The African Spurred Tortoise (Geochelone sulcata) is also known as the ‘Grooved Tortoise’, the ‘Spur Tortoise’ and the ‘African Spur Thigh Tortoise’. It is a desert-dwelling tortoise whose range extends along the southern edge of the Sahara Desert from Senegal and Mauritania, east through Mali, Chad, the Sudan and Ethiopia to Eritrea. The African Spurred Tortoise is the third largest tortoise in the world and the largest mainland tortoise.
The other two largest tortoises that surpass it in size are the giant island species called the Aldabra Giant Tortoise (Geochelone gigantea) which resides on the islands of the Aldabra Atoll in the Seychelles and the Galapagos Tortoise (Geochelone nigra) found on the Galapagos Islands near Ecuador.
African Spurred Tortoise Description
The African Spurred Tortoise can measure up to 80 centimetres (2.63 feet) in length for the males and 50 centimetres (1.64 feet) in length for the females. Males weigh around 100 kilograms (220.75 pounds) and females 60 kilograms (132.45 pounds). Their carapace (the top shell) is light tan to brown in colour which gives it ample camouflage in their sandy environment. The carapace is quite flat and oval in shape and is deeply serrated between scutes (One of the large keratinous scales on the shell of a turtle or tortoise) which display prominent growth rings which develop with age.
Their plastron, head and limbs are uniform yellow/tan. Overlapping scales cover the front surface of their forelimbs (which assist in digging long burrows) and they have 2 – 3 conical spurs at the rear (from which their name derived). Their heads are relatively large and their upper jaw has a double hook. Tortoises also have very thick skin which helps restrict water loss.
African Spurred Tortoise Habitat
The African Spurred Tortoise lives in arid regions particularly desert and dry savanna and where there is no permanent water source. The African Spurred Tortoise digs burrows in the sand which can measure 30 – 35 inches deep or underground tunnels extending 10 feet or more. These burrows and tunnels give access to higher moisture levels in their arid environment. They spend the hottest parts of the day in these habitats. Permanent sleeping burrows are also constructed and are shared by two or more tortoises.
African Spurred Tortoise Diet
The African Spurred Tortoises are herbivores and their diet consists of desert succulents, dried leaves and grass and particularly leaves from the Morning-Glory plant.
African Spurred Tortoise Behaviour
Male African Spurred Tortoises are quite aggressive in nature and will ram and bite each other while vocalising grunts, croaks and whistles. Even from the moment these tortoises hatch they are aggressive with each other and even try to flip each other over on to their shells.
The African Spurred Tortoise becomes inactive during very cold or very hot weather. When long drought periods occur, they survive by bedding themselves into their burrows. Their most active periods are during the rain season (July to October) particularly at dawn and dusk when they will forage for food. They spend their mornings basking in the hot sun in order to raise their body temperatures which drop during the cold nights.
African Spurred Tortoise Reproduction
Mating occurs during the rain season, usually February to March. Males will fight for dominance over females and are vocal during mating. After a gestation period of 60 days, the female searches for a suitable nesting place. Many nests will be made before she chooses the most suitable one. Nests can measure up to 20 centimetres (8 inches) in width and depth and each one can take between 1 – 4 hours to construct. The female then begins to lay eggs every 3 minutes. Clutches may contain 15 – 30 eggs or more. The nests are then filled in and the eggs completely covered. Incubation lasts 212 days (around 8 months) and hatchlings emerge from the eggs 1 – 3 days after a rainfall, usually at night. It can take 3 – 10 days for the hatchlings to reach the surface of the nest.
Hatchlings are pale yellow and only 2 – 3 inches at birth, however, they can grow quite rapidly reaching 15 – 25 centimetres (6 – 10 inches) within the first few years. Like other tortoises, the African Spurred Tortoise can live to a great age. The oldest known species is 56 years old, however, the can live much longer and some can reach 80 – 100 years old.
African Spurred Tortoise Conservation Status
The African Spurred Tortoise is classed as Vulnerable by the IUCN. Habitat loss is one of the major reasons that numbers have declined mainly due to urbanisation and over grazing by domestic livestock. This species is also eaten by nomadic tribes and used to make longevity potions in Japan. They are also captured and kept as pets in Europe and North America. It is mostly young tortoises that are captured for trade and as it takes 15 years for them to reach maturity, it is very unlikely that they are able to reproduce themselves and therefore could face extinction.