June 30, 2021
When I was out at the lake last week, I noticed a group of turtles resting on a log floating in the water. The vegetation around the lake came right down to the shore giving little area for the turtles to lay in the sun. I also saw only one log floating in the water for the turtles to rest on. Since turtles are cold-blooded animals, they need to regulate their body heat by the surrounding temperature. When turtles are too cold, they will slow down. If they are too hot, they will overheat and risk internal damage. That means the turtles alternate between warming in the sun and cooling off in the water. There were eight turtles resting on the log.
When I looked online, I found the Red-eared Slider (Trachemys scripta elegans) is one of 17 species of turtles which live in the ponds, lakes, and streams of Arkansas. In the wild they can often be found resting in the sun on a log or sand bar. Red-eared sliders are native to the southern US and northern Mexico. It is the most popular pet turtle in the US and is popular as a pet across the world. Since the Sliders are the most traded species of turtle, they are also the most invasive turtle in the world due to pet releases. The slider is included on the list of the world’s 100 most invasive species published by the International Union for the Conservation of Nature. This seems pretty busy for an animal who spends so much time resting.
Another name for a turtle resting in the sun is basking. When turtles bask, they absorb heat from both the sun and the substrate on which they bask. The sandy shore or the log they are resting on absorbs and gives off the sun’s heat. For North American turtles including sliders, the optimum temperature of the basking spot is between 90F to 95F. Exposure to UVB light enables turtles to produce vitamin D3, which is needed for the absorption and utilization of calcium. Drying out in the sun helps the turtle deal with fungal infections and parasites as those require moisture to live, as well as drying out the algae on the turtle’s shell, which will then fall off. Who knew resting could be so beneficial?
Thoughts: Some US states have laws and regulations regarding possession of Red-eared Sliders because they can be an invasive species where they are not native. It is now illegal in Florida to sell any wild-type red-eared slider, as they interbreed with the local yellow-bellied slider population (Trachemys scripta scripta). In Australia, the turtles are considered a significant threat to native turtle species, as they mature more quickly, grow larger, produce more offspring, and are more aggressive than native species. It seems these invaders are quite active when they are not resting. During the height of the pandemic many decided to forgo their usual vacations. Whether it was fear of losing a job, believing you were essential to your work, or finding nowhere to go with the country basically shut down, many workers powered through. Setting time aside for resting is just as important as being active during working hours. We need to learn from the Sliders. Follow the science. Change is coming and it starts with you.