The specialised buzz pollination syndrome poses a partial barrier to plant invasions

Abstract

Abstract Plants that exhibit generalised pollination syndromes have been hypothesised to become invasive more easily compared with specialists, yet the degree to which specialised pollination traits inhibit plant invasions is unknown. One such specialisation is the buzz pollination syndrome, which encompasses specialised floral traits that restrict pollen access (typically poricidal anthers) and benefits from specialised insect behaviour for pollen extraction. We reviewed the literature on buzz pollination of invasive plants to assess whether: (1) plant species exhibiting specialised pollination syndromes are underrepresented as invasive species, and (2) species with specialised pollination syndromes that have become invasive can reproduce in the absence of specialist buzzing pollinators. Synthesis. We found 2.5% (117/4630) of invasive angiosperms have poricidal anthers, which is an underrepresentation of the proportion of global angiosperms that are estimated to have poricidal anthers (6%–10%). Most invasive buzz‐pollinated plants are genetically self‐compatible (97%), but only 43% can set fruit in the absence of a pollinator. Our findings highlight the importance of establishing new pollinator mutualisms for sexual reproduction. However, we identified six non‐buzzing behaviours used to extract pollen from plants with poricidal anthers, which is important where buzzing pollinators may be absent or not attracted to newly introduced plant species.