2012 Annual Report
1a.Objectives (from AD-416):
The Areawide Program will bring together recent improvements in mite-resistant bee stocks, nutrition, and pest and disease management techniques into a comprehensive management strategy to improve honey bee health in the U.S. The objective of this program is to increase colony survival and availability for pollination and thus increase the profitability of beekeeping in the U.S.
1b.Approach (from AD-416):
The program will focus on bringing together ARS research from Beltsville, MD; Tucson, AZ; Baton Rouge, LA and Weslaco, TX. Specific objecives include: HFCS research results (Weslaco);.
3)parasitic mite management techniques including new chemical controls 2-heptanone (Tucson), Hivastan (Weslaco) and non-chemical controls plastic drone comb (Beltsville) and screen bottom boards (Beltsville);.
4)Nosema controls (Weslaco and Beltsville). A year-round management scheme will be tested in large migratory and smaller non-migratory beekeeping operations with an emphasis on the larger migratory beekeepers that supply bees to almonds (almost half of all managed bees in the U.S.). The country will be divided into geographic regions as follows: East, Mid-West & West. It is imperative to test in many geographic regions as bees, bee pests and diseases grow at different rates in different parts of the country.
The Areawide Program responsibility for the Honey Bee Research Unit in Weslaco, Texas, is California and Texas. A series of large-scale field trials were conducted in California and Texas, testing the hypothesis that colonies compromised by poor nutrition are much more likely to succumb to the parasitic mite Varroa destructor and the microsporidian Nosema ceranae. We showed that colonies that moved to higher elevations survived winters, with larger adult bee populations. Optimum time for feeding protein to honey bee colonies in preparation for almond pollination was from September through February. Two experiments showed that winter feeding should be started early for maximum effect. Honey bee survival and performance, when fed six experimental pollen substitutes, indicated that performance on two of the experimental diets was as good as the standard diet, Mega Bee. Experiment on controlling Nosema ceranae with eight experimental medications found that none of the products were efficacious. We conducted three large field experiments with novel treatments; nothing to date has been as efficacious as the industry standard, fumagillin. Almond pollen collection by honey bee colonies heavily infested with Nosema ceranae were severely impacted.
A field study with 400 colonies was conducted in southern Louisiana. Treatment groups included all combinations of three stressors: nutrition, varroa, and nosema. Colonies were moved to California for February-March almond pollination and then returned for honey production. Colonies starting this experiment with ca. 150 varroa dropping naturally onto a sticky board during a 72-hour period were generally unable to meet a 6-frame minimum strength criterion no matter what palliative treatment or feeding was received. Colonies with initial high mite loads showed significantly depressed honey production. Colonies not treated with fumagillin showed severe strength reduction; colony death was, in almost all cases, preceded by queenlessness. The length of time a queen survived was inversely correlated with the number of varroa, and to a lesser degree, the nosema level at the start of the experiment.