Invasive plant species have a negative impact on local fauna, such as pollinating insects, by transforming vegetation and decreasing floral resources. In three recent studies, researchers from the Centre for Ecological Research and Babeş-Bolyai University have investigated the effects of twelve herbaceous invasive plant species with different characteristics on vegetation (Fenesi et al. 2023), pollinator communities (Kovács-Hostyánszki et al. 2022) and functional traits of pollinating insects (Szigeti et al. 2023). Their results suggest that plant invasions do not have universal effects, with a few exception e.g. reduction of native vegetation diversity. There are differences among the studied invasive plants for almost all investigated ecological indicators. From a pollinator point of view, invaded sites act similarly to oilseed rape or sunflower fields: during flowering they provide a large amount of food for pollinating insects compatible with the flowers of the invasive plants present there, while over the blooming period they are green deserts. Effective conservation actions against invasive plant species are also important for the protection of pollinators. In contrast, some invasive species can provide important food resources for even protected pollinating insects. Thus, instead of only eradication, important to consider the local and species specific situation, and also consider the needs of the associated pollinator species.
Fenesi, A., Botta-Dukát, Z., Miholcsa, Zs., Szigeti, V., Molnár, Cs., Sándor, D., Szabó, A., Kuhn, T., Kovács-Hostyánszki, A. (2023). No consistencies in abundance-impact relationships across herbaceous invasive species and ecological impact metrics. Journal of Ecology;
Kovács-Hostyánszki, A., Szigeti, V., Miholcsa, Zs., Sándor, D., Soltész, Z., Török, E., Fenesi, A. (2022). Threats and benefits of invasive alien plant species on pollinators. Basic and Applied Ecology, 64:89–102;
Szigeti, V., Fenesi, A., Botta-Dukát, Z., Kuhlmann, M., Potts, S.G., Roberts, S., Soltész, Z., Török, E., Kovács-Hostyánszki, A. (2023) Trait-based effects of plant invasion on floral resources, hoverflies and bees; Insect Conservation and Diversity;