Tortoises are land dwelling turtles from various parts of the world; they are variable in size and habitat requirements. Most tortoises sold today were raised in captivity. They tend to be mild mannered and shy. Tortoises are not native to Oregon and do not survive long term if released here. Some, like Sulcata tortoises, become very large and require a tropical environment, making them difficult to care for in the Pacific Northwest. Others, such as Russian tortoises, are small and have more temperate habitat requirements, making them easier pets. When you obtain a "wild pet" you must try to duplicate that animal’s natural conditions.
Tortoises are slow moving and can’t chase fast prey. Their diet is mostly vegetables, especially leafy greens, but they may occasionally eat invertebrates. A good simple diet would be 85%-95% vegetables & fruit, and 5%-15% tortoise food. Vegetables should include leafy greens such as spinach, collards, kale, and dandelions; avoid iceberg lettuce as it is nutritionally poor. Fruits can be used sparingly. Ideally use a nutritional guide to choose veggies with good calcium content. Variety helps minimize risk of nutritional deficiencies; ideally the turtle should regularly eat at least 8-10 different vegies and fruits. Various dry and canned tortoise diets are available; the best are probably the pelleted foods which are bright colored and smell fruity. Pretty Pets is one of the more palatable brands; T Rex is similar. The pellets can be offered dry, or softened with water, or crushed and sprinkled on dampened vegies as a powder daily. A diet which includes a good variety of vegies and commercial food is complete and balanced, and does not need additional supplementation. Avoid high protein foods such as meats, dog food, cat food or monkey chow as these may harm the turtle.
If you can’t use a commercial tortoise diet, then protein and vitamins need to be provided in other ways, although achieving a good nutritional balance is more difficult. Protein sources include tofu, beans (various types), silkworms, earthworms (use nightcrawlers, not redworms or compost worms), and slugs. Minimize crickets & mealworms. Protein sources should always be used sparingly, as less than 5% of the total food intake. Without a tortoise food, vitamins & minerals should be provided via a single powdered multivitamin-mineral supplement such as Reptocal or Reptivite; use a tiny pinch on the food once weekly, no more. Overdosing is easy with supplements, and some products are toxic; it is safer to use a commercial diet which has a balanced supplement included.
Water should be provided at all times. Use a small low bowl which is too heavy to easily tip over; a ceramic ashtray is adequate. Ideally the bowl should be small enough to prevent the tortoise from soaking and defecating in the water. Baths are unnecessary, but if elected they should be done in a separate container with very shallow warm water and should be brief (20-30 minutes maximum). Some tortoises may drink very little, preferring to obtain their water from the vegetables they eat.
A terrarium is usually needed to provide good housing, although the turtle can exercise in the house daily (up to 30 minute intervals). The terrarium walls and top should be mostly solid, not screen, to trap heat & humidity. A minimum size would be 3¾ to 4 square feet of floor space for a small tortoise (equivalent to an 18 x 30 inch or 24 x 24 inch enclosure.) Cage height is less important as the turtle lives on the cage bottom. (Large tortoises may need several hundred square feet or more of living space, requiring large habitat setups). Artificial turf makes good flooring as it can be cleaned and reused, and it can’t be eaten. Sand, gravel, corn cob, wood chips, etc may be eaten and cause bowel blockages; if used they must be changed regularly when soiled. Air temperature (measured in the shade) should be 75°-85°F in the day for temperate species, 80°-95°F for tropical species, and ideally at least 70°F even at night. Use a good mercury or dial-type thermometer which can be moved to check temperature in various locations at the cage bottom; avoid color strip thermometers which stick on the cage wall as these are inaccurate. A reptile heat pad beneath the cage is one heating method; hot rocks can be used but should be covered (with turf or other rocks) to prevent burns from direct contact. Heat lamps inside the cage should be at least 18 inches above the turtle to prevent burns. Heat lamps used at night should produce minimal light; lightless ceramic-coated bulbs, dim purple or red night lights can be used. Tortoises are shy and the cage should be in a quiet area. They need hiding places to feel secure, but you should try to avoid using dark caves or hiding boxes which block exposure to UV light. Instead provide objects such as plants or rocks to hide behind, or use paper to cover the cage glass in one corner, creating a private area which remains well lighted.
Lighting should be provided 12-14 hours daily, with the remainder being dark. You must provide white (visible) light and ultraviolet light in the 280-320 nm wavelengths (called UV-B). This mimics basking in the open sunlight. Our climate provides too little sun, and window glass or plexiglass filters out most of the UV light, so you need to provide sunlight artificially. The simplest lighting is fluorescent full spectrum bulbs; incandescent "screw type" round bulbs are not adequate. Some good brands include Reptisun by Zoomed, and Reptile D-Light. Other bulbs which produce less UV but are adequate include Verilux, Reptasun by Flukers, Reptiglo, Reptile Daylight by Energy Savers Unlimited (ESU), and Vita Lite by Durotest. These bulbs won’t burn the pet and need to be close to the turtle to be effective; in general the maximum effective distance is less than the bulb length. For instance, a common 24 inch tube should be within 18 inches of the turtle. Avoid glass or plastic barriers between the bulb and the pet as these block the UV light. Change these bulbs every 6-8 months when in use as they produce less UV light over time.
NOTE: More recently a few incandescent "screw type" round bulbs have appeared which do produce UV-B; these look like typical bulbs but are actually mercury vapor lamps. They produce both UV and strong heat, so should be kept at least 18 inches from the turtle. Their effective lifespan is uncertain. These devices cost $45-100 and when turned off must have a "cool down" period before they can be restarted. Incandescent bulbs which cost less and do not require a cool down period are simple filament-type bulbs and do not produce adequate UV-B.
Cool climate tortoises may be allowed to hibernate in the winter in an unheated garage or greenhouse; the temperature needs to be below 55°F ideally, and day length should be short (winter hours). Hibernation can be difficult to achieve, and you may elect to keep a turtle active in the winter. Never hibernate a sick turtle.