Crocodile Dundee in Zimbabwe

Cocoon-Like Eggs

When the long metal spike cracks open a fragile egg, grains of sand stick to the metal tip as it is pulled back through the sand. This telltale sign is followed by furious digging, using the method a dog would to look for its lost bone. The carefully hidden nest reveals 30 to 60 cylindrical, cocoon-like, white eggs with a fine, plastic-like, granular surface, not much bigger than a double yoked chicken's egg.

Occasionally a nest will have already been vandalised by local fishermen, who would rather see less crocs in the lake, or has been raided by monitor lizards (leguaans), or baboons which crave such delicacies. Unlike these messy intruders, the egg-collecting crew always leaves the nest exactly as it finds it, to minimise disturbance.

Incubation Temperature Determines Sex

The eggs are incredibly sensitive. If an egg is turned upside down it will die. The top of each one is therefore gently marked with pencil as it is lifted from the nest. They are carefully packed in polystyrene boxes and transported to the farm's incubators to sit cosily for up to 90 days before hatching.

The extreme sensitivity of the eggs is such that the incubation temperature actually determines the sex of the crocodile. This bizarre freak of nature produces 80% males at a constant 33°C and 80% females at 32°C.

To ensure the stability of the wild population, crocodile farms are obliged to return 2% of the hatchlings to Lake Kariba at six months old at an average length of 75cm. These crocodiles are bigger than their naturally hatched counterparts - 95% of which never make it to that age - and have a much better chance of survival.

Crocodiles the size of small islands can be seen cruising the shallows of Lake Kariba or basking in the sun on rocks. The males are extremely territorial and fight to the death, defending their patch against lone adult males looking to stake their claim. Fortunately the females and juvenile males are allowed to pass freely through the territory. Not so for the unfortunate hatchlings which make a tasty meal.

'The Submarine'

A renowned crocodile known as 'the Submarine', whose unchallenged domain lies at the western end of the lake near Mlibizi, regularly sneaks up and takes cows grazing unsuspectingly on the riverbank. Losing a cow is nothing to losing a family member and Kariba crocodiles have become dangerously partial to local villagers and wading fishermen. Local newspapers report missing persons on a far too regular basis.