Biologically, moose sleep just like their deer relatives do, by laying on their side, curling up and resting their heads on their bodies or legs. To create a suitable place to sleep, moose simply stomp down the ground by walking in circles.
Encounters North explains that moose can be very vulnerable to predators, such as wolves and humans, when traveling through or sleeping on deep snow. Accordingly, moose often choose to lie down directly on trails on which they have been travelling. This is thought to be an adaptation that allows them to smell predators before they get too close.