Finding the cubs required some caution, particularly in making sure Mom was not home. The researchers waited until Lidya's radio signal indicated that she had left the den site before searching for the cubs, which they found in a collection of rocks on the slope of a hill. Two of the cubs, who weighed from 12 to 14 pounds, remained calm as the researchers handled and measured them, but the third spent most of the time "roaring" at its captors. After collecting hair and blood samples for genetic and disease analysis, the team fitted them with radio collars and returned them to their den.
The cubs represent Lidya's fourth litter since she was fitted with a radio-collar in 1999. "Lidya is probably the most successful tigress we've collared since we started this project in 1999, not just because she's had lots of litters, but because she's a careful mom and most of her cubs survive," said John Goodrich, a WCS researcher and the head of the Siberian Tiger Project. WCS has been monitoring tigers in the Russian Far East since 1992.
Through radio telemetry, WCS has gained critical information about the needs of Siberian tigers, an animal so elusive that few field researchers have seen them in their natural habitat. Researchers are particularly