Small hive beetle: An emerging Washington State honey bee pest

The small hive beetle (SHB), Aethina tumida, is a honey bee pest that was first introduced to the United States in the 1990s, and has spread to every continent except Antarctica. Native to sub-Saharan Africa, SHB are known to detrimentally affect honey bee colonies, bumble bee and stingless bee colonies, and some solitary bee nests. The widespread invasion of these beetles is likely a result of global movement of honey bee colonies and products. SHB prefer climates with high humidity and temperatures for successful reproduction. Historically, the small hive beetle has been considered only a transient pest introduced from packages or bee products, with little potential to establish in Washington State. However, in the past three years, we have confirmed reports of sustained populations of this pest from beekeepers in northwestern WA. Climate change may be contributing to the expansion of suitable habitat for this invasive species. Using ecological niche models of SHB survival and developmental viability, we created a heat map that shows potential habitat suitability in Washington State. Using these data, we have created an educational extension document informing beekeepers about SHB as an emerging honey bee pest to look out for in Washington. The factsheet describes the potential habitat range in Washington State, impact on honey bee colonies and honey storage, management strategies, and an identification guide for SHB and another common honey bee pest, wax moth, to help beekeepers accurately assess and report the presence of SHB in their hives.