- ae : Sgtpl de te ae ad ee we ae University of Weshington Seattle 5, Washington December 11, 195% C % . Comments on apo in Land Crabe re.: Or. oa teymnour's letter of December 4, 195f: the sr?° levels in land erabs can be expected to remein econstznt (excepting physical decay) over 4 period of years. This statement is based on the data resulting from repeute! collections at Belle Islan’, Eniwetok, during a period of two years following Nectur test. The radloactivity in the carapace (exoskeleton) aue to long lives Lsotopes remained approximately constant at a level of spproximately. 10,000 d/m/e wet throughout a period of 23 months during which collections were made. Rudiochemical analysis of 15 samples taken at varfious times suring the collecting period, and three samples taken 35 days before Nectur test demonstrated thet virtually 100% of the ~ ao long lived isotopes was Sr “and its x70 daughter, The land crabs being onmivorous can probably be consiceres an index of biologically avallable strontium, However, the ratio of the strontium to that in fooc ttems is not known. Juiging from the meager data presently available the radiostrontiws content of the crab skeleton is more than ten times that in land plants on a wet weight busis and is more than threes times that in soil on a dry weight oasis. The data from the Belle Island collections indicates that turnover of strontiun in the land crab skeleton is rapit. The