Reptiles are cold-blooded (ectothermic), scale covered creatures which occur all over the world with the exception of the Antarctic. The class Reptilia consists of four different orders, of which three can be found at Sabi Sabi: Squamata (snakes and lizards), Crocodylia (crocodiles) and Testudines (tortoises, terrapins and turtles). The fourth order of reptiles exists only in New Zealand. We tend to see more reptiles at Sabi Sabi during our summer months (October to March) because of the fact that the reptiles’ metabolisms slow down and they become less active as the ambient temperatures drop.
Whatever the classification, reptiles have many more shared characteristics than those listed above.
They are air-breathing with fully developed lungs; they are tetrapods; and have, or are descended from predecessors with four limbs. They smell by means of a vomeronasal organ on their palates called the Jacobsons organ.
Reptiles are generally oviparous (reproduce by laying shelled eggs), although some species of lizards and snakes (such as the puff adder which is found at Sabi Sabi) are viviparous – giving birth to live young.
The growth rate of most reptiles is determined by temperature, food availability and food quality. Whatever the rate though, they will all shed their skin as they get older and larger.
Listed below are four species of reptiles found at Sabi Sabi:
Tree Agamas (Squamata)
Tree Agamas are a fairly large, spiny species. They are strictly diurnal, insectivorous lizards which rely on camouflage – colour blending into their environment as a means of protection from predators. When they perceive danger they will move around the tree trunk and flee into the upper branches. In mating season the Southern Tree Agama male’s head can become intensely blue.
The two species of tortoise found at Sabi Sabi are the Leopard Tortoise and the Speke’s Hinged Tortoise. The Leopard tortoise ( Stigmochelys pardalis) is the largest tortoise in southern Africa reaching a weight of up to 40kgs. This very attractive tortoise has a lifespan of 80 years.
Both of these tortoises are diurnal herbivores with well-developed bony shells to protect their bodies. They are not territorial but can have home ranges of more than 80ha. Their diet consists of a variety of plants, including succulents, grass shoots and fallen fruit. Old bones and carnivore faeces are also consumed, which may be a way for them to add necessary calcium into their diets.
Flap Neck Chameleon (Squamata)
The Flap Neck Chameleon is the only species of chameleon found in the Lowveld region of South Africa. They are slow moving creatures, with eyes which can move independently and feet which are adapted to enable the chameleons to cling onto vegetation.
They have strong prehensile tails of equal length to their bodies – which can be up to 15cm long. At rest these chameleons are usually emerald green, but they have the ability to change colour and when stressed their skin changes to almost black or several shades of green, yellow and brown.
Southern African Python
Pythons are distributed throughout sub-Saharan Africa, south and south-east Asia and Australia.
The Southern African Python is a strong, muscular snake and is by far the largest snake in South Africa, reaching a maximum length of 5 meters and mass of 60kg. Once a python attains a length of about 4.5 meters – close to its length limit, the snake becomes massively thick. Most snakes, like the python, don’t ever stop growing; their growth just slows down as they get older. The rate of growth of snakes is dependent mainly on temperature and food availability.
Southern African Pythons are predominantly active at night and can be seen basking in the morning sun, especially during the colder winter months. In the case where water is close by, the python may choose to take refuge in the water. Like most other python species, the Southern African Pythons have very distinctive triangular heads with moderate size eyes and vertical pupils. Their bodies are usually dark brown with grey-brown blotches and speckles.
Pythons are ambush hunters and prefer to use animal pathways or water bodies to patiently wait for their prey to pass by. They are not venomous snakes – they kill their prey by constriction. Pythons prefer warm blooded prey and recorded species include a variety of birds and mammals such as grey duiker, impala, nyala, vervet monkeys, African wild dog and cheetah.
It can take a Southern African Python up to 10 years to become sexually mature. Mating happens between June and September, with eggs being laid between October and December. The females become more active during the mating season and leave scent trails for the males to follow. It is not unusual to find up to 13 males attending to 1 female. Strangely enough there is no aggression or rivalry between the males during this mating ceremony.
Depending on the size and age of the female, this python species can lay between 30 and 60 eggs – usually in termite mounds or in aardvark burrows. Python eggs appear to be sensitive to temperature and the female will curl herself around the eggs to keep them warm. Very few reptiles are known to attend to their young as they hatch but the Southern African Python is the exception. The females actively attend to their eggs until they hatch and have been recorded staying with the young for up to two weeks after hatching. The hatchlings, which measure between 500 – 700mm and weigh about 100g, shed their skin roughly 12 days after hatching and will disperse a day or two later.
The Southern African Python is listed as “vulnerable” in the most recent South African Red data book due to habitat destruction and being hunted for food.