The National Honey Bee Disease Survey: Varroa & Nosema in the US
The National Honey Bee Disease Survey investigates honey bee apiaries throughout the US to see if three exotic honey bee pests are still absent from our shores. Samples collected from 41 states and two territories reveal that we are still free of the Tropilaelapsmite, Slow bee paralysis virus, and the Asian honey bee Apis cerana. If you think varroa is tough to manage, its diminutive cousin Tropilaelaps can reproduce much faster, resulting in many more mites feeding on developing honey bee larvae. We dont want any of these three exotics as they would add additional stress and pressure to honey bee health.
While sampling for these exotics, we used the opportunity to collect additional data on the health of honey bees nationwide. We sampled for varroa, nosema and a suite of honey bee viruses. Here we report on the varroa and nosema results.
Varroa levels typically peak in late summer and early fall, when the average infestation rate nationwide rises above the treatment threshold. This means too many colonies are entering the winter with a high parasite load, making it more difficult for them to survive the winter.
Image courtesy of beeinformed.org