the results are surprising be-

causethisis the first indication of activity spreading in any considerable magnitude
(compared with the neighboring shallow waters) in this area.

The pattern, as

revealed by the activity in the fish generally, indicates fairly extensive contamination especially to the northwest and east of the Target Area and apparently to the
southwest through the deep water channels emptying the atoll water.

Our data are,

of course, fallible in that we do not have enough large fish from the deep waters
of otherparts oftiie atoll although several unsuccessful attempts were made to ~
obtain these by fish traps.

Also, considering the variations in activity that occur

in fish from the same area, possibly we do not have representative samples from
each area,

The correlation between radioactivity and deep water and /or larger fish
was seen in the 1947 resurvey (UWFL-7, Figure 11) in which collections of large
fish from deep water around coral heads averagedhigher than those from shallow
waters of smaller fish.

This pattern was not evident in the 1948 resurvey

~ UNIVE
.
UNty, ontm

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