All animals prepare for winter differently. Squirrels and chipmunks collect and hide food in the fall, many birds migrate or fly south, while other animals eat large amounts of food in the fall to gain body fat and then find a nice warm place to sleep through winter such as bears, frogs and turtles. Animals that do this are called “hibernators”. Hibernation is when an animal is in an inactive state for a period of time. To be a true hibernator the heart rate of the animal must slow down and their body temperature needs to drop down to near 0OC. That’s almost at the Freezing Point! This then makes it hard for the hibernator to wake up quickly. Even though bears are said to be hibernators they are not true hibernators because their body temperature does not drop very much, and they are easily awaken from their winter slumber. Turtles though are considered to be true hibernators and their hibernation is called Brumation.
All of Ontario’s turtles hibernate throughout winter and their hibernating sites are located usually at the bottom of ponds, lakes or deep under the mud. Doing this allows their body temperature and heart rate to drop so much that their body does not need to eat during the winter. Turtles are able to slow down their heart rate to almost nothing. Normally a turtle’s heart beats about 40 times a minute when basking in the sun in the summer, but during hibernation their heart beat drops down to about one beat every 10 minutes. WOW!
You may be asking yourself if turtles breathe air, how can they sleep all through winter under water? The answer to this puzzling question is just another amazing way turtles have adapted to their environment!
They are able to survive under water because the water that is at the bottom of the ponds and lakes contain more oxygen and are actually warmer than the surface water. To overcome their inability to breathe under water, turtles have adapted special tissue in their throat and tail opening that is able to take in oxygen that is in the water. This means that they are able to breathe through their throat and tail!
Hibernation is just one of the many vulnerable times in a turtle’s lifecycle. During hibernation their body slows so much that their immune system begins to shut down, which means that they are at high risk of getting really sick or even dying. Due to this sick or injured turtles should not hibernate and this is why the Kawartha Turtle Trauma Centre is so important. All of the sick or injured turtles that come into the Centre that do not heal in time for winter hibernation are kept at the Centre. We care for the turtles through winter so they will be healthy and ready to go once the spring and warm weather return.