Asian Hornets an uninvited species turned permanent resident

By Graham Mortimer

They have now settled in their tens of thousands.

You will have seen some reports about the invasive non-native insect which was accidentally introduced into France in 2004 in a consignment of goods from East Asia and rapidly spread across Europe. The first sighting in UK was in 2016 and sporadic colonies were found and destroyed mostly around ports Dover, Southampton, Portsmouth and bizarrely Woolacombe. The pregnant queens probably hitched a ride on ferries carrying fruit or simply stuck in the grill of a holidaymaker’s car grill. Some say that they can be blown across the Channel by the wind.

Whatever the cause the Asian Hornet (AH) is now an enormous threat and following the aggravation of a few nests in fairly predictable areas , albeit difficult to find, they are now becoming established. Last year dozens of nests were found in Kent alone. Up to now there have been no verified sightings in West Sussex but we are surrounded!

It is not now just accidentally imported queens/colonies but they are breeding, becoming established and moving inland from the coast. Nests have been found in Hastings and The New Forest. Global warming has not helped at all.

Beekeepers with managed hives have been amongst the first to witness the AH’s activities as they ‘hawk’ around the hive picking off the bees when they return with their loads of pollen and nectar. Those they don’t kill remain scared and hide in the hive, the honeybee queen stops laying, there is no gathering of food and they starve to death. A hive is very quickly decimated.

The AH is not only a threat to the more obvious targets of honeybees but also to all pollinators, bumble bees, mason bees and all solitary bees, wasps etc. The AH is carnivorous and go for meat and fish in open air markets (not so prevalent here), they are opportunists and feed on road kill and other rotting carcases. They also like ripe sweet fruit and vineyards in France have failed due to their activity, there are plenty of potential targets around us.

We are now at a ‘tipping point’ at the end of the phony war and we are fully expecting the population to increase dramatically. Right now over-wintered and pregnant AH queens are emerging from their individual hibernation hideaways having survived last year’s nest destruction, or freshly arrived from France. The queen firstly constructs an embryo nest about 4-5cm in diameter and looking much like a wasp nest and hanging in a dry place. It will contain eggs and larvae but no workers. This is the ideal time to report the sighting to the Asian Hornet Watch team to put a stop to the development of a colony and nip the process in the bud.

When the first worker AHs emerge they construct a larger nest, often high in a tree but also in other inaccessible spots such brambles or even cliff edges. Each nest may contain around 5/6000 AHs of which 180-500 will be queens ready to start the whole cycle again. By comparison a colony of 40,000-60,000 honeybees will only have one queen!

We need the general public to be aware of this dangerous non native invader turned permanent resident and report sightings to Asian Hornet Watch by downloading the free app on iphone or Android or reporting by email alertnonnative@ceh.ac.uk. Always try to take a photo and give a precise location. The team will try to capture the AH alive, mark, track and triangulate, with other sightings, determine its destination and hopefully destroy the nest. Don’t kill the AH it is vital that its nest is found.

The AH is slightly smaller than our native European Hornet with bright yellow tips to their legs. The AH abdomen has one segment (the 4th) in yellow/orange the European Hornet has several yellow hoops (much like a rugby shirt!). It has a venomous 6mm sting and could be a threat to agricultural workers, those clearing undergrowth or even schoolchildren if they disturb a nest.