Thousands of reindeer starved to death in Arctic Russia in 2006 and 2013 due to unusual weather conditions linked to global warming and climate change, a new report revealed.

A team of researchers led by Rovaniemi, Finland-based Bruce Forbes of the University of Lapland, found that 20,000 reindeer starved to death in 2006 and nearly 61,000 died in 2013.

The researchers blamed Arctic sea ice retreats caused by global warming for the unprecedented deaths of the reindeer in the region. The same unusual weather conditions in the first half of the month of November led to both famines.

Forbes noted that reindeer are used to sporadic ice cover, but the species encountered severely unusual conditions in those years. The month of September this year saw the second-lowest level of ice cover in Arctic Sea on record, and there is big chance of another famine.

Speaking on the topic, Forbes said, “If we see such events again this year, it could mean that they’re becoming more frequent. Now is the risk window, and if it happens again, it will be a major problem for traditional reindeer herders still suffering from losses in 2013.”

Temperatures plunged to minus 40 degree Celsius in the region during winter, suddenly turning snow into impassable, solid ice for months that prevented reindeer from access food.

The shocking findings reinforced concerns about the potential hazardous impacts of unusual weather conditions on wildlife as well as traditional Arctic communities.