The experience gained in this study indicated that Cervidae antlers afford a convenient means for measuring levels of ambient radioactivity over large areas. By the use of antlers, it was possible to compare Sr90 levels resulting from bomb testing “fallout” year by year from 1943 through 1958 in a number of areas in the United States, Canada, and Alaska. The most surprising finding was the very high levels for Alaska in 1958. From calculations based on total beta counts in antlers, it was possible to show that the radiation dose delivered to bone from short-lived fission products is insignificant as compared to the dose delivered by Sr90/Y90.