The Chernobyl disaster, a nuclear reactor explosion and subsequent fire on April 26, 1986, which spewed highly radioactive fallout into the atmosphere, continues to harm animal populations in the Ukraine, according to a new study. The study, published in the latest Royal Society Biology Letters, presents the most extensive data set ever compiled on the abundance of animals at and around the Chernobyl site. "Abundance" is relative in this case, however, since scientists Anders Moller and Timothy Mousseau determined that insect, bird and other animal populations have dramatically diminished there in the two decades following the disaster.

"Chronic, continuous exposure to low dose radiation appears to be the cause," Mousseau, director of the Chernobyl Research Initiative at the University of South Carolina, told Discovery News.

For three years, he and Moller conducted population censuses on invertebrates at more than 700 sites near Chernobyl. At each site the researchers measured radiation levels, using Geiger counters and aerial scan data. They also counted numbers of bumblebees, butterflies, grasshoppers, dragonflies and spider webs.