ceepny ee cee cane Kreg mse oe ~ beeline itn ae ee DASA 2019-2 196 WARREN: Per body mass. AYRES: You mean the concentration phenomenon doesn't extend right up to the top? WARREN: What he's saying is that there isn't very much of tne radioiodine ingested with any one fish because the thyroid is so small in terms of the body mass of the shark. AYRES: So peak concentration is found in the lower forms then? BUSTAD: That's right, and the radioiodine may destroy the thyroid or severely damage it and by then there will be no radioiodine left. [It leaves the thyroid due to physical decay and biological turnover. DONALDSON: There's another difference. The physiology of the shark is quite different from that of the bony fishes. BUSTAD: But we have to admit, [ think, that many of those fish that Gorbman picked up down there relatively early manifested severe thyroid damage but were probably not compromised from the standpoint of your cleanup squad. I mean he got there before they were appropriate subjects for the cleanup squad, AYRES: Are there any turtles in the area? DONALDSON: Turtles are net gregarious animals. They just don't like to have people around. They are there, true, but when the 4,000 or 5,000 members of the test group descend on the place, the turtles go elsewhere. The turtles are back at Bikini now that the test group has departed. Ihope we car—if the Chairman will allow us to—take a look at a film showing how the place looks now. WARREN: I think we've left a little dangling in the discussion, You said the plankton have a diurnal change in depth, whatever their -location. Does it occur in the atolls where the depths may be 200 or 250 feet or thereabout, as well as inthe open ocean? The shallow waters you mentioned were meant to be the shallows, weren't they, at depths of 15, 20, 30 feet?