MARKED DIETARY DIFFERENCES BETWEEN SYMPATRIC FERAL ROCK DOVES AND ROCK PIGEONS

Although feral rock doves Columba livia and rock pigeons C. guinea fly daily in mixed flocks between roosting and nesting sites in Cape Town , South Africa, they feed separately in farmlands north of the city du ring the austral summer. Examination of the crop contents of 32 feral rock doves and 48 rock pigeons revealed that 28 (88%) of the feral roc k doves had fed on processed cereals, whereas all 48 (100%) of the roc k pigeons had eaten whole wheat. The processed cereals were obtained f rom dairy cattle feedlots, whereas the whole wheat is waste, found wit hin the stubble. There is equal nutritional advantage from feeding on both food types, and feral rock doves have no apparent preference for either food type. This differential feeding behaviour suggests resourc e partitioning, and that introduced feral rock doves do not displace i ndigenous rock pigeons from summer food sources in the south-western C ape Province.