How To Care For Soft-shelled Turtles

At a glance, they look like pancakes with a snorkel. Their peculiar form is distinctive: a flat, leathery carapace; flipperlike forelimbs and paddlelike rear feet with long, sharp claws; a long neck capable of lashing out faster than the blink of an eye; and a powerful head with a tubular proboscis and fleshy lips, hiding sharp, slicing jaws capable of delivering a serious bite. Soft-shelled turtles are unique and highly evolved, and despite their apparently specialized adaptations, they flourish in practically all aquatic habitats within their natural range.

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The average adult softshell may need a tank up to 200 gallons or more, so plan accordingly.
 

Depending on the species or subspecies, the coloration of a “softy” varies from tan or light brown to gray or almost black, sometimes with blotches, flecks and reticulations. This cryptic camouflage allows them to blend in with their surroundings remarkably well, and their flattened profile allows them to scuttle quickly and easily below the substrate to further enhance their ability to hide from predators, but also to ambush their own unsuspecting prey as it swims unknowingly past a hidden turtle. There are often stripes on the head and neck which also vary depending on the type of softshell, and these stripes sometimes fade or disappear entirely with age.

There are three well-established species of soft-shelled turtle native to North America. They are the spiny softshell (Apalone spinifera), which is divided into seven subspecies; the smooth softshell (A. mutica), which is divided into two subspecies; and the Florida softshell (A. ferox), with no recognized subspecies.

Spiny Softshells

​In addition to having the most subspecies, the spiny softshell also has the widest distribution of the native North American species. It shows a preference for rivers, but can also be found in associated lakes, ponds, and marshes with soft bottoms and moderate vegetation. It is distinguished from the smooth softshell by the pointed tubercles, from which it gets its name, along the anterior margin of the carapace, and from the Florida softshell by the lack of a dermal ridge around the margin of the carapace. Female spiny softshells sometimes grow quite large, up to around 21 inches. Males normally reach less than half that size, up to about 81/2 inches.

The eastern spiny softshell (A. s. spinifera) occurs east of the Mississippi River from eastern New York southward to western Virginia and North Carolina, and Tennessee. There are disjunct populations in extreme southern Quebec along the Vermont/New York border, east-central New York, and south-west New Jersey. The carapace pattern consists of large, black ocelli (rings) and a single black marginal line.
The Gulf Coast spiny softshell (A. s. aspera) occurs from south-central North Carolina westward to southeastern Louisiana, through all contiguous states with the exception of peninsular Florida. In this subspecies there are two or more black marginal lines, and the head stripes are joined at the tympanum.

Before you Buy a Softie
Taking on a soft-shelled turtle is a big responsibility. Consider some important points before you commit to owning one.

• Soft-shelled turtles will get big. Although the average size is around 12 inches, they are capable of growing up to almost 2 feet.
• They will live for a long time. Captives are known to live up to 50 years and possibly longer.
• Soft-shelled turtles can be very aggressive. At any size, this can present a hazard to smaller tankmates. At larger sizes, they can even be dangerous to the keeper.
• If size or aggression present potential problems for you, a soft-shelled turtle is definitely not your best choice for a pet turtle. Choose another!

The black spiny softshell (A. s. atra) is endemic to Cuatrocienegas Basin of Coahuila, Mexico. The carapace is dark overall and apparently lacks any distinct markings.
The Texas spiny softshell (A. s. emoryi) occurs in the Pecos and Rio Grande Rivers of New Mexico and Texas, and the Colorado River drainages of Utah, Nevada, California, Arizona and New Mexico. The pale rim of the carapace is four to five times wider along the rear margin than along the sides, and the head stripes are typically broken resulting in a post-orbital (behind the eye) blotch.

The Guadalupe spiny softshell (A. s. guadalupensis) occurs only in south-central Texas in the Guadalupe/San Antonio and Nueces Rivers. This subspecies possesses narrow black ocelli and white tubercles over the entire carapace.
The western spiny softshell (A. s. hartwegi) occurs west of the Mississippi River from Minnesota and southern South Dakota westward into southeast Wyoming and eastern Colorado and New Mexico, and southward into northeastern Louisiana. There is also a large, disjunct population in Montana, and a small disjunct population in east-central Colorado. There is a single black marginal line and consistent black ocelli and spots on the carapace.
The pallid spiny softshell (A. s. pallida) occurs east of the Rio Brazos in eastern Texas and in the upper Red River region of Oklahoma to northwestern Louisiana. The carapace is pale and possesses white tubercles that are actually larger toward the rear of the shell and diminish in size toward the front. No black spots or ocelli are present.

The Smooth and Florida Softshell Turtles

​The smooth softshell shows a marked preference for large rivers with moderate to swift currents. Waterways with a sandy bottom and few to no rocks or aquatic vegetation are favored. It is distinguished from the other native North American species by a complete lack of knobs or tubercles on the carapace. Adult females are capable of reaching up to 14 inches in length, while males are known only up to about half that size.
The midland smooth softshell (A. m. mutica) occurs primarily in the Mississippi, Missouri, Kansas, Arkansas, Red, Colorado, Ohio and Cumberland Rivers. This subspecies is also occasionally found in lakes and marshes, and is distinguished by indistinct dark spots and short bars on the carapace. There are also pale stripes with thin black borders on the snout and head.

The Gulf Coast smooth softshell (A. m. calvata) occurs in watersheds along the Gulf Coast, including the Escambia, Alabama, Pascagoula and Pearl Rivers. There are large black spots and ocelli on the carapace, and pale stripes with thick black borders on the snout and head.
The Florida softshell turtle shows preference only for soft-bottomed waterways, and is equally likely to be found in large rivers as it is in livestock watering holes. It occurs from southern South Carolina westward to the eastern shore of Mobile Bay in Alabama, and southward to the tip of peninsular Florida. Distinctive characteristics of this species are the rounded nodules along the anterior edge of the carapace and the dermal ridge around the rim of the carapace. Hatchlings and young juveniles are often strikingly patterned, with yellow to orange mottling on a dark-gray to black background, with a bold golden rim around the carapace. Unfortunately, this beautiful coloration fades with age, and adults are typically drab gray to brown. This is the largest of the North American soft-shelled species, with females capable of reaching almost 23 inches. While males are smaller, they still reach a very respectable 13 inches.

Softshell Turtles Enclosures

Housing soft-shelled turtles in a community tank can be a risky proposition for both the softshell and any potential companions. Although softshells can normally cohabitate quite peacefully with other softshells as well as other turtle species, there is always the potential for conflict. Observation is required when keeping softies with other turtles, and they should be removed from the group at any indication of a problem. If they are able to assert their dominance, a softshell can swiftly become the tank bully and monopolize food and other resources. Even if they do not actually physically harm other turtles, softshells are capable of intimidating them to the point where the other turtles will stop feeding. Conversely, if another turtle begins nipping at the fleshy margin of the softy’s shell, serious injury can result.

Although they are hardy, adaptable and willing to eat just about anything, soft-shelled turtles can sometimes be difficult to adjust to captivity. As always, a captive-bred soft-shelled turtle is preferable to one taken from the wild. Captive-bred turtles are accustomed to housing under artificial conditions from the moment they hatch, are much less likely to be diseased or harbor parasites, and generally tend to be less aggressive than their wild-caught counterparts.

Softshells are accepting of a variety of housing arrangements, but they definitely require some specific conditions in order to remain healthy and active. Their tank must be provided with a sand substrate, or otherwise the water must be filtered with mechanical/biological/chemical filtration. Large, abrasive stone objects should be avoided. The leathery skin of a soft-shelled turtle’s shell is living tissue that is susceptible to injury and infection. Burrowing into and scooting about under the sand substrate helps exfoliate the shell. This removes bacteria and fungi, and stimulates regeneration of new, healthy skin. Without this provision, soft-shelled turtles are very susceptible to shell-skin infections that can eventually become systemic and kill the turtle.

What To Feed Softshell Turtles

Watching soft-shelled turtles feed can be a fascinating and exciting event. They’re highly animated feeders, and nearly any edible material plunked into the tank will be eagerly devoured by a softshell.
Live or pre-killed fish, insects and worms, as well as commercial fish and turtle pellets, are all appropriate fare for soft-shelled turtles. Fish and other live prey items will be hunted, pursued and ambushed, while pellets and other non-living items will be gobbled off the surface of the water with a quick gulp. Anything too big for a softshell to swallow whole will be torn to pieces by the turtle’s shearing jaws and piercing claws.

The basking habit is well developed in soft-shelled turtles, so suitable basking accommodations must be provided if they are to remain healthy and vigorous. Basking raises a turtle’s metabolism to facilitate digestion and bolster the immune system. It also allows the skin to dry completely, which enhances the benefits of burrowing mentioned previously. Failure to provide sufficient basking sites will lead to a whole host of potential health problems, including skin infections, shell rot, and ear abscesses, just to name a few. Natural and artificial platforms, such as driftwood and commercially manufactured plastic, should be placed in stable configurations extending down to the bottom of the tank. Creative arrangements also contribute to the aesthetic appeal of a softshell tank, and a safe structure below the water’s surface can also provide a secure hiding spot. Care should be taken so that the structure can be safely crawled upon, in and around without trapping the turtle below the water’s surface, causing it to drown.

Softshells are excellent swimmers, and there is no limit to tank size. A turtle should be allowed 5 to 10 gallons of water per inch of carapace length at a minimum, and the tank provided should be as large as possible. This means that the average adult softshell may need a tank up to 200 gallons or more, so plan accordingly. And because they are lively, vigorous turtles, tank furnishings should be securely set into place to prevent any shifting or damage. Keep in mind that even a large, strong soft-shelled turtle can become trapped under a substantial object and drown!
Heat lamps and aquarium heaters can be used to regulate temperature ranges for pet soft-shelled turtles. Softshells are quite active, so titanium heaters are strongly recommended. If a glass heater is used instead, it should be used with a guard or protective shroud to prevent breaking. Water temperatures should be kept in the range of 70 to 80 degrees Fahrenheit, and air temps should be a few degrees warmer, around 75 to 85 degrees. Temperatures for the basking spot should reach upward of 90 to 100 degrees at its hottest point.

These temperatures can be allowed to drop about 5 degrees at night, and another 5 degrees or so during the winter. In nature, wild softshells can endure temperatures well outside their optimum activity range, but subjecting captive turtles to these extremes is not necessary or recommended.
Hatchling and juvenile soft-shelled turtles can be set up in something as simple as a mortar tub, with live or plastic plants and a water-safe chunk of driftwood for basking and hiding. As previously mentioned — and this cannot be stressed enough — a sand substrate should be provided for health and welfare. Other substrate media, such as crushed coral and river pebbles, should be avoided. As long as vitamin D is supplemented via a nutritious diet, a basking lamp is really only necessary to provide heat and light, and temperatures described above for larger softshells are appropriate for hatchlings as well.

Soft-shelled turtles are as remarkable in their form as they are in their behavior. Although in certain respects they can be somewhat delicate, in others they can be aggressive, as well. While they are capable of growing quite large and living a very long time, when their essential needs and requirements are fulfilled they make excellent captives. Their housing requirements are fairly straightforward and they are not finicky eaters. Remember, though, that soft-shelled turtles are not necessarily the best choice for a community tank. Still, for the dedicated keeper, these intriguing creatures make delightful captives and will provide ample reward for the keeper’s effort. 

PAUL VANDER SCHOUW is an avid turtle hobbyist from west-central Florida. A mechanical engineer by profession, he has about 1,000 individual turtles representing more than 100 species and subspecies. He has successfully bred more than half. Chelid side-necked turtles are his primary interest.