three-inch,
sample.
solid crystal.
Counting time was 30 minutes per
The output data from the 256-channel analyzer were
processed by an IBM Model 709 computer.
All values were corrected for decay of the radionuclide
during the period between the estimated date of catching the
fish and the date of counting the sample.
The date of catch was.
arbitrarily assumed to be the mid-point between the first and
last days of fishing for the vessel from which the sample was
obtained.
"Month of catch" rather than "month of landing" would
be another logical way of grouping the data, but the error in
estimating the date of catch did not warrant changing the
original method of grouping the data as established by Kawabata
et al.
(1963).
In accumulating the data on the radioactivity of the samples
three variables were recognized:
radionuclide.
month of landing,
tissue and
Species and area were recognized only for special
analyses; there was little species difference and segregation by
area was unwarranted because of the widely scattered fishing
areas and the migratory habits of the fish.
first group,
The samples in the
identified as "May", were from fish caught before
the initiation of the 1962 program at Christmas Island and therefore can be considered to be
"pretest" samples.
The average values for each of seven gamma-emitting radionuclides in four tissues of eviscerated tuna--light muscle, dark