African Landscapes from Southern Africa:Crocodiles and Lizards.
Have you seen a reptile lately?
There are five kinds of Reptiles: Amphisbaenas, Snakes, Tortoises, Lizards and Crocodiles found in Africa. South Africa has the most species of land tortoises in the world (13) and 130 species of snakes. In this article we will deal with the crocodiles and lizards as they are most commonly seen in the Game Reserves. We have seen quite a few snakes in the past and an article on them will have to wait for the future.
The only crocodile of the four species that occur in Africa found in Southern Africa is the Nile crocodile. Elsewhere in Africa Dwarf crocodile, Desert crocodile and narrow snouted Nile crocodile live in tropical areas. Crocodiles are also found in Asia, America (South and North) and Australia within the tropical areas. They are semi-aquatic and can exist in fresh, brack and even sea water. Crocodiles are carnivorous and feed on fish and a variety of vertebrae including large ungulates. As such it is considered an Apex predator, existing at the top of the food chain.
The large Nile crocodile that is found in Southern Africa is almost extinct outside reserves. In most of the game reserves groups of crocodile can be seen sunning themselves on the banks of rivers and dams, indicating their social nature. Often they are also seen lying in the water or swimming slowly just under the surface keeping a careful eye out for a meal. There are many “Crocodile Farms” in the country where visitors can look at these menacing animals from the safety of a viewing area.
Crocodile products include shoes, handbags, belts and even steaks. Items made from crocodile skin are sought out for their durability and softness. In some tribal areas the skin is used for religious purposes. In some areas where crocodiles still exist in the wild in rivers they are a danger to local people who go to those rivers to fetch water. A recent incident in the St Lucia Estuary ended in tragedy for a local subsistence fisher woman who was taken by a crocodile as she stood in the shallow water. Her family tried to rescue her using their fishing rods but failed to do so. Warnings along rivers and dams in game reserves often warn against the danger of these dangerous predators with their powerful jaws.
Crocodiles can move surprisingly quickly for their size, both in water and on land. Their swimming speed has been measured at 25 km/hour. They can live to over a hundred years and can weigh over 1000 kg and grow to over 6m in length. They breed by laying eggs in a hole in the ground. Their bite is exceedingly strong but the muscles used to open their mouth are weak and so they can be controlled by holding/tying their mouth closed. (Not recommended to be tried at home!)
The other member of the reptile family that you are bound to see on a visit to the game reserves in Southern Africa is the lizard. They will often be spotted sunning themselves on rocks or melting in with the background colour of the bark of a tree. They often have large feet and toes that enable them to climb vertical cliffs and tree branches. They are insectivorous except for the monitors who feed also on small birds. None of them are poisonous and they rely on stealth to capture their prey. They often use their long tongues to catch their food.
There are 250 species of lizard in Southern Africa and include chameleons, agamas, geckos and monitors. These animals can adapt to different environments and so are often found in desert and semi-desert conditions. Because they are masters of disguise they often surprise you if you look carefully at a tree or rock. They do not move a lot as they stealthily wait for their prey to come close enough to grab. When the food/insect is close enough they pounce with amazing speed, often too fast for the human eye to see.
A visit to the game reserves in Southern Africa is certain to produce views of the largest reptile, the Nile crocodile and a variety of lizards. In visiting the drier regions you are likely to see a couple of tortoise and even the occasional snake. On a visit to the Kruger National Park we were fortunate enough to see a long green snake swimming across a river only to be met halfway by a splash, as it was taken by surprise by a crocodile that had been watching it enter his environment, and so became a crocodile snack.
Sources: The Wildlife of Southern Africa: Vincent Carruthers