Indirect effects of livestock and native herbivores on food web interactions, other than resource competition, have rarely been studied. One such pathway is that in which large ungulate herbivores both directly and indirectly impact the reproductive structures of plant species, which in turn can affect floral visitors of those plants. Natural studies on large herbivores and their indirect effects on floral visitors are almost completely lacking. We examined how native herbivores and cattle indirectly affect the abundance of a dominant butterfly guild, Colotis spp., at a set of long-term exclosure plots in an acacia savanna in central Kenya. Colotis spp. are specialized feeders on Cadaba spp., a common shrub genus. We counted flowers on randomly chosen Cadaba bushes in each plot, conducted multiple butterfly counts, including non-Colotis butterflies, within each plot, and averaged those counts together to get per plot flower numbers and butterfly abundances.

Results/Conclusions

We expected that, in plots from which wildlife had been excluded, there would greater flower production and increased densities of floral-visiting butterflies. Across the experimental plots, Cadaba farinosa flower numbers were positively correlated with Colotis abundances, and both were suppressed by the presence of wildlife herbivores. However, the abundances of Cadaba flowers and Colotis butterflies were greatest in plots with cattle herbivory, not in total large herbivore exclusion plots. Our results suggest that well-managed cattle herbivory may benefit diverse taxa and that domesticated livestock can coexist with wildlife and still maintain diversity and fitness of species from multiple taxa.