Some playful hippos in the Zambezi.  They'd often slip under water and become
invisible, but if you rowed over them, they might pop up and tip you out (something
you didn't want to happen -- remember our crocodile friend).  The guide, Peter, would
keep his eye out for bubbles in the river -- a sure sign of a hidden hippo.  More than once,
we had to back paddle kind of quickly to avoid sweeping over those bubbles.

Note the mountains in the background.  That's Zambia, and you can see the pall of smoke
from all of the brushfires.