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A typical sleeping bout includes 30 seconds to a few minutes of dozing, followed by a brief alert period, and then more dozing followed by an alert period. This cycle often lasts for about 30 minutes. Generally, once per 30 minutes deer will stand and stretch and they may urinate or defecate before laying back down. They may even stand, urinate in their bed and lay back down in it. This 30-minute cycle of rest and standing has also been reported in the literature for axis deer.
Whether dozing or sleeping with eyes open or closed, deer are continually monitoring what is going on around them. Their ears are never lowered, and they can wake up instantly. Dr. Rue feels their ears may even be more important than their nose while they are sleeping. Charlie says bedded deer are very cognizant of what goes on around them with regard to squirrels and turkeys. Their senses are so incredibly keen that they can distinguish between squirrel activity and a snapping branch.