Swans gather on a partially ice-covered lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. About 600 swans annually migrate to the lake, which is heated by warm springs, where they spend their winter being fed by yagers, which helps them to survive the severe cold. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans gather on a partially ice-covered lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans gather on a partially ice-covered lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans gather on a partially ice-covered lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)

Swans swim over a lake, with the air temperature at about minus 35 degrees Celsius (minus 31 degrees Fahrenheit) as steam ascends above the water during sunset near the village of Urozhainy, Sovetsky district of Altai region, January 26, 2015. (Photo by Andrei Kasprishin/Reuters)