51
5.2 August 1958 Rongelap Survey
5.21
Gross beta and total gamma radioactivity.
Exami-
nation of the data from the survey of radioactivity in the
fish collected at Rongelap Atoll in August,
1958,
suggested
that an arrangement of the fish in a 2-way classification
based on
(1)
range of movement and
(2)
feeding habit would
provide a useful basis for comparisons of relative levels of
radioactivity from which inferences could be drawn as to the
distribution of radioisotopes in the environment of these
fish.
Table 2 shows average relative values of gross beta
'
and total gamma radioactivity in fish classified by increasing range as local,
as herbivores,
ranging and roving; and by feeding habit
omnivores
and carnivores.
further classified as pelagic,
The carnivores were
coral and benthic feeders.
These classifications were intended to be general,
and to
reflect the predominant feeding choice of the fish involved.
In the strictest sense,
all probably are omnivores,
as vege-
table or animal food is undoubtedly taken in adventitiously
in varying amounts by species feeding preferentially on either.
Incomplete information on some of the variables which
normally affect radioactive counting efficiency necessarily
AN
b
restricts the use of beta and gamma radioactivity data shown