While many turtles thrive in mixed-species enclosures, it is best to house common snapping turtles singly. While zoos and professional institutions may occasionally house snapping turtles with red-eared sliders, amateur turtle enthusiasts should avoid the practice. While the ranges of both species overlap and they inhabit the same bodies of water, they frequent different microhabitats. Further, snapping turtles are voracious predators that will consider other turtles prey.
The Food Chain
Whether crawling through the mud of the Mississippi bayou or lurking at the bottom of an aquarium, common snapping turtles (Chelydra serpentina) view small animals as potential food. If your snapping turtle is much larger than his tankmates, he will eventually eat them. Even if they are approximately the same size, he may bite off their appendages. While large adult red-eared sliders (Trachemys scripta) may safely cohabitate with a hatchling or juvenile snapping turtle, it will not take long for a well-fed snapping turtle to surpass them in size. Though most are smaller, large slider turtles reach a maximum of about 12 inches; by contrast, snapping turtles grow to about 18 inches in length.
Many aquatic turtles require relatively large habitats that exceed the space their keepers can provide – habitats for multiple animals must be even larger. Each red-eared slider requires about 4 to 6 square feet of swimming space and a few more square feet of basking space. By contrast, an adult snapping turtle requires about 15 to 20 square feet of space -- far larger than most commercially produced aquariums. A tank for multiple animals must be even larger than this.
Though both species inhabit some of the same lakes, rivers and swamps, they prefer to dwell in different portions of these waters. Red-eared sliders are basking turtles that spend a lot of time basking on exposed rocks and logs in relatively deep and open water. By contrast, snapping turtles prefer weed-choked shallows with muddy bottoms. Keeping both species in the same enclosure requires providing both types of microhabitat – further increasing the total size of the pond or tank. While such different preferences may slightly reduce the danger of predation, it is no guarantee that the red-eared sliders will not venture through the shallows, or vice versa.
In general, snapping turtles are not appropriate pets for most turtle enthusiasts. Even if you keep them alone, the combination of their large size and often-unpleasant disposition make them challenging to maintain safely; adding more turtles to the mix only complicates the situation. By contrast, when kept with appropriate tankmates, red-eared sliders make excellent tenants in community tanks. House them with other basking species, such as painted turtles (Chrysemys picta) or yellow-bellied sliders (Trachemys scripta), that are similar in size.