The Impact of a Pesticide Ban on a Pollinator Community
Lead Research Organisation:
University of Bristol
Department Name: Biological Sciences
Abstract
THE IMPORTANT ENVIRONMENTAL CHALLENGE BEING ADDRESSED: Pollinators provide a crop pollination service worth £174 to £346 billion each year and 90% of flowering plants depend on animal-mediated pollinator services. While the impact of pesticides on this service is a cause of significant concern worldwide, most research on this topic has been limited in scope and environmental realism, with the majority of studies limited to a single pollinator species under laboratory conditions. Studies which used field trials to test pesticide impacts remain very rare, use very small numbers of pollinator species (e.g. n=3) and are limited to the scale of crop fields, which are generally the largest units of area that can feasibly be manipulated (e.g., Woodcock et al. 2017 doi: 10.1126/science.aaa1190 & Rundlof et al. 2015 doi:10.1038/nature14420). However, in Guernsey - an island undergoing a pesticide ban - we have a unique one-off opportunity to test the impact of pesticides on a whole pollinator community at the scale of an entire ecological system. Moreover, we have replicate islands nearby to use as controls and we have already collected a considerable quantity of baseline data on pollinator population density and community structure prior to the ban.
THE AIM OF OUR GRANT APPLICATION is to quantify the impact of a pesticide ban on a pollinator community and test for cascading impacts on the wider food web. The ban is being implemented on the island of Guernsey, and we will use three neighbouring islands (Jersey, Alderney and Sark) as controls. Using a small grant along with logistical support provided by a local NGO, we have collected a substantial 4-year baseline dataset. If our research proposal is funded, we will have a unique seven-year run of continuous data covering the period before, during and after the pesticide ban on Guernsey and our control islands.
THERE ARE FOUR OBJECTIVES TO OUR PROJECT. First, we will quantify the impact of the pesticide ban on populations of the buff tailed bumblebee, five species of hoverfly and two species of moth, predicting increases in all these indicator species following the ban. Second, we will quantify the impact of the ban on pollinator community structure, predicting a greater rebound in pollinator groups which are known to be particularly sensitive to pesticides. Third, we will test for cascading positive benefits of the ban on the wider community associated with pollinators, specifically their specialist parasitoids and generalist bat predators. Finally, we will use our results and management recommendations to inform and facilitate impact at a local, national, and international level.
METHODS: Our field sites are four islands in the Channel Island archipelago - Guernsey and three adjacent control islands - which are close to the French coastline and made up of two self-governing British Crown Dependencies. We will use a Before-After-Controlled-Impact design to sample pollinators, which combines multiple control and reference sites with multi-year sampling before and after the pesticide ban. This allows us to distinguish the impact of the ban from other variables which are well known to affect insect populations, most obviously the weather. Indeed, our baseline data shows we can detect an increase in pollinator abundance as small as 10%, which is a game changer in this field of research.
SUMMARY: Overall, the combination of our rigorous sampling protocols, our unique island system, and the fact that we have the pre-ban data "in the bag", will enable us to advance the frontiers of knowledge on the impact of pesticides on pollinators at an unmatched scale. Our innovative community level approach has not been attempted before and will lead to ground-breaking scientific discovery. Although it is complex and high-risk to detect changes in ecological communities at such scale, our baseline data demonstrates that our approach is eminently feasible.
THE AIM OF OUR GRANT APPLICATION is to quantify the impact of a pesticide ban on a pollinator community and test for cascading impacts on the wider food web. The ban is being implemented on the island of Guernsey, and we will use three neighbouring islands (Jersey, Alderney and Sark) as controls. Using a small grant along with logistical support provided by a local NGO, we have collected a substantial 4-year baseline dataset. If our research proposal is funded, we will have a unique seven-year run of continuous data covering the period before, during and after the pesticide ban on Guernsey and our control islands.
THERE ARE FOUR OBJECTIVES TO OUR PROJECT. First, we will quantify the impact of the pesticide ban on populations of the buff tailed bumblebee, five species of hoverfly and two species of moth, predicting increases in all these indicator species following the ban. Second, we will quantify the impact of the ban on pollinator community structure, predicting a greater rebound in pollinator groups which are known to be particularly sensitive to pesticides. Third, we will test for cascading positive benefits of the ban on the wider community associated with pollinators, specifically their specialist parasitoids and generalist bat predators. Finally, we will use our results and management recommendations to inform and facilitate impact at a local, national, and international level.
METHODS: Our field sites are four islands in the Channel Island archipelago - Guernsey and three adjacent control islands - which are close to the French coastline and made up of two self-governing British Crown Dependencies. We will use a Before-After-Controlled-Impact design to sample pollinators, which combines multiple control and reference sites with multi-year sampling before and after the pesticide ban. This allows us to distinguish the impact of the ban from other variables which are well known to affect insect populations, most obviously the weather. Indeed, our baseline data shows we can detect an increase in pollinator abundance as small as 10%, which is a game changer in this field of research.
SUMMARY: Overall, the combination of our rigorous sampling protocols, our unique island system, and the fact that we have the pre-ban data "in the bag", will enable us to advance the frontiers of knowledge on the impact of pesticides on pollinators at an unmatched scale. Our innovative community level approach has not been attempted before and will lead to ground-breaking scientific discovery. Although it is complex and high-risk to detect changes in ecological communities at such scale, our baseline data demonstrates that our approach is eminently feasible.
