Sulcata tortoises are found in North Africa along the southern edge of the Sahara, from Senegal and Mauritania east through Mali, Niger, Chad, the Sudan, Ethiopia, and along the Red Sea in Eritrea.
Sulcata tortoises live in hot, arid or semi-arid environments. These areas range from desert fringes to dry savannahs. Standing water is only available for limited amounts of time. Urbanization, domestic animal grazing, and desertification have disturbed much of the sulcata tortoise’s range.
Sulcata tortoises are herbivores, eating succulent plants not just for food but also for their water needs.
Sulcata tortoises are the largest of the African mainland tortoises with males reaching weights of over 200 pounds while females usually do not get much larger than 100 pounds. Only the Galapagos and aldabra tortoises are larger.
Male sulcata tortoises reach sexual maturity when their carapace (top shell) is about 14 inches in diameter. Male sulcatas are very aggressive toward each other, especially during breeding time. The males ram each other repeatedly, sometimes resulting in bloody limbs and heads. Copulation can take place anytime from June through March but occurs most frequently after a rainy season in September through November. Nesting season is in the autumn when the female digs out a depression in the sand and then urinates in it in preparation of laying her eggs. She digs until the depression reaches approximately two feet in diameter and 3 to 6 inches deep and may take her up to five hours to dig. Four or five nests may be dug before she finally selects one to lay her eggs in. Once she selects a good hole, an egg is laid every three minutes. Her clutch size may reach 15 – 30 eggs, sometimes more. The eggs are white and spherical with brittle shells. After the eggs are laid, the female will fill in her nest, covering her eggs with sand. The eggs incubate underground for about eight months. When they hatch, the tortoise’s carapace is only 1.5 to 2 inches in length. They are oval-shaped and weigh less than 25 gm.
Sulcatas are very aggressive towards each other. Ramming into each other and attempting to flip each other over are common behaviors by males. Sulcatas like to burrow and are well adapted at doing it. They are very strong and active tortoises but when the weather gets too hot or too cold for them, they retreat to a burrow. This also helps them to avoid dehydration, since they depend mainly on metabolic water and the moisture in food for water. They will stay in their burrow for hours and if mud is available, they will flip it onto their backs. When temperatures reach more than 104 F, they salivate and smear the saliva on their forearms to help with cooling. Sulcata tortoises are most active at dusk or dawn and generally bask in the morning to raise their body temperature after the chill of the night.
IUCN Red List: Vulnerable.
US Federal List: No special status.
CITES: Appendix II.
Many populations of sulcata tortoises are rapidly disappearing, especially in Mali, Chad, Niger, and Ethiopia. In Senegal there are still limited populations in the north and north-east, but there is a lot of overgrazing and desertification that is wiping this tortoise out.
Some African cultures regard sulcata tortoises as a mediator between men and the gods. As a result, the tortoise is often kept in villages to intercede between the head of the village and the ancestors. In Dogon countries today, the tortoise is kept with the village leader at all times to allow him to communicate with the village ancestors. In Senegal, the sulcata tortoise is a sign of virtue, happiness, fertility, and longevity. Because of this perception of sulcata tortoises it is easier to promote programs that support the conservation of them. The Senegalese respect the symbolic nature of the tortoise and are very important in helping conservationists ensure reproduction and repopulation of it.
Harrold, A. 2001. “Geochelone sulcata” (On-line), Animal Diversity Web. Accessed December 15, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Geochelone_sulcata.html.