Potential impact of Nootka lupine (Lupinus nootkatensis) invasion on pollinator communities in Iceland

INTRODUCTION Pollinator communities have an integral role in facilitating sexual reproduction within and between flowering plant populations. Declines in abundance and diversity of pollinating insects are widely documented throughout Europe, primarily the result of habitat loss and fragmentation (Fox 2013, Nieto et al. 2014, Goulson et al. 2015). In 1945, seeds of Nootka lupine (Lupinus nootkatensis Donn) were collected in Alaska, brought to Iceland, and introduced at reforestation sites. This plant’s invasiveness in Iceland was indicated by its tendency to replace native vegetation with homogeneous L. nootkatensis stands (Magnússon 2010). The lack of published research on Iceland’s broader pollinator community, combined with the dramatic changes in vegetation that have taken place over the last few decades, particularly with L. nootkatensis’s distribution, warrants an analysis of plant-pollinator relationships in Iceland, especially regarding L. nootkatensis. The present study aims to describe how pollinator communities differ between L. nootkatensis and the native flowering plants in heath habitat in south-west Iceland. The findings of this study will give an indication of whether L. nootkatensis can serve as an alternative food source for Iceland’s pollinator community, in the event that L. nootkatensis continues to replace native flowering plant communities throughout Iceland.