Diet: Wild desert tortoises consume a high-fiber, moderate-protein, low-fat diet. Captive tortoises tend not to consume as much fiber as their wild counterparts because of the type and variety of foodstuffs offered to them. Mature tortoises should be allowed to graze in a grass-filled yard. This most closely resembles feeding habitats in the wild. Natural foods, such as grass, dandelions, clover, alfalfa hay, rose petals, and hibiscus and nasturtium flowers are preferred for captive desert tortoises. Spinach, broccoli, Swiss chard, alfalfa and bean sprouts, green beans, mixed vegetables, in addition to water-packed tuna and chicken meat, are good supplements. Various types of fruits can be offered, too. Avoid feeding products with a high fat content because excessive fat is undesirable and also becomes rancid quickly.
A completely natural diet (one that a wild tortoise would select for itself) can rarely be exactly duplicated in captivity. For this reason, and because the exact nutritional requirements of tortoises are unknown, vitamin-mineral supplementation is advised. Powdered supplements intended for reptiles (Reptical and Vita-Life, Terra-Fauna Products, Div. of G.M. Enterprises, Mountain View, CA 94042; Reptovite, Verners Pet Products, Long Beach, CA 90807) should be sprinkled over moistened food daily, so the powder adheres. We prefer the powdered vitamin-mineral-amino acid supplement Nekton-Rep (Nekton Products, W. Germany) and believe it to be superior to the other products listed above. Some foods should not be offered to captive tortoises because they are high in moisture (not in itself a detriment) and very low in nutritional value (lettuce of all varieties, cabbage, cucumbers, tomatoes, melons).
Tortoises seem to show a marked preference for these types of foods and will, if given the opportunity, feed on these to the exclusion of other food items offered at the same time. These foodsshould be offered in small amounts only on occasion as a treat, or not at all. Hatchlings are best started on expanded guinea pig chow pellets. Place the pellets in a shallow saucer and add just enough water to immerse them halfway. The pellets slowly absorb the water and expand, and then can be offered to the hatchlings. This should be the staple food to which grass clippings, clover, alfalfa and bean sprouts, dandelion flowers and leaves, and chopped mixed vegetables can be added. Lettuce and the other similar foods mentioned above should never be offered to hatchlings because of the likelihood that they become habit-forming, resulting in serious malnutrition.
Recommended Diets for Adults: Eighty percent of the diet should consist of wild grasses, dandelions (plant and flowers), clover, alfalfa hay, rose petals, and hibiscus and nasturtium flowers. Add vitamin-mineral powder to these ingredients daily. Twenty percent of the diet should consist of green beans, mixed vegetables, spinach, Swiss chard, alfalfa sprouts, and low-fat dry dog food, water-packed tuna, and diced/chopped chicken. Occasional treats can include melon, oranges and banana (of value because of moisture and vitamin content). Avoid lettuce of all varieties, cabbage, celery and cucumber.
Recommended Diets for Hatchlings: Eighty percent of the diet should consist of expanded guinea pig chow pellets, clover, dandelions (plant and flowers), wild grasses, fresh hay (grass, clover and/or alfalfa), rose petals, and hibiscus and nasturtium flowers. Supplement with chicken or tuna (packed in water). Add vitamin-mineral powder to these ingredients daily. Note: Guinea pig chow pellets plus some roughage with vitamin-mineral supplementation can be considered a complete diet. Twenty percent of the diet should consist of spinach, Swiss chard, chopped green beans and mixed vegetables, alfalfa and bean sprouts, and low-fat dry dog food (moistened). Avoid lettuce of all varieties and salad-type items composed mainly of water (cucumber, tomato, melons, etc.).