Polar Bear tracks disappear into the other worldly landscape of ice and snow on the frozen Chukchi Sea near Point Hope. The great bears continuously roam the ice in search of seals and the remains of whales that have been caught. By average weight, Polar Bears rank as the world’s largest bear. However, the Coastal Brown Bears of Kodiak Island and the Chignik River drainage on the Alaska Peninsula can weigh as much and stand taller. April 26, 2012
CutterLight 
They walk in one line, that is a surprise
They have a lot of territory to cover.
Their tracks are in one line and they have four legs.
I see what you mean. Interesting.