South Africa’s endemic fauna and flora is threatened by an increasing number of invasive alien species, such as the notorious Argentine ant (Linepithema humile). This ant species threatens not only the native ants’ community structure, but also the vital ecosystem services native ants provide. This study explores the seed dispersal ability of invasive and native ant communities, along with the seed traits that underpin this mutualism. We use of seed-choice experiments and comparative seed-trait analyses to determine the influence of ant community structure on seed dispersal success of a range of native fynbos and invasive Acacia plant species. Three distinct ant communities were identified in this study. The ant community invaded by L. humile preferentially dispersed small-seeded invasive Acacia seeds over that of the native plant species. The native communities (dominated by the ant Anoplolepis sp.) showed a preference for large-seeded native species, with the lowest removal rates recorded for Acacia plant species. Preliminary analyses of the seed traits reveals this preference to be driven by several factors, including: seed and elaiosome size, as well as the total content and abundance of two key fatty acid compounds. In conclusion, the invasion of L. humile is likely to facilitate the invasion of Acacia plants, whilst at the same time limiting the dispersal of seeds of native fynbos species.
|Number of pages||2|
|Publication status||Published - 2017|