Starting in 2006, commercial migratory beekeepers along the East Coast of the United States 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). Current reports indicate that beekeepers in most states have been affected. Overall, the number of managed honey bee colonies dropped an estimated 35.8% and 31.8% in the winters of 2007/2008 and 2006/2007, respectively. Preliminary loss estimates for the 2008/2009 winter are reported at 28.6%. To date, the precise reasons for colony losses are not yet known. This report provides an overview of the importance of honey bee pollination to U.S. agricultural production, especially specialty crops. It describes the extent and symptoms of CCD and how it differs from previous honey bee colony losses, describing some of the reasons why scientists believe honey bee colonies are being affected by CCD. Finally, the report discusses policy options and actions that Congress has taken to address this issue. Honey bees ( Apis mellifera ) are the most economically valuable pollinators of agricultural crops worldwide and are the only bee species kept commercially in the United States. In the United States, bee pollination of agricultural crops is said to account for about one-third of the U.S. diet, and to contribute to the production of a wide range of high-value fruits, vegetables, tree nuts, forage crops, some field crops, and other specialty crops. The monetary value of honey bees as commercial pollinators in the United States is estimated at about $15 billion annually ( Table 1 ). Some studies report the estimated value of honey bee pollination at as much as $20 billion annually. This estimated value is measured according to the additional value of production attributable to honey bees, in terms of the value of the increased yield and quality achieved from honey bee pollination, including the indirect benefits of bee pollination required for seed production of some crops. About one-third of the estimated value of commercial honey bee pollination is in alfalfa production, mostly for alfalfa hay. Another nearly 10% of the value of honey bee pollination is for apples, followed by 6%-7% of the value each for almonds, citrus, cotton, and soybeans. Overall, pollinator-dependent crops are reported to make up an estimated 23% of total U.S. agricultural production in 2006, up from an estimated 14% in the 1960s. A number of agricultural crops are almost totally (90%-100%) dependent on honey bee pollination, including almonds, apples, avocados, blueberries, cranberries, cherries, kiwi fruit, macadamia nuts, asparagus, broccoli, carrots, cauliflower, celery, cucumbers, onions, legume seeds, pumpkins, squash, and sunflowers. Other specialty crops also rely on honey bee pollination, but to a lesser degree. These crops include apricot, citrus (oranges, lemons, limes, grapefruit, tangerines, etc. ), peaches, pears, nectarines, plums, grapes, brambleberries, strawberries, olives, melon (cantaloupe, watermelon, and honeydew), peanuts, cotton, soybeans, and sugarbeets. In the United States, most pollination services are provided by commercial migratory beekeepers who travel from state to state and provide pollination services to crop producers. These operations are able to supply a large number of bee colonies during the critical phase of a crop's bloom cycle, when honey bees pollinate a crop as they fly from flower to flower collecting nectar and pollen, which they carry back to the nest. Data from the U.S. Department of Agriculture's (USDA) 2007 Census indicate that there were about 28,000 operations with 2.9 million bee colonies in the United States. The majority of these, more than 2 million bee colonies, are reported to belong to commercial migratory beekeepers. The Dakotas accounted for a combined 27% of all bee colonies. Another one-fifth of all colonies are in California (about 14%) and Florida (7%). Montana, Minnesota, Idaho, and Texas accounted for 4%-5% each of all colonies nationwide. Other states with a large number of bee colonies were Michigan, Oregon, Georgia, Nebraska, New York, Washington, Wisconsin, and Wyoming, with about 2% each. Although these operations also produce honey for commercial sale, it is their value as crop pollinators that provides the greatest economic impact in the production of food and feed crops. It is estimated that, each year, more than 2 million bee colonies are rented for U.S. crop pollination. Available limited information indicates that the greatest number of honey bee colony rentals are for apple and almond production, followed by clover seed, cherries, and pears. About one-half of the nation's honey bee colonies (an estimated 1.3 million colonies) are used to pollinate California's current 550,000 acres of almond trees, and this need is projected to grow to 1.5 million colonies by 2010. Both locally and globally, there are concerns that growth in the availability of honey bee stocks is not keeping pace with growing agricultural demands for pollination services. Rental fees collected by commercial beekeepers for pollination services may vary by crop type, and often tend to be lower for some seed crops and higher for berry and tree crops. In recent years, pollination fees paid by crop producers have increased. For example, fees paid by California's almond industry have risen from a reported $35 per colony in the late 1990s to about $75 per colony in 2005. More recent estimates of fees for pollinating almond trees are even higher, at $150 per colony or more. Among the reasons for higher pollination fees are expanding almond acreage and relatively high honey prices, but also fewer available honey bees for pollination due, in part, to colony declines and bee mortalities. Starting in the last three months of 2006, a seemingly new phenomenon began to occur based on reports of an "alarming" number of bee colony losses and die-off along the East Coast. By the end of 2006, beekeepers on the West Coast also began to report "unprecedented" losses. Available estimates indicate that beekeepers in 35 states have been affected ( Figure 1 ). Because of the severity and lack of precedent, scientists coined a new term, Colony Collapse Disorder (CCD), for this phenomenon. Much of the current research on CCD is being conducted by scientists at USDA's Agriculture Research Service (Beltsville bee laboratory), Pennsylvania State University, the University of Montana, and the Pennsylvania and Florida Departments of Agriculture, among others. Many of these researchers also participate in the CCD Working Group, which includes Bee Alert Inc., the Florida and Pennsylvania Departments of Agriculture, Pennsylvania State University, and USDA. Up-to-date information is regularly posted to the website of the Mid-Atlantic Apiculture Research and Extension Consortium (MAAREC), which represents beekeeping associations in New Jersey, Maryland, Delaware, Pennsylvania, and West Virginia. Honey bee colony losses are not uncommon. A recent report by the National Research Council (NRC) documents the extensive literature on honey bee population losses due to bee pests, parasites, pathogens, and disease. Most notable are declines due to two parasitic mites, the so-called vampire mite ( Varroa destructor ) and the tracheal mite ( Acarapis woodi ), and also colony declines due to the pathogen Paenibacillus larvae . Other reasons for bee colony declines reported by the NRC include interspecific competition between native and introduced bees, pathogen spillover effects, habitat loss, invasive plant species that reduce nectar- and pollen-producing vegetation, bee genetics, and pesticides, among other factors. Mite infestations are a relatively new occurrence. The 1980s saw two periods of large die-offs due to Varroa and tracheal mites: The first Varroa mite infestation was reported in 1987; tracheal mites were first detected in 1984. Varroa mites are also said to have eliminated most feral bee colonies in the mid-1990s. Varroa parasitism affects both worker bees and male larvae and can affect the ability of the queen to reproduce. It is associated with viral pathogens and if left untreated can cause colony mortalities usually within six months to two years after the initial infestation. Less is known about the effects of the tracheal mite. The pathogen Paenibacillus larvae is the most serious honey bee pathogen and causes American foulbrood (AFB), which is a disease of larval honey bees. AFB resulted in large colony losses in the 1940s, but its incidence has been reduced by the use of antibiotics and increased apiary inspection programs. Nevertheless, mite and pathogen infestations have likely raised beekeeper operating costs to pay for miticides and/or antibiotics, labor and expenses for treatment, improved management and inspection, and colony replacement of dead bees. Symptoms similar to those observed for CCD have been described in the past, and heavy losses have been documented. It is still not clear whether the current colony losses are being caused by the same factors or if new contributing factors are involved. MAAREC also reports that large beekeeper operations may have experienced higher than normal losses compared with the past few years, and heavy overwintering losses were reported in 2003-2004 for many northern beekeepers. Overall, USDA reports that bee colony losses have averaged 17%-20% per year since the 1990s, attributable to a variety of factors, such as mites, diseases, and management stress.