Project Sedan: Influence of a Cratering Device on Close-In Populations of Lizards
Abstract
Prior to the Sedan test on July 6, 1962, the density of adult lizards northeast of the prospective ground zero was estimated on the basis of repeated sampling of selected areas. Samples were taken by hand collecting and by means of buried cans, which served as traps for both lizards and various species of arthropods. Measurements of cumulative gross gamma dosages in the study areas were also made: at 2" and 36" above the ground, 2" below the ground, and in the tissues of lizards by means of small implanted glass micro-dosimeters. The shrubby areas northeast of ground zero, the pre-test density of Cnemidophorus tigris in June was estimated at 5-10 per acre, the density of Crotaphytus wislizeni at 1-2 per acre. No juveniles of either species were observed. Densities of Uta stansburiana and Phrynosoma Platyrhinos could not be estimated from the data acquired. After the test, during August and again in November, no adult lizards were observed closer to ground zero than 5500 ft. However, adult lizards were only rarely observed in areas which experienced neither blast damage nor lethal levels of gamma radiation. Hence, except, within about 2000 ft of ground zero, the apparent low incidence of adult lizards after the test cannot be ascribed to the detonation. A period of inactivity of adults may be involved. The impact of the detonation, if any, on adult lizards may be more clearly manifested in the spring of 1963, when definite evidence of differential survival as a function of distance from ground, ground zero may be obtained.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 20, 1962
- Accession Number
- ADA436767
Entities
People
- Frederick B. Turner
Organizations
- University of California, Los Angeles