The name duiker derives from the Dutch word for diving. A reference to the animals tendency to bolt for cover at the first sign of danger. It is an appropriate name for when one comes across them walking in the bush, this is generally what they will do if they see you before you see them. (And they usually do see you first, on account of our loud clumsy feet giving good warning of any approach.)
Last night I spotted a common duiker (Sylvicapra grimmia subsp. grimmia) as I walked to the window. However, it spotted me at the same time and our encounter was brief. In contrast, early this morning I was fortunate to spy this pair of common duikers before they saw me. They were grazing the grass outside our house and nibbling on the shrubs. They seemed unperturbed by how close they were to human habitation and continued browsing as long as I stayed still enough. Eventually they wandered off into the surrounding bush, but I am sure they will be back.
December 2015 update: We have continued to see common duiker on and off throughout the year in the reserve but interestingly a year on from the first sightings, the duikers are back on our lawn again. We now have a little video clip of them browsing just outside our window.