Where do deer sleep?
Roe deer are a secretive species and as such, it is very unusual to find one asleep whilst we’re out for causal walk in the countryside. But even an animal as nervous as a roe deer, needs to sleep — the question is, where?
The short answer is that they tend to conceal themselves inside of a bush or somewhere obscure in a wood, but I have known them to doze in the open expanse of a field. And I will discuss mention that again, further down this post.
Relatively few long, deep sleeps
Humans tend to sleep for long stretches of time, 7, 8 or 9 hours (or more) at a time. But as a prey species, roe deer can’t afford do the same thing.
In parts of Europe, where are lynx and wolves roam the countryside, falling into a deep slumber would be fatal; instead, they employ a strategy of taking many short naps, spread throughout the day. So, even though there are no natural predators of adult roe, the deer in England, Scotland and Wales, adopt the same approach to getting their required quota of rest.
After spending whole days (daylight hours only!) with groups and individual roe deer and studying photographs from remote cameras, I estimate that an adult roe will have been 5 and 8 periods of rest in a 24 period, when they will close their eyes and properly sleep, albeit for only short periods.
Finding the right spot
The most reliable time to observe wild roe deer asleep is a couple of hours after their early morning feeding period. Deer tend to be most active at either end of the day, but first light is the most consistent time of all to see them.
After a prolonged feed, the deer will move to a quiet place to regurgitate and thoroughly chew their food; this is process is called ruminating.
Before laying down, they will sniff the ground and scrape at the substrate. If the ground doesn’t smell right, they will move on and try somewhere else.
Once they find a suitable spot, they will lower themselves down to the ground, front end first and lay down in a position similar to that of a dog.
Roe deer are very much creatures of habit; assuming human interference levels and weather conditions remain constant, they tend to retire a favourite lie, time after time.
On a several occasions, where one deer has taken another animal’s favourite couch, the deer whose favourite lie has been taken, will approach the other ‘intruding’ individual and touch them with a front foot, or sniff along their back, which always causes the recumbent deer to rise to their hooves and vacate the lie, after which they usually settle down again a few feet way.
This behaviour seems restricted to bucks (adults and youngsters); I have never seen a doe (either an adult or a fawn) try to displace an adult buck. Also, this is normally only seen during the winter, the deer are more sociable.
Falling asleep follows a predicable pattern
After laying down, the deer is unlikely to fall asleep straightaway. It is will spend a lengthy period of time looking around, just to make sure the coast is still clear.
If deer feels safe, it may start to ruminate, or it may just lay there looking around, gradually getting drowsier and drowsier. Its eyes will start to close and the head will often start to sway, as the neck muscles relax. Sometimes, his or her head will start to sway or tilt to one side, until it almost hits the ground and the deer suddenly becomes alert again.
Eventually the inevitable happens, and the deer lays its head down to sleep.
Once the head is down, the eyes will initially close and the ears will (to a certain extent) relax. As the deer drifts into a deep slumber, the eyes will flicker; rapidly opening and closing, often with the white of the eyeball showing. Its ears will switch about, flicking one way and them the other. Sometimes part of their body twitch too.
This will continue for at least 30 seconds. After that, the deer will either wake-up, or there will be another period with the eyes staying closed and the ears staying relatively still.
Normally, the time for which the roe lays down its head and closes its eyes to rest, doesn’t last much longer than a couple of minutes. The longest time I have recorded for a deer to sleep deeply is 24 minutes, however this is rare. Usually, a roe will reach its required amount of sleep by taking many short naps.
Although a deer with its head down and eyes closed does increase its vulnerability, the ears and nose are still active and will quickly alert the individual to approaching dangers.
Choice of location
Earlier in this post, I mentioned that for most of the time a roe deer will select an area of dense cover, like a bush to rest in. But they will on occasion sleep in the middle of an open field.
There are two main factors which play a significant role in where the deer choose to lie down to rest: security and weather.
Security is the most important one; a deer will not place themselves in a recumbent position, if they don’t feel safe.
A roe is far less susceptible to being picked off by a marauding predator or killed by a person with a gun, if it is concealed within a hidden enclosure of bush-line, or in a secluded location within a wood, where the dappled light falling through the canopy breaks up the deer’s instinct outline. Dense of cover also provides some degree of protection against wind chill effects, if a strong wind is blowing.
But as previously mentioned, roe deer also rest in an open field, if they feel safe to do so. Normally, this is when the grass is sufficient long and the field is not frequented by people.
Inclement weather, especially driving rain, will preclude them using open ground, as the wind and rain can drive moisture deep into their coat and come in contact with their skin.