Using inert dusts to detect and assess varroa infestations in honey bee colonies

Abstract

SUMMARYDetection and assessment of varroa infestations in honey bee colonies are important for successful beekeeping. We examined the use of inert dusts to dislodge mites from adult honey bees that were isolated from their nest. Six dusts (powdered sugar, fine sugar, wheat flour, talcum powder, corn starch and baking soda) were evaluated for their ability to dislodge mites from adult bees collected in jars. We obtained the highest recovery rate with powdered sugar (92.9 ± 5.5%) and talcum powder (84.0 ± 5.6%). We also examined mite survival after recovery with inert dusts and compared it to mite survival after recovery from brood. After 24 h mite survival was significantly greater when mites were recovered with corn starch, powdered sugar, and from brood (F = 22.88, d.f. = 6,35, P <0.0001). Finally, ether and powdered sugar were compared as tools for detecting and assessing the degree of infestation. Powdered sugar did not differ from ether in detecting or assessing low (1-5 mites per sample) infestation levels (F = 2.81, d.f. = 1,49, P = 0.1). At medium (6-30 mites per sample) and high (> 30 mites per sample) infestation levels, more mites were recovered with powdered sugar (medium: F = 14.28, d.f. = 1,29, P = 0.008; high: F = 6.34, d.f. = 1,17, P = 0.023).

Varroa-specific hygienic behavior of Apis mellifera scutellata in Kenya

“…Colonies were housed in standard Langstroth hives containing eight-ten brood combs and were placed on stands protected by oil-filled cans to prevent ants from climbing and entering the hives and causing absconding of bees (Kinati et al 2012). Sugar roll assay was done to obtain mites that were used for artificial infestation (Macedo et al 2002;Dietemann et al 2013). …”

A strategy for using powdered sugar to reduce varroa populations in honey bee colonies

“…We increased percentage mite fall to 76.7 ± 3.6% in our secondary study by adding solid bottoms to our bee boxes. We did not succeed in removing 90% of the mites from adult bees isolated from their nest material as reported by Macedo et al (2002). One reason we did not achieve 90% mite fall may be attributed to not using screened bottom boards to monitor mite fall after returning bees to their colonies following treatment.…”

“…Macedo et al achieved 92.9 ± 5.5% mite fall when dusting 318 ± 7 adult bees in a screened jar with powdered sugar and reported no injury to bees or mites. Our objective was to test the hypothesis that powdered sugar could be used to remove approximately 90% of mites from adult bee populations when isolated from their nest material based on the findings of Macedo et al (2002). We predicted that isolation of a colony's adult bee population would ensure even distribution of powdered sugar and eliminate the possibility of mites reattaching themselves to adult bees after dislodgement.…”

“…Fakhimzadeh's results indicate that dusting colonies with powdered sugar significantly accelerated mite fall. Macedo et al (2002) reported using powdered sugar to detect and assess varroa infestations in honey bee colonies. Their method requires collection of approximately 300 adult honey bees in a screened jar.…”

Comparative evaluation of sticky paper and hive debris as sampling methods for population assessment of <italic>Varroa destructor</italic> in <italic>Apis mellifera</italic> colonies

“…Delaplane and Hood (1997) reported that sticky bottom boards are more reliable sampling method for making treatment decisions. Macedo et al (2002) used inert dusts including powdered sugar to detect and access Varroa population in A. mellifera colonies in USA. Thus, Sticky boards are better sampling method as compared o hive debris.…”