The role of imidacloprid systemic insecticide on colony collapse disorder of honey bees and decline of bumble bee pollinators

Project Overview

Project Type: Research and Education
Funds awarded in 2009: $175,000.00
Projected End Date: 12/31/2010
Region: North Central
State: Minnesota
Project Coordinator:

Annual Reports


  • Animal Products: honey


  • Pest Management: general pest management

    Proposal abstract:

    Pollinators in general are experiencing serious decline and honey bee colonies are experiencing conspicuously high mortality due to an event now called Colony Collapse Disorder (CCD). Systemic neonicotinyl insecticides, which replaced organophosphates, are considered as a factor in bee decline. Most of the research on the effects of neonicotinyl insecticides on honey bees focused on the translocation to nectar and pollen of Gaucho (imidacloprid) seed application. However, soil applications for crops and landscape plants use greater concentrations of imidacloprid applied closer to flowering. Gaucho seed application resulted in 1.9 ppb imidacloprid in sunflower nectar and 0.6 to 0.8 ppb in canola nectar. Soil applied imidacloprid was translocated to buckwheat nectar at 16 ppb and milkweed nectar at 41 ppb/flower (Marthon 1%G). These concentration of imidacloprid caused high mortality of beneficial insects, such as lady beetles, lacewings, and a small parasitic wasp. However, the effect on bees of these higher concentrations has not been studied. In the field on canola we will use a seed and soil application, perform residue analysis on nectar, pollen, and bees. We will work with beekeepers on their land, and monitor honey bee mortality and behavior. We will work with state agencies, commodity groups, and growers to disseminate this research-based information on how to protect and promote bees. We will suggest alternative insecticides that are more bees friendly to be used in crops and landscapes that now use imidacloprid. Also, to lure bees from treated areas, we will develop lists of pollinator friendly plants to be used in natural resources management, such as conservation plantings, roadsides, and restoration.

    Project objectives from proposal:

    The short term outcomes of this research are to change our knowledge base and behavior by determining if two different imidacloprid applications, Gaucho seed and soil applications, are translocated to nectar and pollen and kill bumble bees and honey bees. The research will provide information to beekeepers and growers (change our knowledge) concerning the effects of imidacloprid applications on the behavior and survivorship of bumble bee and honey bee pollinators. Imidacloprid is a neocicotinoid, a class of systemic insecticide modeled after nicotine, which is translocated through plants to nectar and pollen. This research is critical in determining if neonicotinoids may be a contributing factor in catastrophic bee deaths and general pollinator decline. Without bee pollinators, many crops cannot bear fruits and sustainable agriculture and organic production can be jeopardized.

    The intermediate outcomes are to change behavior and use this research-based information to work with state agencies and farmers to develop management plans that use alternative insecticides in landscape plants and crops visited by bees. Since pollinators move between crop fields and urban landscapes, the development of management practices to maintain these insects is extremely urgent. It is argued that at the current rates of pollinator loss, food crops may not have pollinators in 50 years. Also, we will develop lists of specific native nectar plants for natural resources management, such as conservation plantings, roadsides, and restoration projects.

    The long term outcome is to promote and maintain pollinators for crops and natural resources. If systemic insecticides are detrimental to this goal, then at a minimum our research can be used to change EPA labels to add cautionary information about risks to pollinators.

    The results of this research will increase the profitability of beekeeping and therefore of fruit and vegetable growers, and will improve environmental quality by promoting uncontaminated floral resources for honey bees and bumble bees, vital pollinators of our agro- and natural ecosystem.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.