eet » Aetrs . ee wl es SRNR RETCe a OS CtSOR ns 0des oeee ORE GEIS TERS TIE Bee re eaa a in an environment where £065 is available, the more 60 Co it accumulates in the kidney, if 6 °G0 has a long biological halflife. This is not a concentration through the food web since the clams are filter feeders. The radionuclide content of bird species presents a sharp contrast, both qualitatively and quantitatively, associated with feeding habit (Table 8 and Appendix Table 10). The fairy terns and noddy terns feed mostly at sea outside the lagoon and contain small amounts of fallout radionuclides, naturally occurring 40, ‘of 137 Cs. The curlew, less than the amount of They contain barely. detectable amounts © on the other hand, feeds on the reef and on Scaevola sp. seeds, and consequently contains relatively large amounts of 13705, @s much as 2,300 pci/g dry in muscle. The turnstones also feed along the beaches and on the reef, and contain both 6066 and 137 a5, stones is not known, of sand particles. The source of 13765 for the turn- although it could be by direct ingestion The yellowfin tuna, which are feeding on essentially the same organisms as the terns, contain about the same levels of 6066 as the fairy terns. The 600, levels in the noddy terns are somewhat higher but still are of the same order of magnitude. Thus the area in which an animal is feeding is a factor affecting its radionuclide content, as expected, in relation to the distance from the source of the radionuclide. 9001388 nepartment of Energy Historian’s Office ARCHIVES