Russian scientists started Friday an expedition to track the endangered snow leopards in southern Siberia, the RIA Novosti news agency reported. A research team will travel to the Altai-Sayan mountainous region to collect data on the snow leopard population and its habitat range. This is the third phase of the expedition \"On the Trail of Snow Leopards.\" The results will be presented in late November. In 2010, Russia launched a five-year program to study and monitor the snow leopard population in southern Siberia. Under the program, a reserve will be set up in the western Sayan region for the conservation of the snow leopard. The snow leopard is a rare and quickly vanishing animal, which ranks as Category 1 -- critically endangered -- on Russia\'s list of threatened species. The number of snow leopards in Russia was 150 to 200 in 2002. The number might have been further reduced as a result of poaching.