Rapid climate change in the Arctic may increase sexual reproduction in plants because of changes inboth abiotic factors, such as temperature, and biotic factors, such as pollination. Pollination maycurrently limit plant reproduction in the Arctic, where cold temperatures hinder pollinator activity. Tounderstand how warming may affect pollination and plant reproduction, we studied three plantspecies in western Greenland. Two species were hermaphroditic and insect-pollinated (VacciniumuliginosumandChamerion latifolium), and one was dioecious and insect- and wind-pollinated (Salixglauca). We measured how pollinator visitation and plant reproduction varied across three tempera-ture zones. We also conducted pollinator exclusion and pollen supplementation experiments tomeasure pollinator dependence and pollen limitation. Proportion of fruit set inVacciniumandSalixwas pollen limited in every temperature zone, andVacciniumandChameriondepended on pollinator-mediated outcrossing for maximum reproductive success. Furthermore, higher pollinator visitation toVacciniumin the warmer temperature zones mirrored lower pollen limitation and higher fruit set,suggesting that temperature zone indirectly influenced reproduction via changes in pollination.Taken together, our results demonstrate that both abiotic factors and pollination are important inlimiting reproduction in the Arctic and that plant–pollinator interactions can mediate the response ofplant reproduction to warming.
