The interactions between native bees and alien plants

Abstract

This thesis examines the interactions between native bees, in particular bumblebees (Bombus spp.), and the alien plants they visit. Most alien plants are well integrated into the resident plant-pollinator network. They are thus likely to directly and indirectly affect the foraging behaviour, resource use, and the abundance and diversity of individuals, populations and communities of native generalist pollinators as they may augment but also alter the availability and composition of forage resources, by attaining large floral densities and possibly displacing native plants. To date only a limited number of studies have studied the indirect and direct impacts of alien plants on native bees. I investigated the interactions between native bees and alien plants through observational and experimental field studies that took place in sites along the River Liffey and on Howth, Co. Dublin (Eastern Ireland) and in Spiddal, Co. Galway (Western Ireland).