Peninsula Cooter Species Overview & Care Guide

The Peninsula Cooter species of turtles have dark shells with vivid patterns and are closely related to River Cooters. These turtles grow quite large and can live up to 30 years!

In this guide, you’ll learn:

  • What makes a Peninsula Cooter unique?
  • How do you properly take care of a Peninsula Cooter?
Peninsula Cooter Turtle

Species Overview

Appearance & Colors

The Peninsula Cooter is a stunning species of turtle that is often very large and has a dark shell with vivid patterns. This species also can grow quite large and has thin yellow stripes on its head, neck, and legs. The bright patterns, particularly in young Peninsula Cooters, make these turtles a very attractive species as pets. 

Their claws can grow particularly long in males, and females can get very large compared to males. Males will often have larger tails compared to females as well. Both males and females get more rounded rather than a streamline looking species like the Red Ear Slider. 

Peninsula Cooters are closely related to River Cooters but differ in a few key ways. The Peninsula Cooter lives in similar habitats to River Cooters, Red-Eared Sliders, Painted Turtles, and a variety of other species of turtle. Telling a Peninsula Cooter apart from others can often be difficult, but their large size can be very telling. 

Average Size

Peninsula Cooters grow to different sizes depending on whether they are male or female. As in most species of turtles, males are smaller than females. In Peninsula Cooters, males are smaller and less round, reaching sizes of about 6-10 inches across their carapace. Females on the other hand, can exceed a carapace length of 12 inches and often reach up to 16 inches in size. 

Females need to be larger in order to store eggs in their bodies. Males need longer nails in order to perform their mating dance with females. These sizes will vary based on the diet and age of the turtle. Young turtles may grow quickly at first but will slow down as they age to about 1/2 inch of growth per year until they reach their maximum size. The plastron, or underside, of these turtles, will be slightly smaller than the carapace. 


Like most species of turtles, Peninsula Cooters can live a long time, so make sure you’re ready for a lifelong commitment. These turtles can live up to 30 years or more if cared for properly. A variety of factors will determine the life span of the Peninsula Cooter, including water quality, diet, and environment. 

High water quality, a proper and diverse diet, and room to grow are key to making sure they live a long life. Predators in the natural habitat of the Peninsula Cooter will shorten the natural lifespan of this turtle, including raccoons, alligators, crows (for younger turtles), bass, and herons. Most turtles have evolved in order to survive extreme conditions, therefore providing a quality environment for your turtle will guarantee a long-living animal. 

Behavior and Temperament

Despite sharing similar habitats, Peninsula Cooters are shyer than sliders or painted turtles. They bask for significant portions of the day to increase their body temperature and will forage for plant material and food items with the rest of their time. Increasing their body temperature by basking will help them digest their food. 

Like most species of turtles, Peninsula Cooters can be aggressive in groups to one another or other turtles without proper space. Males may compete for females in the wild and fight. Females can be territorial and also fight as well. The Peninsula Cooter may also interact with other species. 

Pro-tip ⚡

Be cautious when handling a Peninsula Cooter, as they will often bite in self-defense if they are not used to human interaction or handling. The large size of these turtles makes the risk of injury higher than in normal-sized turtles.

Most pet Cooters are adapted to captivity so captive-bred Cooters will not be nearly as aggressive as in wild-caught turtles. They may even become friendly and swim towards humans in search of food and snacks. 

How To Care For Peninsula Cooters

Housing The Peninsula Cooter

For housing hatchling and juvenile Peninsula Cooters, aquariums often work as a primary option. Clear sides allow you to view your turtle and interact with them more than other housing options. A water depth of 4-6 inches is recommended for hatchlings. 

Make sure there are plenty of plants or decorations for the turtles to use to climb to the surface for a breath of air if they need one. While Peninsula Cooters are excellent swimmers, young hatchlings may need help getting to the surface for a breath of air. 

Peninsula Cooters may appreciate a spot to hide, such as a cave or piece of driftwood. Be careful not to create a drowning hazard. Despite being water turtles and aquatic species, these turtles can still drown if stuck underwater. 

An area to fully dry is also necessary for the Peninsula Cooters, especially because they love basking. This species is known to very frequently sun themselves in the wild, and do this as well in captivity. A 20-gallon aquarium will work very well for a hatchling Peninsula Cooter turtle. 

As the turtle grows, the aquarium size should be increased. As the turtles get older, they become better swimmers and will enjoy more depth and area to swim. A 40-gallon tank will work well for a 3-4 inch turtle past the fragile hatchling stage. A transition to a stock tank or pond may be best for larger and adult Peninsula Cooters to make sure they have enough space to thrive. 

A depth of 12 inches will work well for turtles 4 inches in length and larger. A minimum of 125 gallons is suggested for an adult female Peninsula Cooter, however, a larger enclosure will work better. The maximum space you can provide for this species is recommended.

Pro-tip ⚡

Many keepers use agricultural stock tanks or liner ponds to create a big enough space for their Peninsula Cooters. Aquariums are not often made large enough to house these species, as they can grow to very large sizes. 

A substrate on the bottom of the enclosure is not necessary for this species, however, sand will work well and looks great. Make sure you wash the sand before use to avoid cloudy water. Regular play sand can be used effectively, but ensure it is well washed by pouring the sand in a bucket, and running water through it until it runs clear. 

Small gravel or pebbles may be ingested and cause impactions and complications in your turtle, so it is best to avoid it. Gravel and larger rocks may also hold waste and material, rotting under the rocks and decreasing water quality. Adding substrate to your Peninsula Cooter habitat may look good, but it will often need extra maintenance to maintain good water quality.


Peninsula Cooters enjoy warm water, as they are from the Southeastern United States and Florida. Water temperatures of 76 to 82 degrees Fahrenheit work well. Hatchlings should be housed in water 82 ˚F. Adults can handle lower temperatures in the 70’s; however, 76˚ is a safe number to aim for and will encourage basking. A heater may be required if these temperatures are higher than room temperature in your household. A heater will also make sure temperatures will stay stable, so they are recommended for most Peninsula Cooter setups. 

📚 Read More >> Best Turtle Tank Heaters


Peninsula Cooters love to bask, so providing an area to fully dry off is very important. A heating lamp should be placed over the area at a distance so it reaches about 90 ˚F or so. The enclosure should also have a UVB fluorescent light to provide UVB light and radiation to the turtles. This is necessary for the turtles to synthesize vitamin D3 and absorb calcium from their diet. A mercury vapor bulb will provide both UVB radiation and heat and is a good option rather than two separate lights. 

Food and Water

Peninsula Cooters eat mainly plant material and are herbivores. As hatchlings, they will eat more protein than when they become adults. Be careful not to overfeed your turtle, as they can quickly become obese and overweight. Feeding every day or every other day is recommended for hatchlings and 2-3 times per week as suggested for adults. 

A diet of shrimp, insects, earthworms, or fish are the ideal protein options for hatchlings to supplement a staple pellet diet. Adults and juveniles will enjoy mustard greens, romaine lettuce, vegetables, turnip greens, dandelion greens, spinach, carrots, and squash. These turtles will also eat aquatic plants such as duckweed, water hyacinth, or water lettuce. Most pellets are also sufficient but should be supplemented with plant material. 

Maintaining Good Water Quality

Keeping high water quality is necessary for keeping a healthy turtle. Make sure that you utilize a strong filter to avoid health issues in the future. Using a strong filter rated for 2-3 times the size of the aquarium will also reduce the number of water changes you need to do. Maintenance will also reduce if you invest in a more powerful and better filter. 

📚 Read More >> How To Fix Cloudy Turtle Tank

Fun Fact

Peninsula Cooters are from ponds and rivers and are therefore used to a large amount of aquatic vegetation that keeps the water quality high. There is also a high oxygen content in most of the habitats of the Peninsula Cooter because of the high water movement or current. 

If you fill the enclosure using tap water, make sure to remove the chlorine from the water. Chlorine can irritate the eyes of a Peninsula Cooter. A dechlorinator made for reptiles specifically, turtles will work well to accomplish this. Water changes are necessary to ensure high water quality and avoid health problems. A good rule of thumb is to change 25% of the total water volume per week. This will remove nitrates, which can build up and become toxic to inhabitants in the aquarium or enclosure. 

Common Health and Behavior Problems

Poor water quality can lead to a variety of illnesses in Peninsula Cooters. Respiratory infections are common in habitats that are too cold. Shell rot can occur if your Peninsula Cooter does not have an area to fully dry off and bask. Skin or fungal infections can occur in animals that are not in clean and fresh water. Eye infections are also common in unsanitary conditions. 

Metabolic bone disease is also a common condition stemming from a lack of calcium and vitamin D3 due to poor UVB lighting. Supplements and proper lighting will help prevent this.

Tips For Handling

Moderate handling of your Peninsula Cooter will ensure they become better acclimated to humans. It is not recommended to handle your turtle too often, as they can quickly become stressed out. 

Avoid putting your hands near the front of your Peninsula Cooter, as they may bite in self-defense. Using two hands, firmly grip your Peninsula Cooter from the back to hold it properly, but be careful of their powerful back legs. Handling is mainly advised for health checks and not for entertainment, as it easily agitates the turtle.

Can More Than One Peninsula Cooter Live Together?

If Peninsula Cooters are given enough space, they may be housed together. They are often more likely to get along as hatchlings rather than as adults. As they grow up, Peninsula Cooters can become more territorial and aggressive to one another. 

Even turtles that have never shown aggression to one another may randomly have disputes over territory, which can lead to injury. Significant space is required for housing two Cooters together. Plenty of hiding spaces and visual barriers will also help maintain peace. 

How To Choose A Peninsula Cooter

Signs Of Good Health

A healthy Peninsula Cooter is willing to eat a variety of food items, will have bright eyes, and be alert to its surroundings. It will also be a strong swimmer and be reactive to the environment around it. A turtle that is not eating, lethargic, or generally inactive should be avoided.

Shell Condition

The shells of Peninsula Cooters should be strong and brightly patterned, without visible pits or divots in the shell that may be a sign of shell rot. Shell rot is often caused by not having a place to fully dry and allow the turtle to sun itself as well as poor water quality. Shells should not bend when pressed slightly in adults though shells are a bit softer in hatchlings.

Eyes & Skin

A Peninsula Cooter should have clear, bright eyes. This is a sign of good health and water quality. The skin should not have any blisters or sores, or discolored spots as well. The eyes and skin will help you determine whether their water quality is good enough or not. Poor water quality leads to cloudiness or puffiness in the eyes or fungus spots on the skin. 


Are Peninsula Cooters aggressive?

Peninsula Cooters can be aggressive toward one another if they are not provided ample space to swim and live. They can also be aggressive towards people they do not recognize or are more willing to bite if removed from their habitat. Be cautious if handling a Peninsula Cooter. 

How big do Peninsula Cooters get?

Peninsula Cooters can reach 8-10 inches as males and reach sizes of up to 16 inches as females. These are a particularly large species and you should have a large enclosure ready for when they grow up!  Hatchlings will often grow very quickly but slow down as they get larger. It is not uncommon to have 1-2 inches of growth per year for the first few years of a Cooter’s life until they reach about 4 inches. 

Can you hold a Peninsula Cooter?

With caution, you may handle a Peninsula Cooter for a short amount of time. This should be avoided if possible to avoid stressing out the turtle unnecessarily. Health checks and handling of your turtle are important every so often to make sure they look healthy. 

Visually, you should look for irritation to the eyes or skin, as well as any fungal marks on the shell. Taking a Peninsula Cooter outdoors for natural sunlight may also help improve their quality of life. Watch them carefully, as they can quickly run away and escape most outdoor setups, even temporary ones. 

Do Peninsula Cooters bite?

Peninsula Cooters can bite in defense if they feel threatened. Holding a Cooter from the back of the shell can help avoid a bite. Feeding your Peninsula Cooter and establishing a good relationship with the turtle may help avoid aggression and biting tendencies. Peninsula Cooters will often open their mouths before biting, so you should note this and avoid their mouth if they are showing this behavior!

Dan Roselli

Dan Roselli

Dan has raised, cared for, and rehabilitated turtles for over 10 years. His most recent turtle project involves two rare spotless white Ornate Diamondback terrapins!

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Dan Roselli

Dan Roselli

Dan has raised, cared for, and rehabilitated turtles for over 10 years. His most recent turtle project involves two rare spotless white Ornate Diamondback terrapins!

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