MIGRATION OF PLUTONIUM FROM FRESHWATER ECOSYSTEMS 633 



route of biological mobilization from the pond. However, they do not contain more than 

 4 X 10"*% of the plutonium in the pond or more than 1 x 10~^% of the inventory in 

 pond biota. 



Estimates of goldfish production in U-Pond fall within production ranges for suckers 

 and carp reported by Carlander (1955) for a number of North American lakes and 

 reservoirs. This goldfish population appears to contain about 4 X 10^ nCi of plutonium, 

 less than 1 x 10~^% of the plutonium in all the pond biota and less than 1 x 10~^% of 

 the entire pond inventory. Goldfish are occasionally eaten by herons, coyotes, and 

 waterfowl. 



The bulk of material in the pond is, of course, in the sediments (Table 1). They 

 contain about 99% of the entire mass of the pond's ecosystem (excluding water). 



