Amur tigers' living area expands fast

The number of Amur tigers, also known as Siberian tigers, relocating from Russia into northeastern China is rising because of lower levels of human activity, improvements in their habitat and a smoother transit corridor between the countries, tiger experts said.

Research team calculates that the area the tigers inhabited across the Sino-Russian border expanded by about 12 kilometers every three years from 2003 to 2016.