Most tortoises are herbivores, but a few species are genuine omnivores that regularly eat insects, carrion, and other animal matter in the wild. The answer depends entirely on which species you’re talking about. The majority of pet tortoise species thrive on a plant-based diet rich in fiber, and feeding them animal protein can cause serious health problems. A smaller group, most famously the red-footed tortoise, naturally supplements its plant diet with animal-based foods and needs that variety to stay healthy.
Which Species Are Herbivores and Which Are Omnivores
The large majority of land tortoises are strict herbivores. This includes some of the most commonly kept species: sulcata (African spurred) tortoises, Hermann’s tortoises, Greek tortoises, Russian tortoises, Indian star tortoises, and leopard tortoises. In the wild, these animals eat grasses, weeds, flowers, and leafy plants almost exclusively. Their digestive systems are built around breaking down tough, fibrous plant material.
The well-known omnivorous tortoises are the red-footed tortoise and the yellow-footed tortoise, both native to South America. Field observations of wild red-footed tortoises have documented them eating live and dead foliage, fungi, insects, and animal matter. They’re also opportunistic scavengers. Researchers have recovered bone fragments from the droppings of wild individuals, and direct observations confirm they eat carrion when they find it. Despite this varied diet, red-footed tortoises still show a strong preference for fruit.
No tortoise species is truly carnivorous. The dietary spectrum runs from strictly herbivorous to omnivorous, never to meat-dependent.
Even Herbivorous Tortoises Sometimes Eat Meat
Wild tortoises that are classified as herbivores will occasionally eat animal matter when the opportunity presents itself. In one remarkable case, a female Seychelles giant tortoise was filmed deliberately pursuing a noddy tern chick along a log, extending her neck, and killing the bird with a single bite before swallowing it whole. This was the first documented instance of deliberate hunting in any tortoise species. Other tortoises on the same island have been observed engaging in similar behavior, apparently targeting chicks that fall from nests and can’t escape.
These incidents are rare and opportunistic, not a regular part of the diet. They suggest that tortoises aren’t as rigidly herbivorous as once assumed, but they don’t change the dietary recommendations for captive care. A Seychelles giant tortoise or a sulcata that stumbles on a dead insect in the yard isn’t doing itself any harm, but it doesn’t need animal protein offered as food.
Why Fiber Matters More Than Protein for Most Tortoises
Herbivorous tortoises rely on a process called hindgut fermentation to extract nutrients from their food. Instead of breaking down food primarily in the stomach, they depend on communities of microorganisms living in their large intestine to ferment plant fiber and produce usable energy. These gut microbes need fiber as their primary fuel source. Without enough of it, the whole system slows down.
For grassland species like the sulcata, fiber typically makes up 75 to 85 percent of the natural diet. Hatchlings need slightly less, around 65 to 75 percent, favoring tender grass shoots and softer weeds. In the wild, herbivorous tortoises eat diets that contain over 20 percent crude fiber and only about 10 to 15 percent crude protein on a dry matter basis. Commercial tortoise pellets designed for herbivorous species should reflect those same proportions: roughly 10 percent protein and at least 20 percent crude fiber.
This is a dramatically different nutritional profile from what most people assume a pet needs. If you’re feeding a sulcata or a Hermann’s tortoise the same way you’d feed a red-footed tortoise, with fruit, higher protein, and less fiber, you’re working against the animal’s biology.
What Happens When Herbivorous Tortoises Get Too Much Protein
One of the most visible consequences of an inappropriate diet is shell pyramiding, where the individual scutes on the shell grow upward into raised, bumpy pyramids instead of lying flat. A study on African spurred tortoise hatchlings tested three protein levels (14, 19, and 30 percent crude protein) and found that higher dietary protein had a minor but measurable positive effect on pyramidal growth. Environmental humidity played a larger role, but protein contributed. Blood tests for calcium, phosphorus, and other markers didn’t explain the shell changes, suggesting the mechanism is more complex than a single nutrient imbalance.
Beyond the shell, excess protein in herbivorous tortoises stresses the kidneys. These animals aren’t equipped to process large amounts of nitrogen waste from protein metabolism. Over years, this can contribute to kidney damage, gout, and a shortened lifespan. The effects are gradual and often invisible until they become severe.
Calcium and Vitamin A: Two Nutrients Worth Watching
Regardless of whether a tortoise is herbivorous or omnivorous, calcium is critical. The ideal ratio of calcium to phosphorus in a reptile diet is often cited as somewhere between 1:1 and 2:1, but wild Greek tortoises actually eat a diet closer to 4:1 or 5:1 calcium to phosphorus. The practical takeaway is to aim for at least a 1:1 ratio, and ideally higher. Foods high in phosphorus relative to calcium (like most fruit) should make up a small portion of the diet for herbivorous species. Calcium supplementation, usually in the form of a light dusting on food, helps close the gap.
Vitamin A deficiency is another common problem, particularly in chelonians that don’t get enough dark leafy greens or orange and yellow vegetables. Signs include swollen or puffy eyes, decreased appetite, dry or flaking skin, runny nose, and general lethargy. Dark greens like dandelion leaves, pak choi, and broccoli are good dietary sources, as are orange vegetables like squash, carrots, and sweet potato. For herbivorous tortoises, a varied rotation of these plants usually prevents deficiency without supplementation.
Feeding Guidelines by Category
For herbivorous species (sulcata, Hermann’s, Greek, Russian, leopard, Indian star), the diet should center on:
- Grasses and hay: the bulk of the diet, providing the high fiber these species need
- Weeds and leafy greens: dandelion greens, plantain weed, clover, and other broadleaf plants
- Vegetables: squash, shredded carrot, and other high-fiber options in smaller amounts
- Fruit: rarely or not at all for most herbivorous species, as the sugar content is too high
For omnivorous species (red-footed, yellow-footed), the diet should include everything above plus:
- Fruit: a regular but not dominant part of the diet, reflecting their natural preference
- Animal protein: small amounts of insects, earthworms, or commercially available low-fat protein sources offered occasionally
- Mushrooms and fungi: which red-footed tortoises consume in the wild
The core mistake most tortoise owners make is treating all species the same. A red-footed tortoise that never gets animal protein is being underfed nutritionally. A sulcata that gets regular animal protein is being slowly harmed. Knowing which category your species falls into is the single most important dietary decision you’ll make for the animal.