Southern Red-Billed Hornbill

This is a bird I know very well, a Southern Red-Billed Hornbill, Tockus rufirostris.  These are common over here, especially in the Kruger National Park.  At about 38-43 cm/15"-17" in overall length, it is small for a hornbill and has one of the smallest bills in the group also.  The red-billed hornbill group was once considered a single species, but has now been split into 5 quite similar species, ranging from Senegal and Gambia in northwest (sub-Saharan) Africa, to East Africa and down to South Africa.  Like other species, the females of this one spend time 'imprisoned' in a hollow tree or stump, with the exit hole sealed up with mud leaving only a slit for the male to feed them through, as they hatch their eggs and raise their chicks.  Watercolour.