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The Nile Crocodile

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The Nile Crocodile The Nile crocodile The Nile crocodile or Crocodylus niloticus is an amazing creature and is certainly one of the daddies when it comes to the crocodilian world. It is certainly the stuff of myths and legends in Africa as well as being the source of numerous natural history programme’s which show these huge creatures seizing a zebra or gnu which is trying to cross a river. Geographically they range right across Africa from South Africa all the way up to Egypt. There are various localities where sub species have been suggested but not accepted yet. With all these areas the size of the crocodile average can vary. I personally observed Nile crocodiles on Lake Baringo in Kenya which don’t achieve lengths of more than about 4-5ft. Although the reasons for this are not totally understood, it is generally thought that the size of prey available is a contributory factor. Certainly in this particular location large prey is not available and the crocs survive on small mammals and fish from within the lake. The habitat of these creatures is also quite varied, from large open lakes to rivers as well as marsh areas with small water holes and pools. In all these areas this crocodile is totally at home. The Nile crocodile will adapt its habitat so it can bury and move out of any extreme weather changes that occur. Its appearance is substantial as it reaches five meters and sometimes even achieving six. Interestingly there is also some evidence to show that when a cooler country is occupied such as South Africa then the size of the individual decreases. Juvenile Nile crocodiles are brightly patterned with a black criss cross pattern and a dark olive brown skin. Crocodilians are unique in regard to the level of the intelligence which they show when compared to the rest of reptile world. It is accepted that they have a true cerebral cortex and are capable of learning behaviors and responses to given scenarios. They have also been observed in problem solving. I have observed a Nile crocodile climbing a four foot wall in exactly the weakest place. These reptiles are far from stupid and certainly should be given the respect they deserve. The temperament of this species can certainly be awesome but generally they are not as aggressive as their cousins the Saltwater Crocodile. In photographing these animals I have found that if you give them their own personal space then they have are not overtly aggressive. This however does not mean however that extreme caution should not be taken at all times. Certainly it has one of the widest diets of any predator for this vast continent. Juveniles will feed on aquatic invertebrates, small fish and freshwater crustaceans. As the juveniles continue to grow they will move on to water birds and small mammals which come to the waters edge to drink. As adults a large part of there diet can be scavenged from decaying bodies left in the river. It is not uncommon for hippos and other animals to fight and the loser be left dead and become food for crocs for miles around. The very large individuals will become braver and tackle any animal which ventures into the water, From Gnus to Water Buffalo and from Antelope to Zebra. All these animals are fair game to the adult Nile crocodile. Stealthy and sleek in the water, this predator is well known for attacking in as little as twelve inches of water, and without the drinking prey ever realizing the certain death which is approaching. One of the interesting points about this creature which is often treated as purely malevolent is the way that they can work together to feed more efficiently. These animals have been known to co ordinate fishing and also act as an anchor whilst other individuals tear pieces off a carcass. This helps the whole population within the area. Although feeding is always done with dominance in mind and weaker crocodiles will have to wait for the bigger ones to have their fill. What is truly amazing is to watch these animals drift along with the current making no wake. They come up upon their prey silently and without being seen. It is hard to imagine how you wouldn’t not notice a 15ft crocodile approaching you but this the demonstration of there guile and ambush. After gorging on a meal the Nile crocodile will use its thermoregulatory system to help digest its food. As well as basking on the bank of a river or lake the crocodile has ridges on its back called Osteoderms which have an increased circulation of blood and allow it warm up and cool down much faster. This feature will also allow it to hunt longer in the water by swimming with the Osteoderms above the surface allowing the sun to raise its body temperature. The breeding season will vary depending on locality and brings into play some of the gentler sides of this awesome creature. Along any river or lake will be a dominant male which has the rights over any females within his area. Sexual maturity will be reached in males at about three meters and females at 2.5. After copulation has taken place the female will begin digging a nest which is many meters from the bank. This is to try and allow for any rains which come when not expected. The location of this nest will possibly change if she is not totally happy or feel it has been disturbed. When the eggs are laid and placed in the nest the female will then guard it fiercely and chase off any predators such as monitor lizards or mongoose which would sniff out the eggs and have them as a tasty meal. There are no bounds to her ferocity during this period of time. After 80 – 90 days the eggs if all has gone well will begin to hatch. It has been observed that both the male and female will help in digging out the eggs and carrying the offspring to the waters edge whilst protecting them from any interested parties. It is amazing how gentle their jaws can be in accomplishing this task when you consider the same jaw is used in tearing off huge chunks from a prey item. The bite down force of an adult Nile crocodile is in the region of 3500 pounds and yet they can carry a 8 inch crocodile to the waters edge without any damage. Once in the water the juveniles will head straight for some cover and hide, these are their most dangerous times as most other animals will view them as food. Very quickly after the hatching the young crocs will begin to split up and head off in different directions and begin their new life as one of the greatest predators in Africa. .
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