Work

Silent takeover: How invasive bees reshaped plant-pollinator interactions in a biodiversity hotspot

Year: 2026

Type: article

Abstract: Biological invasions are a major driver of biodiversity loss. Invasive pollinators can reshape native plant-pollinator networks. This study, taking Chile as an example, is divided into two parts. First, we assessed the impacts of three non-native pollinator species ( Apis mellifera , Bombus terrestris and Bombus ruderatus ) using over 2,100 records from scientific literature (including historical data) and citizen-science databases. Interactions were classified by plant origin (native or non-native) and analysed to characterise species roles. We found that B. terrestris dominated the interactions (73%), primarily with non-native plants and all three species exhibited generalist interaction patterns. Then, we evaluated the impact of B. terrestris on bee-plant interactions by building bipartite networks representing periods before and after 2005, when B. terrestris began to be used in open fields. We analysed network metrics including nestedness, specialisation, modularity and core-periphery structure, revealing that B. terrestris increased interaction frequency, displaced native species such as Bombus dahlbomii and contributed to a more nested, but less specialised network. Overall, our findings reveal that invasive bees silently, but profoundly reshape pollination networks – displacing native pollinators, reducing interaction specialisation and shifting systems towards homogenised structures that threaten native plant-pollinator mutualisms.

Source: NeoBiota

DOI: 10.3897/neobiota.105.174573