A ground-breaking study, published on November 29, 2023, highlights that despite tightened pesticide regulations, bumblebees—key wild pollinators in Ireland—remain under threat. Conducted across 106 sites in eight European countries, the research reveals that current pesticide use in agriculture continues to harm bee populations, signalling that more needs to be done to protect them.

This large-scale study, published in Nature, demonstrates that even with Europe’s stringent risk assessment processes, approved pesticides still negatively impact non-target organisms like bumblebees. Specifically, the colony performance of these pollinators is significantly reduced when exposed to pesticide mixtures. Affected colonies showed reductions in cocoon production, colony weight, and queen numbers, all of which are crucial for bumblebee survival and their role in pollination.

Dr. Charlie Nicholson, co-lead author and researcher at Lund University, explained, “When bumblebees are exposed to multiple pesticides in agricultural landscapes, their reproductive success plummets. The issue is compounded in landscapes with fewer natural habitats, where pesticides have even more harmful effects.”

Dr. Jessica Knapp from Trinity College Dublin, another co-lead author, highlighted that colonies exposed to fewer pesticides performed much better. However, the study showed that 60% of bumblebee colonies failed to meet proposed pollinator protection standards, underscoring the inadequacy of current pesticide regulations.

The research is part of PoshBee, a major EU-funded project aimed at improving bee health. Prof. Mark Brown from Royal Holloway University of London emphasized the international scale of the project, noting the need for collaborative efforts to protect pollinators across borders.

Prof. Jane Stout from Trinity College Dublin praised the cross-disciplinary approach of the study, involving researchers, beekeepers, and farmers from 13 countries. She stressed that similar collaborations will be vital to turning the tide and providing the protection pollinators urgently need.

The findings also align with broader sustainability goals, such as the EU’s Farm to Fork strategy, which emphasizes the need to reduce pesticide use. Senior author Dr. Maj Rundlöf from Lund University concluded that this study supports the need for landscape-based environmental assessments to monitor the real-world effects of pesticide exposure on pollinators.

Ireland is already leading the way in reducing pesticide risks by 2050, but the study reinforces the importance of habitat restoration. The All Ireland Pollinator Plan plays a crucial role in boosting natural habitats, potentially mitigating some of the damage caused by pesticides.

For full details, the study is available on the Nature website.