ELKordatum 1955 Co60 toy retrieving experiment Nov. 27 Big Spring Canyon, Tilden Park, Contra Costa Co. Calif. Attempt to evaluate effectiveness of tagging method by searching out tagged toad and salamander with Geiger counter (Tracerlab Bx survey meter) and scintillometer. Used sloping (about 20°) grassy hillside in area where Bob Stebbins has worked Sceloporus for pinned body studies. Stebbins, daughter Melinda, son John helped out. Bobbinio Dead Canyon 12 <-- 22 yds --> grass 25 yds Above area mentally staked out as limits for hiding the animals. Dry dead grasses (cusha etc.) to about one foot height. Small rocky outcroppings scattered through grass - none larger than 1+ foot across and 10-12 " above ground. Soil moist due to downslope seepage following recent rains. Clear sunny skies. Time 1:15 - 2:10 p.m. Procedure was for 2 of us to plant the animals while other some 50 yards away with backs turned. Moved with instruments parallel to each other about 4-5 feet apart. Scintillometer was much more effective in picking up responses 8-12 feet away, but Geiger counter still effective. Results on separate sheet.