Sesetait cians + en 15 in an environment where 6000 is available, the more 6° G0 it accumulates in the kidney, life. if 60% has a long biological half- 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 405. ‘of 13765. The curlew, on Scaevola sp. seeds, less than the amount of They contain barely detectable amounts on the other hand, feeds on the reef and and consequently contains relatively large amounts of 137G6, as much as 2,300 pCi/g dry in muscle. turnstones also feed along the beaches and on the reef, contain both 60K and 13705, stones is not known, of sand particles. The and The source of 13705 for the turn- although it could be by direct ingestion The yellowfin tuna, which are feeding on essentially the same organisms as the terns, same levels of 60% as the fairy terns. contain about the The 6006 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.