Keeping Your Turtle or Tortoise Healthy
R.D. and Patti Bartlett
If you want a pet reptile that will be with you 20, 30, even 40 or more years after you acquire it, choose a turtle or tortoise. Turtles are semi-aquatic species and box turtles, and the term tortoise refers to the land dwelling true tortoises.
Captive turtles and tortoises of most kinds are reasonably easy to keep healthy. They require a proper diet, vitamin and mineral supplements, and proper caging conditions. Proper caging includes humidity, microhabitat, temperature, space, and security.
Turtles and tortoises offered in pet trade are usually hatchlings. At a shell length of from one and a quarter to two inches, the bright-eyed babies are endearing creatures that even confirmed herpetophobes (people with a fear or hatred of most reptiles) find cute and approachable.
At hatchling size, three or four turtlets can be kept in a properly appointed 10-gallon tank (no plastic turtle bowls sporting plastic palm trees, please). It's difficult then to perceive that these creatures can quickly grow to an adult size of six, 10 or even 14 inches in shell length. They will require 75- to 150-gallon tanks.
No matter their size, all semi-aquatic turtles require ample space and clean facilities. To prevent abrasion to the lower shell (plastron) the land areas and/or haul-outs should be easily accessible and smooth. To lessen the possibility of bacterial and fungus-caused shell pitting or skin problems, the water should be kept clean, filtered and be frequently changed. Ultraviolet (full spectrum) lighting will also help deter skin problems.
Box turtles are closely allied to typical semi-aquatic turtles, but they are almost exclusively terrestrial. They require a sizable land area, with rather high humidity for the more easterly forms and low humidity for the more arid-dwelling western forms. A shallow dish of clean drinking water should always be available, but water for swimming is not needed.
Temperature and Humidity
Tortoises also dwell in terrestrial habitats. A few occur in the proximity of forested swamps (forest hinge-backed tortoises) or in the forests themselves (yellow-footed tortoises). Others are forest-edge and seasonally wet savannah dwellers (red-footed tortoises), but most inhabit semi-arid (Hermann's, spider and leopard tortoises) to aridland environments (Kleinman's tortoises).
A high cage humidity will often debilitate an aridland species or tortoise, and a rainforest species will be distressed when cage humidity is too low. A slightly moistened non-aromatic mulch (such as cypress bark) can be used as a substrate when high humidity is desired, and dry earth, desert sand or dry mulch when an arid environment is desired.
Turtles and tortoises must also feel secure in the water and on land. Hideboxes, plantings, sunken driftwood and other visual barriers will help accomplish this. All must be situated to allow the chelonians to take full advantage of them, but they must be of such form (and secured) so the turtles and tortoises cannot be wedged and trapped behind or beneath them.
Suitable cage temperatures, of both land and water, are also important. In general, water temperatures of 72 to 84 degrees Fahrenheit (78 to 84 is best) will keep your semi-aquatic turtle of temperate origin active. The setup becomes ideal when it is provided with a warmed (94 to 102 degrees), exposed basking spot illuminated by full spectrum heat lamps. These are available on the Web or through ads in reptile magazines.
Tropical basking and aquatic turtles thrive best when water temperatures are 80 to 88 degrees.
Veterinarians disagree on the subject of routine endoparasite purging. Many turtles and tortoises (especially collected from the wild) bear a rather remarkable gut flora and fauna (bacteria, protozoans, worms). Proliferation of any of these is entirely undesirable.
Purging often destroys both good gut flora and fauna (those that assist in breakdown of plant material) and bad gut flora and fauna. Whether to do so is a veterinary decision. Assessment and treatment becomes mandatory when the health of the turtle or tortoise is compromised – when its weight falls or stress has allowed endoparasites to proliferate beyond reasonable levels.
The Importance of Diet
Some turtles are omnivores, some are piscivores (fish-eaters), some eat snails and crustaceans, others, along with most of the tortoises, are primarily herbivores. In captivity, most species will readily accept an alternate diet (one differing from that eaten in the wild).
The diet we use for our omnivorous semi-aquatics consists of greens (mustard, collard, beet, dandelion and turnip), aquarium plants (such as Anacharis, Hydrilla and Valisneria), freshly killed minnows, chopped nightcrawlers, crickets and pellets of koi, trout and catfish chows. There are well-formulated commercial aquatic turtle foods that would probably suffice as a complete diet, but it's best to provide the mixture of fresh ingredients.
Box turtles eat the animal matter listed above, as well as some of the greens. You can also add berries and other fresh fruit, crickets and some mealworms.
Tortoises eat the various greens (to which we add clovers when they are in season), a little fruit and a little low-fat dry cat food once a week. Although most adult tortoises munch happily on entire leaves and halved fruits, we have found that baby tortoises eat best when their food is finely chopped.
Vitamin and mineral additives can be important to the long-term well being of turtles and tortoises. This is especially so for turtles and tortoises kept indoors. To understand why, consider the complex interactions between A and B ultraviolet rays and production/metabolizing by reptiles of vitamin D3 and calcium.
Encapsulating the procedure, UV-A promotes natural behavior in reptiles and UV-B allows vitamin D3 to be synthesized. In turn, the presence of D3 allows calcium to be properly metabolized. Thus, when a turtle or tortoise is kept indoors and denied access to unfiltered UV rays, the production of D3 and use of calcium is seriously inhibited. Full-spectrum bulbs do provide UV, but so far, there is nothing readily available that can truly compete with natural sunlight.
It becomes apparent, then, that additives – specifically D3 and calcium – should be given as a matter of course to chelonians when they reside indoors. They should be administered more frequently (twice weekly) to fast-growing baby turtles and tortoises and ovulating females, but only once weekly (or even once every two weeks) to adult chelonians. It is less necessary to administer supplements to the diet of turtles and tortoises maintained outside, but supplemental vitamins and minerals once a month surely can't hurt.
Suitable quantities of vitamin A is also essential for eye and skin care. Insufficient quantities will cause puffy (even closed) eyes and flaking skin. This can be administered at the same time that the D3-calcium is given.
Continuing to add to the equation, an abundance of phosphorus or oxalic acid can negate the benefits of calcium additives. Foods containing oxalic acid (spinach, the leaves of wood sorrel) should not be fed to your chelonians and the ratio of calcium to phosphorus in a normal diet must be at least 2:1 in favor of the former. Charts showing the composition of foods are available on the Web.