The spittle bug is a nymph of a small insect called a froghopper. They occur in large colonies on the branches of certain trees. Spittle bugs pierce the bark with their stylets to suck out the sap at great speed. They filter out the nutrients, excreting the almost pure excess water as a protective froth against the sun which would otherwise dry them out. As the spittle bugs eject the almost pure water equally fast, it drips from the tree like rain. The froth is also a guard against birds, as they don't like its taste.
The mopane worm is the caterpillar of the large emperor moth. During December and January enormous numbers of mopane worms feed on the leaves of the mopane trees in Kruger Park.
Mopane worms are considered a delicacy by local inhabitants, who collect millions of them in areas adjoining the Kruger Park. They spread the mopane worms in the sun to dry and then either sell them or eat them. It is estimated that during these annual outbreaks, the mopane worms eat more mopane leaf-material than elephants in the same area.
