Many turtles, tortoises, and terrapins appear to sleep during a daily cycle. They pick a secluded spot with a constant, acceptable temperature; these reptiles then stop moving around and assume a particular posture, usually withdrawing into their shell for protection during “downtime.”
We caught Popeye again yesterday as he was going in for a nap in the afternoon. However, does he ever rest or even sleep? Humans sleep differently than turtles and tortoises. Consequently, turtles are more like in a resting state. Much as it depends on the species as to how they rest.
If They Do Not Sleep… Are They Tired?
Of course, sea turtles can sleep on the surface of the water when far out on the ocean deeps, Also, they wedge themselves under overhanging rocks or coral outcroppings to rest in shallow water.
In fact, when they are inactive, sea turtles can remain submerged for three hours or more without needing to surface for air.
Painted turtles bury themselves in sand or mud at the bottom of a pond to sleep. Therefore, absorbing oxygen from the water. Hense, semi-aquatics, such as the map turtle, may dig themselves partially or completely into a marshy area of grass or moss.
Do they hibernate?
Many turtle species live where they need to hibernate through the winter. Hibernation is a form of deep sleep from which the animal cannot be awakened easily. Almost all of its bodily processes slow down. As a result, it does not eat when no food is available.
Much as, in the Southwestern United States, the endangered desert tortoise hibernates during the coldest part of the winter in an underground den.
While it comes out to warm up on mild, sunny days.
The giant tortoises of the Galapagos and Seychelle Islands do not need to hibernate, but they do sleep during the cooler nights and often up to 18 hours a day, moving around only when they get warm enough.
Hibernation and brumation are really very closely related, they are periods of dormancy during which an animal becomes physiologically less active, their metabolic processes slow down, and growth stops. However, mammals and reptiles go into dormancy is slightly different ways, thus the terms hibernation and brumation.
Both reptiles and amphibians prepare for dormancy by eating more. They build up fat reserves in their bodies that can help them survive. Unlike mammals, the reptiles also build up a high level of glycogen in their body tissues as well.
Glycogen is a form of polysaccharide or sugar that can be used as energy for muscles. When mammals enter hibernation they rely solely on their fat reserves as energy to see them through winter. However, reptiles do not use fat as their sole source of energy. They mostly use the glycogen in their muscles with their fat reserves playing a greater role in reproduction, egg development, and post-dormancy mating
It’s even thought that some reptiles need brumation to trigger reproductive processes such as egg and sperm production.
Here’s a quick comparison chart:
|Hibernation (Mammals)||Brumation (Reptiles)|
|Caused by shortening day length and temperature changes||YES||YES|
|Animal may feed heavily before entering dormancy||YES||YES|
|Build up of fat reserve and lipids before entering dormancy?||YES||YES|
|Feeding and eating stop during dormancy||YES||YES|
|Drinking Water Stops||YES||No|
|Decreased heart rate, body temperature, and metabolism slow or decrease||YES||YES|
|Use stored fat for energy during dormancy||YES||YES/NO (glycogen)|
|Anoxia Tolerant (low oxygen)||NO||YES|
|Punctuated Activity||NO (most)||YES|