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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.Wiley is collaborating with JSTOR to digitize, preserve and extend access to Ecology Abstract. Radiation doses received by small mammals inhabiting a dry radioactive leaching pond on the Idaho National Engineering Laboratory Site in southeastern Idaho were determined by surgically implanting lithium fluoride thermoluminescent dosimeter (TLD) chips. One hundred eightytwo TLD packets were implanted in 3 species: white-footed deer mouse (Peromyscus maniculatus), least chipmunk (Eutamias minimus), and Ord's kangaroo rat (Dipodomys ordii), with 65% recovery.All species from the radioactive leaching pond received significantly greater (P < .001) doses than control species. The deer mice received a mean dose equivalent rate of 160 mrem/day which was significantly greater (P < .001) than the mean dose equivalent rates received by least chipmunks (17 mrem/day) and Ord's kangaroo rats (6 mrem/day). The mean dose received by deer mice was 8% of the maximum air exposure recorded near the ground surface of the leaching pond. The maximum dose rate received by an individual deer mouse was nearly 50% of the maximum exposure rates in the study plot.Interspecific dose differences appeared to be related to habitat preference. Deer mice were most frequently captured on the gravelly and sparsely vegetated dry pond bed which had site exposure rates of 200 to 2000 mRoentgen/day. Conversely, chipmunks and kangaroo rats were usually captured on the pond banks which were adjacent to areas with sandy soil and denser vegetation. Site exposure rates on the pond banks ranged from 10 to 30 mRoentgen/day. Doses received by individuals of each species had high variation which appeared to be caused by the variable air exposure rates and the mobility of the small mammals. Intraspecific differences in activity, behavior and home range may have also influenced the dose variability in individual rodents.The advantage of implanted TLD over externally attached TLD and possible radiation effects on small mammal populations are discussed.

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Concentrations of 90Sr, 238Pu, 239,240Pu, 241Am, 242Cm and 244Cm were determined in tissues of mallard ducks (Anas platyrhynchos) maintained for 43-145 d on radioactive leaching ponds in southeastern Idaho. Highest concentrations of transuranics occurred in the gastrointestinal tract, followed closely by feathers. Approximately 75%, 18%, 6% and 1% of the total transuranic activity in tissues analyzed were associated with the bone, feathers, GI tract and liver, respectively. Concentrations in GI tracts were similar to concentrations in vegetation and insects in the littoral area of the ponds. The calculated total dose rate to the ducks from both 90Sr and the transuranic nuclides was 0.69 mGy d-1 (69 mrad d-1), of which 99% was to the bone. The potential effective dose equivalent to a human consuming the entire muscle and liver mass of one experimental duck with average nuclide concentrations was 0.46 microSv (0.046 mrem). Based upon average concentrations in experimental ducks and on surveys of wild waterfowl using this area, a conservative estimate of transuranic activity exported by wild ducks using the ponds during one year was 11.3 kBq (305 nCi). Similarly, the total amount of 90Sr exported in muscle, bone and lung of wild ducks in one year was 2.5 MBq (68.7 microCi).