In Biggles Hunts Big Game, Kolo was an African employee of the Kudinga hunting lodge ran by the Stellar Skyways criminal gang.
When the search party led by Kreeze and John Robinson found the bodies of Kisumo and Bertie, Kreeze found the discovery very convenient as he could photograph the bodies as proof that they had died as the result of a hunting accident, Kisumo having been killed by a raging bull and Bertie having been accidentally shot by Kisumo. This, however, had to wait for daylight, and so, to prevent hyenas from disturbing the scene, Kreeze detailed Kolo and two others to stand guard until daybreak.
Bertie was, of course, only feigning being dead. Ginger was hiding nearby and wanted to get rid of Kolo and his fellow guards so that he and Bertie could continue their investigations. So Ginger mimicked a lion's roar. This succeeded only too well. Kolo, who was reluctant to spend the night in the jungle in the first place, was frightened out of his wits and fled with his colleagues.