The Longest Lizard!!- Article by Gareth Jones

The Longest Lizard In The Nairobi National Park

After a cold day the sun finally came out giving some warmth. I drove down towards the Hyena dam, and I saw a fairly large monitor lizard, sunning itself on the side of the dam. It lay perfectly still, looking relaxed. I switched off my engine and watched for a while.

The monitor turned its head slowly and looked around, with its tongue flickering in and out. The lizard had interesting markings and I guessed it was about five feet long. After a while it must have determined that I was not a threat, as it moved away into the reeds. Wow! it is not every day that you see such a sighting, although monitor lizards are present into park, they are not often seen. They prefer to frequent aquatic areas like rivers and dams with plenty of bush and reed cover.

Recently we also observed some interesting behavior when a water monitor suddenly became visible next to the Athi dam. The water monitor was clearly hunting along the shores of the dam looking for bird eggs or young chicks. A crowned lapwing moved rapidly directly into the path of the water monitor lizard and pretended to have a broken wing as it frantically flapped its one wing while at the same time letting the other wing hang limp to the ground. This behavior known as the “broken wing”, is typical when such birds see a predator and they sense that their eggs or young are threatened, so the action is to deliberately lead the predator away from the eggs or young birds.

The species of monitor found in Kenya and many parts of Africa is called to Nile Monitor (Varanus niloticus). The Nile monitor is Africa’s longest lizard. They grow from about 120 to 220cm (3ft 11in to 7 ft 3in) in length, with the largest specimens attaining 244 cm (8ft). There is no denying that a bite from any species of monitor lizard can be downright painful. These are known to crush bones in humans. These are dangerous for skin, bone, and surrounding tissues. These lizards have the poisonous bite. The venom is not fatal for humans yet it can cause pain and illness.

Nile monitors are usually wary and if approached, will run away or jump into water, often from a considerable height. They are powerful swimmers. If cornered and threatened, a Nile monitor will arch its back and stand at full stretch on its legs, hissing as the body inflates and flicking the tail sideways. The lashing tail can inflict a painful wound. As a last resort a cornered Nile monitor will bite and eject foul-smelling musk from the cloaca to deter attack or throw off a pursuer.

Nile monitors feed on fish, snails, frogs, crocodile eggs and young snakes, birds, small mammals, large insects, and carrion. To me their most fascinating and amazing feature is their extra sense of smell. To do this they use their long forked tongue, and the reason it flickers in and out is so that the Lizard can “smell” the air. Monitor lizards, like snakes, have a pair of sensory organs located above the roof of the mouth called the Jacobson’s organs. The organs are used to detect scent particles within the air. These lizards continuously flick their forked tongues to collect these particles and to ‘taste’ the air; this extra sense is used mainly for hunting as monitor lizards are very active predators and are almost constantly foraging around for food. During the breeding season it is also used to help these usually solitary reptiles find a mate; the male will use his tongue to follow the scent of a female.

Nile (water) monitors also have incredibly powerful tails that they also use when hunting prey to strike. Large specimens have even broken the limbs of people who venture to close. Watch out for these large long lizards next time you visit the Nairobi park!

Hopefully many of you will be able to tell your own stories as you encounter more of the wonderful creatures we call reptiles. Take care!!!