introduction to France in 2003–2004. In just seven years V velutina has spread across at least 39 French départements (Figure 6) and was confirmed in North East Spain for the first time in November 2010. This has sparked understandable concern and some high profile media coverage (Figure 7). Although (unlike the exotic pests the small hive beetle and Tropilaelaps mites) the Asian hornet is not a statutory notifiable pest of honey bees, beekeepers in the UK need to be aware that there is the potential for this species to arrive and establish itself here.
Understanding the Risks of Arrival in the UK
The Non-native Species Secretariat (NNSS) has responsibility for helping to coordinate the approach to invasive non-native species in Great Britain (GB). The NNSS is responsible to a Programme Board representing the relevant governments and agencies of England, Scotland and Wales. You can read more about the activities of the NNSS at https://secure.fera.defra.gov.uk/nonnativespecies/ home/index.cfm. At the request of the NNSS, the NBU has undertaken a formal and extensive Non-native Organism Risk Assessment (NNORA) for V velutina with respect to beekeeping in the UK. The completed NNORA has recently been made public and can be viewed in full at: https://secure.fera.defra.gov.uk/nonnativespecies/index.cfm ?sectionid=51. Essentially, based on detailed consideration of available literature, scientific evidence and personal accounts, we sought to answer four key questions: ¿ How likely is it that the Asian hornet will arrive in the UK? ¿ How likely is it that it will establish in the UK? ¿ How likely is it to spread in the UK? ¿ What would be its impact?
Question 1. How likely is it that the Asian hornet will arrive in the UK?
The life-stage of the Asian hornet that poses the greatest risk of entry is a newly mated queen, because just one such inseminated female will found an entire colony comprised of several thousand offspring. It is believed that the entire population of Asian hornets in France originated from a single incursion. There are multiple (seven) pathways by which Asian hornet queens could, at least in theory, enter the UK. These are summarised in Table 1. It is our view that not all pathways pose an equal risk of entry; some include inspection procedures that will detect any insects (including hornets) before arrival, others have treatment measures in place that will kill hitch-hiking pests in transit. These pathways are considered in more detail below.