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Red-Eared Sliders, otherwise known as Red Eared Terrapins are turtles that belong to the Emydidae family. They are semiaquatic, meaning that they spend a decent amount of time in the water, but also need some time on dry land as well.
Red-Eared Sliders are the most common pet turtle in the United States of America and our top pick as the best turtle for beginners. They are also popular across the globe. These invasive species originate from Mexico and the Southern United States.
Due to their popularity and household pets it’s important to know how large they will grow and how to best prepare.
How Big do Red-Eared Sliders Get in Length?
Newborn Red-Eared Sliders are about one inch in diameter.
They are considered one of the largest pond turtles. Turtles that have been given ample space and food can grow to be as large as 12 inches in length.
Female Red-Eared Sliders are usually larger than males in size. In rare cases, a Red-Eared Slider will grow to be larger than 12 inches. On average, most turtles held in captivity range from being six to eight inches in length.
How to Measure Your Red-Eared Slider
A Red-Eared Slider’s size is usually measured according to the straight inch length of their shell (also referred to as the plastron). You can use the following method to measure your turtle’s shell growth over time.
- Place your turtle on its back. The turtle might not like this, but it should be safe for them as long as you place them on their only for the amount of time it takes to measure them.
- Using a measuring tape, measure your Red-Eared slider from the start of the shell to the turtle’s tail up to where it ends, close to the head.
- Record your turtle’s size on a notepad and do this on a monthly or yearly basis. That way, you will be able to keep track of your beloved pet’s growth.
Factors that affect the Growth of Red-Eared Sliders
The growth of Captive Red-Eared Sliders depends partially on the amount of food and space given to them.
Turtle Environment and Space:
A turtle that is being held in an open, large environment will grow to be much larger than a turtle that is kept in a smaller space. In general, an adult, Red-Eared slider that is 10 inches in length would need a 100-gallon tank to thrive. If you buy a tank that is too small for your turtle, you are risking its growth potential and might cause your turtle to be very unhappy.
Red Eared Sliders Diet:
Diet is also a huge factor in whether the red-eared slider will reach its full genetic potential in size. Red-Eared Sliders need a balanced diet of calcium, protein, and healthy green vegetables. Red-Eared Sliders are omnivores but they tend to be more on the carnivore side in their younger years. Therefore, it is crucial to feed them enough protein so they can have strong tissues and muscles.
The best kind of protein to feed your pet turtle is the type of protein they would prey on in a free environment (animal protein). Examples of animal protein to feed your Red-Eared Slider includes earthworms, shrimp, aquatic snails, crickets, and daphnia. If you are feeding a baby turtle, make sure you cut up the prey into smaller pieces before feeding it to them.
It is also important to feed your Red-Eared Slider lots of leafy, green vegetables. You want to choose greens that are high in vitamins and nutrition. Examples of green vegetables to feed your turtle would be kale, bok choy, collard greens, spinach, peas, and dandelion greens. You also want to make sure the vegetables you are feeding them have high phosphorus levels. Avoid feeding your Red-Eared Slider iceberg lettuce or celery because these foods have very little nutrition.
Another crucial part of a Red-Eared Slider’s diet should include Calcium. Calcium helps make the bones and shell of a turtle strong. If a baby Red-Eared Slider is deprived of Calcium, they will not be able to grow to their full potential. Lack of Calcium can even kill your Red-Eared slider. One excellent source of Calcium to feed your Red-Eared Slider is Cuttlebone.
Cuttlebone is a chalky, white substance that you can feed your turtle. You can throw a block of Cuttlebone in their tank to give them something to munch on. You can make cuttlebone yourself or buy it commercially.
You can also throw in a vitamin supplement with Calcium in the tank to provide your Red-Eared Slider with the nutrient. The vitamin tablet will dissolve into the water and the turtle will absorb the calcium water into their skin over time.
Feeding your turtle a balanced diet and providing them with a tank that holds ten gallons for every inch of shell they have will give them the best chance of reaching their full growth potential.
It is important to remember that all Red-Eared sliders grow at different rates and to different sizes (just like humans). Different species of Red-Eared Sliders are naturally different sizes. Sometimes, you can give a turtle all the space they need and the best diet possible, but they will still be a smaller turtle, simply due to genetics.
How much do Red-Eared Sliders Weigh?
The average, adult Red-Eared Slider weighs about 8.5 OZ.
Growth Process for Red-Eared Sliders
The fastest growth for Red-Eared sliders happens during their first years. They can grow up to three or four inches in the first year and ten to grow one inch every year after that until they reach their full, genetic potential. These kinds of turtles tend to reach their full size between the ages of five to seven years old. It is important to remember that all Red-Eared sliders grow at different rates and to different sizes (just like humans).
Red-Eared Sliders During the Winter
Unlike other turtles, Red-Eared Sliders do not hibernate during the winter. They tend to brumate which means to stay inactive for the most part, but they will rise on occasion for water or food. Red-Eared sliders tend to eat way less in the winter months than in summer due to their brumation process.
Red Eared Sliders are one of the best types of turtles to have as a pet. In regards to overall size, they can grow up to 12 inches at the largest and will weight around 8.5 ounces.