Why do deer perform ‘circle dances’? 

The animals gather in a herd and together circle around the same spot, moving relatively fast and in unison. They do this both in the tundra and when penned in corrals.

It turns out that the herd behaves like this when the animals feel agitated. For example, when they sense a wild animal nearby or are being bitten by gnats in the summer. While going round in a circle, they wait for the lead reindeer to act and then they calm down. On hot days, reindeer can move nonstop for 12 hours until they get tired. Usually, they move counterclockwise.

Reindeer have a strong herd instinct and repeat one another's and their leader's movements, believing it to be safer this way. Reindeer in the outer circle can end up moving closer to the center during the “circle dance”. The minimum size of a reindeer group is 20 animals.

Reindeer herders also know how to make the animals perform a “circle dance” when they need to drive them into a pen or capture animals needed for harnessing. To do this, they get the lead animals to start circling and all others begin to follow suit.