Abstract
The biological proliferation of cesium-137 (137Cs) into individual birds in a forest ecosystem were examined. After the disastrous accident at Fukushima Daiichi Nuclear Power Plant in 2011, radionuclides, including 137Cs, have been deposited broadly over forested areas of northeastern Honshu, Japan. In forest, 137Cs became highly concentrated in leaf litter. The concentrations of 137Cs in the muscles and livers of five forest bird species were measured, and transfer factors from forest soil to birds were calculated. The values of transfer factors (TF) were equivalent to those reported from previous studies carried out after the Chernobyl accident. However, the TF value of Asian Stubtail Urosphena squameiceps was considerably higher than for the other bird species investigated and when compared with previously studies. Although the exact factors explaining the variation in 137Cs concentration among bird species could not be specified, the effects of foraging habitat and prey type are suggested.
