Looking deeper into African spurred tortoise diet

Like most Fossil Rim Wildlife Center animals, African spurred tortoises are vegetarians. In the wild, these tortoises graze on a variety of wild grasses, succulents and flowers found throughout the Saharan regions of North Africa. When the vegetation conditions are just right, these tortoises will graze for hours on end and are often considered voracious eaters.

Here at Fossil Rim, we try to mimic these foraging opportunities in captivity. Our tortoises have lush green yards to graze in and are provided additional trays of food three times a week, as we vary which grasses, leaves, flowers and succulents they get. Some plants and flowers will vary seasonally, but we also collect and freeze greens for the winter season when green vegetation is scarcer.

African spurred tortoises normally select a high-fiber, low-water content meal that favors their gut bacteria to break down food items via fermentation for increased nutrient absorption. Our African spurred tortoises are offered a tray of approximately 75-percent fresh plants and 25-percent succulents at each feeding.

Some of the succulents our tortoises consistently get and enjoy include spineless prickly pear cactus, aloe and agave. These are high in fiber just like the tough desert plants they consume in the wild. Plants and dark leafy greens our African spurred tortoises like to graze on include Bermuda grass, hay, grapevine leaves, small amounts of collard greens and mustard greens, as well as weeds like henbit, chickweed and dandelions.

Tortoises are only sparingly provided store-bought lettuce, which is high in water and lower in nutrients. They are offered certain greens such as kale, parsley and spinach on occasion. These greens tend to be high in either calcium oxalates (calcium-binding minerals) or goitrogens (substances that disrupt the thyroid gland’s hormone production), which can cause calcium/phosphorus imbalances and cause goiters (enlarged thyroid) to form.

In general, tortoises need the correct ratio of calcium to phosphorous in their diet. A diet with calcium/phosphorus imbalance may lead to urinary stone formation and metabolic bone disease. All plants that we collect onsite at Fossil Rim are chemical-free, ensuring that our animals do not ingest any herbicides, pesticides and fertilizer.

Many tortoises cannot digest fruits well due to their high water and sugar content that can decrease a tortoise’s gut bacteria productivity by altering the pH of the digestive tract. One fruit we can provide to our tortoises, and perhaps one of their favorite treats, is the red spineless prickly pear cactus fruit, which has much less sugar than most other fruit. Our tortoises also get occasional diet treats such as pumpkin, carrots and yellow squash.

African spurred tortoises must get calcium in their diet for healthy muscles, bone and eggshell production. Some calcium in their diet comes from the plant materials they eat, such as dandelion greens. We also like to include a dusting of cuttlebone powder to the top of their prepared diets for a calcium boost.

-Children’s Animal Center Intern Kayla Rupper & Children’s Animal Center Supervisor Kristina Borgstrom