Reliability and quality of artificial nectar feeders for birds in the Cape Floristic Region

Abstract

Supplementary feeding of birds may have considerable ecological and evolutionary effects on bird communities. However, there is a lack of basic information on the prevalence, frequency and quality of supplementary feeders, especially in African urban areas. Here we describe the prevalence, reliability and quality of artificial nectar feeders in suburbs in the Cape Floristic Region, South Africa, where many bird-pollinated plant species occur. Results from 291 questionnaires, completed by garden owners with an interest in birds, reveal that 57% of respondents have feeders in their gardens and 51% refill their feeders multiple times per week. The sugar concentration, total duration of feeding and frequency of feeding did not affect abundances or species richness of nectarivorous birds in gardens. We found a higher incidence of breeding sunbirds and sugarbirds in gardens with feeders than gardens without. Supplementary nectar feeding in this area has the potential to contribute to conserving nectarivorous birds, but investigation into the possible negative effects is needed.