Seed augmentation has a limited effect on species diversity of sand-dwelling ants

Abstract

*[We examined the effect of artificial seed augmentation on the diversity of seed-eating ant species at the Mash'abim Sands Nature Reserve in the Negev Desert in Israel. In a 2-year experiment, the foraging activity of the different ant species was observed at 2-month intervals, during both night & day, in 9 plots that were enriched daily with millet & sunflower seeds. Each plot was divided into 20 stations. The 9 plots were randomly assigned to each of 3 seed-enrichment treatments: no seed addition (control), addition of seeds that were available only for ants, or addition of seeds that were available for both ants & rodents. Eight seed-eating ant species were observed at the baits, 3 of which were specialist seed-eaters (Messor aegyptiacus, Messor arenarius, Messor ebeninus), & the other 5 were generalist species (Crematogaster inermis, Monomorium salomonis, Monomorium pharaonis, Pheidole pallidula, Temnothorax arenarius). Most of these species were observed in all treatments. The results reveal no significant effect of seed augmentation on ant species diversity. However, there was a trend of increase in diversity in the ant-only compared to the control plots during the day. This increase contradicts the hypothesis that seed-enrichment in deserts would lead to decreased ant species diversity due to increased inter-specific or inter-taxon competition due to increased territoriality of either the dominant ant or rodent species, respectively.]