Sleeping Giants

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Swazi enjoys a nap.

Swazi enjoys a nap.

My favorite time to be with the African elephant herd at the Wild Animal Park is in the early morning. A few days each week, I sit at the Elephant Overlook between 6:30 and 8:30 in the morning and record the social interactions in the herd. This is a great time to look for social behavior because it is before the elephant keepers and the guests arrive, so the elephants are busy interacting with each other rather than with humans. The herd also tends to be very active in the early morning and oftentimes I find they are wandering the yard, trunk wrestling or even swimming in the pool!

However, one morning a few weeks ago the elephants weren’t active at all; in fact, quite a few of our elephants were still asleep! I am frequently asked how elephants sleep, and you may be surprised to hear that they do sleep lying down. The popular assumption is that elephants always sleep standing up, which can be true for a quick cat nap. However, elephants lie down on the ground when they sleep soundly for a few hours each night. There are even records of elephants snoring while deep in sleep! I have also seen at least one of our adult females, Swazi, kicking her feet while sleeping, much like dogs do when they are dreaming.

We are continually learning about the nighttime patterns of the herd through the data we are collecting from our elephants’ GPS collars, which are worn for 24-hour periods to record their movements (see post, How Far Do Elephants Walk in One Day?). We are able to plot the GPS points onto a map of the Wild Animal Park elephant yard and see exactly where that elephant was at any given time. What we have found is that some of our elephants may have preferred sleeping spots, as noted by repeated GPS points in certain locations over a few nighttime hours. For example, it seems our dominant female, Swazi, wanders into the indoor barn to sleep for a few hours, whereas another female, Ndula, seems to prefer the pool at the far end of the yard (when it is empty, of course!). So our GPS collars not only tell us how far the elephants walk and where they walk, but also let us know where they like to sleep.

Emily Rothwell is a Heller Fellow Research Associate with the San Diego Zoo’s Institute for Conservation Research.

Watch the Park’s elephants daily on Elephant Cam.