You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Radiation LD50 (30) of Pikas (Ochotona princeps) in the Natural Environment and in Captivity
O. D. Markham and F. W. Whicker
The American Midland Naturalist
Vol. 84, No. 1 (Jul., 1970), pp. 248-252
Published by: The University of Notre Dame
Stable URL: http://www.jstor.org/stable/2423742
Page Count: 5
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Estimates of the LD50(30) from 60Co radiation were made for a group of pikas (Ochotona princeps) held in captivity and for another group observed in the natural environment near the summit of Mount Evans, Colorado. The LD5030 estimate was 560 r (438-717 r; 95% confidence limits) for captive animals and 380 r (250-578 r) for pikas at Mount Evans. Mean survival time for irradiated pikas was 9 to 13 days in captivity and 5 to 7 days in the natural environment. Results are discussed in relation to artificial stresses resulting from captivity and natural stresses such as intraspecific competition and predation.
The American Midland Naturalist © 1970 The University of Notre Dame