Pesticides And Honey Bees

Over the past few decades there has been heightened concern about the plight of honey bees as well as other bee species. Given the importance of honey bees and other bee species to food production, many have expressed concern about whether a “pollinator crisis” has been occurring in recent decades. Although honey bee colony losses due to bee pests, parasites, pathogens, and disease are not uncommon, there is the perception that bee health has been declining more rapidly than in prior years, both in the United States and globally. This situation gained increased attention in 2006 as some commercial beekeepers began reporting sharp declines in their honey bee colonies. Because of the severity and unusual circumstances of these colony declines, scientists named this phenomenon colony collapse disorder (CCD). Since then, honey bee colonies have continued to dwindle each year, for reasons not solely attributable to CCD. The U.S. Department of Agriculture (USDA) reports that CCD may not be the only or even the major cause of bee colony losses in recent years. In the United States, USDA estimates of overwinter colony losses from all causes have averaged nearly 30% annually since 2006. The precise reasons for honey bee losses are not yet known. USDA and most scientists working on the subject seem to agree that no research conclusively points to one single cause for the large number of honey bee deaths. This general conclusion was reconfirmed in a 2013 joint report by USDA and the U.S. Environmental Protection Agency (EPA). Reasons cited for bee declines include a wide range of possible factors thought to be negatively affecting pollinator species. However, one issue widely noted is the role that pesticides—in particular, neonicotinoid pesticides—might play in overall bee health. Pesticides are the focus of this report. Pesticides are among many identified factors known to affect bee health, including pests and diseases, diet and nutrition, genetics, habitat loss and other environmental stressors, and beekeeping management issues, as well as the possibility that bees are being negatively affected by cumulative, multiple exposures and/or the interactive effects of several of these factors. The focus of this report on bee exposure to pesticides is not intended to imply that pesticides are any more important in influencing the health and wellness of bees than other identified factors influencing bee health. Pesticides are one of many influences on bee health. The current state of knowledge on pesticides and bee health is summarized in the USDA-EPA report: it is not clear, based on current research, whether pesticide exposure is a major factor associated with U.S. honey bee health declines in general, or specifically affects production of honey or delivery of pollination services. It is clear, however, that in some instances honey bee colonies can be severely harmed by exposure to high doses of insecticides when these compounds are used on crops, or via drift onto flowers in areas adjacent to crops that are attractive to bees.

Bees, both commercially managed honey bees and wild bees, play an important role in global food production. In the United States, the value of honey bees only as commercial pollinators in U.S. food production is estimated at about $15 billion to $20 billion annually. The estimated value of other types of insect pollinators, including wild bees, to U.S. food production is not available. Given their importance to food production, many have expressed concern about whether a “pollinator crisis” has been occurring in recent decades. In the United States, commercial migratory beekeepers along the East Coast of the United States began reporting sharp declines in 2006 in their honey bee colonies. The U.S. Department of Agriculture (USDA) reports that overwinter colony losses from 2006 to 2011 averaged more than 32% annually. This issue remained legislatively active in the 110th Congress and resulted in increased funding for pollinator research, among other types of farm program support, as part of the 2008 farm bill (P.L. 110-246). Congressional interest in the health of honey bees and other pollinators has continued in the 112th Congress (e.g., H.R. 2381, H.R. 6083, and S. 3240) and may extend into the 113th Congress. This report: Describes changes in managed and wild bee populations, given readily available data and information. It focuses on managed and wild bees only, and excludes other types of pollinators, including other insects, birds, and bats. Data on managed honey bees are limited, and do not provide a comprehensive view of changes in bee populations. Data for wild bee populations are even more limited; Provides a listing of the range of possible factors thought to be negatively affecting managed and wild bee populations. In addition to pesticides, other identified factors include bee pests and diseases, diet and nutrition, genetics, habitat loss and other environmental stressors, and beekeeping management issues, as well as the possibility that bees are being negatively affected by cumulative, multiple exposures and/or the interactive effects of each of these factors; Briefly summarizes readily available scientific research and analysis regarding the potential role of pesticides among the factors affecting the health and wellbeing of bees, as well as the statutory authority and related regulatory activities of the U.S. Environmental Protection Agency (EPA) related to pesticide use. A 2007 report by the National Research Council of the National Academy of Sciences, Status of Pollinators in North America, provides a more detailed scientific context for this report and may be consulted for more in depth understanding about bee health. That study concluded that many factors contribute to pollinator declines in North America, and CRS accedes to that conclusion. Accordingly, the focus of this report on bee exposure to pesticides is not intended to imply that pesticides are any more important in influencing the health and wellness of bees than any of the other identified factors influencing bee health. Pesticides are only one of the many influences on bee health. Because neonicotinoid pesticides have been the focus of concerns in Europe and in the United States, this report briefly describes recent scientific research related to possible effects of exposure to these pesticides on bees. The report concludes with a summary of recent regulatory activity regarding neonicotinoids at EPA, the federal agency charged with assessing risks and regulating U.S. sale and use of pesticides.

Pollinators-insects, birds, bats, and other animals that carry pollen from the male to the female parts of flowers for plant reproduction-are an essential part of natural and agricultural ecosystems throughout North America. For example, most fruit, vegetable, and seed crops and some crops that provide fiber, drugs, and fuel depend on animals for pollination. This report provides evidence for the decline of some pollinator species in North America, including America's most important managed pollinator, the honey bee, as well as some butterflies, bats, and hummingbirds. For most managed and wild pollinator species, however, population trends have not been assessed because populations have not been monitored over time. In addition, for wild species with demonstrated declines, it is often difficult to determine the causes or consequences of their decline. This report outlines priorities for research and monitoring that are needed to improve information on the status of pollinators and establishes a framework for conservation and restoration of pollinator species and communities.