The reason that the hippo is the most dangerous animal in Africa with
respect to human fatalities is simple. People in boats with out board
motors often tend to drive over hippos. The hippo tends to get a bit
shirty about this kind of behaviour and tries to chomp the boat in half
with it's powerful jaws. Usually the boat is at least capsised and often
destroyed (remember that hippos are gregarious and if the first hippo
doesn't get the boat the next one will). This means that the human
occupants of the boat have to avoid being chomped by the hippo and
succesfully swim through crocodile infested waters to the nearest shore.


Although hippos are very big, a hippo in the African night is almost
invisible. This means that people wandering home from the pub at night
may walk into one of them, startling it and possibly getting bitten/crushed
to death for their pains. Driving a car into a hippo at 60 miles an hour
also tends to be a low survival experience, for the occupants of the car
at any rate.


All of the above will be made doubly dangerous if the Hippo is defending
a calf at the time.