Moths can transfer pollen between flowers under experimental conditions

To be considered an effective pollinator, a floral visitor must not only be able to remove pollen but also transfer this pollen to a receptive conspecific stigma. While studies of diurnal pollination are commonplace, our understanding of the effectiveness of nocturnal pollinators is limited largely because of the difficulties of doing these studies at night. As a result of this, the way in which moths transfer pollen between flowers has been understudied globally, despite many authors suggesting they could be significant contributors to pollination. Here, we tested whether moths are capable of transferring pollen between flowers under experimental conditions using a fluorescent pollen-tracker powder. A flower-feeding taxon (Noctuidae: Ichneutica plena) and non-feeding taxon (Hepialidae: Wiseana spp.) were contained overnight with flowering shoots of putatively moth-pollinated Leptospermum scoparium and Pimelea prostrata (I. plena only), and putatively bird-pollinated Crocosmia × crocosmiiflora. Moths were able to transfer pollen tracker between flowers for both of the putatively mothpollinated species, while no pollen tracker was removed from putatively bird-pollinated flowers. Both the feeding and non-feeding moth taxa were able to transfer pollen tracker between flowers; however, the feeding taxon could be considered a more effective pollinator because of the greater proportion of individuals both carrying and transferring pollen tracker compared with the non-feeding taxon. This study provides experimental evidence that moths may contribute to the pollination of L. scoparium and P. prostrata, and suggests a reassessment of the pollination ecology for these species is warranted.