With a sting in their tails – examining hornets
I HAVE recently been ‘buzzed’ by wasps when sitting in my garden, in the early autumn sunshine at home in Somerset, UK. My house is a converted Victorian primary school with odd quirks in its redesign and a flying freehold of an airing cupboard alongside the bathroom. It was upon opening the door to this cupboard that I was met with a small swarm of wasps.
It seems likely that these ‘critters’ are nesting somewhere inside the very thick walls, gaining entry from an outside wall. My local pest controller is currently overworked on destroying wasp nests, so I patiently await my turn for his visit. Much to my relief, they are wasps and not hornets!
It was on a summer’s visit to Slovenia with my family in the early 1990s that we stayed on the shores of Lake Bohinj. One day we trekked up into the very high mountains to picnic alongside and later to have a refreshing swim in a glacial tarn (lake). It was getting near late afternoon and, with a long trek back down the mountain before darkness set in, we decided to take a narrow zigzag path back to our village.
After about a 30-minute scramble, we spotted a European hornet (Vespa crabro) nest slap bang in the middle of the very narrow path. There was no other way forward but to don our wet towels over our heads and faces and soldier on. Accidentally, our young son stumbled when trying to navigate this nest and split it apart. The air became alive with these dangerous insects, so we ran for our lives along the path and only lost them on the fourth bend downwards. We were lucky to escape without a single sting.
Several years later and for the first time, I encountered an Asian hornet (Vespa velutina) nest, which was pointed out to me by an observant Malaysian guide high up in the canopy of a belian tree in the rainforest. Later, on that same visit to Malaysia, I visited a friend’s open house to see him climb up a tall ladder to try to dislodge a hornet nest from a tree growing near to his front entrance. Once he had dislodged the nest, he slid like grease lightning down the sides of the ladder and ran! The nest hit the ground with a resounding thump and fortunately the ‘queens’ flew away followed swiftly by their entourage. Fortunately, not a single guest was stung.
Asian hornet (Vespa velutina)
This insect was given its Linnaean name by the French entomologist, Amedee Louis Michelle le Peletier in 1836 and is native to Southeast Asia but today this yellow legged hornet has become an invasive species in Europe. It is a highly aggressive predator of insects and, unlike European hornets when disturbed, gives a vicious sting to humans.
The ‘queen’ hornet grows up to 30mm in length and the ‘worker’ up to 25mm. Its thorax is velvety brown/black in colour with a brown abdomen. Each segment of its abdomen down to its tail shows a narrow horizontal yellow band apart from the lowest fourth segment, which is orange. It is quite distinctive with its black head and orange face but beware, for across the whole of Southeast Asia there are 13 or more varieties of hornet, each having a slightly different colouring.
Nesting
Their nests may house several thousand hornets in a colony. The nest construction is built of paper derived from their scouring of cellulose from the leaves and stems of local plants and is a huge egg shape, over a metre long. The entrance to the nest is made from the side rather than the bottom as in European hornet nests. Often a colony builds a nest in low lying shrubs which can be invaded by parasites. This nest is then abandoned after a few months and then the colony builds a new nest in the canopy of a tall tree. The young queens leave the nest later in the year to hibernate. It is the queens in the nest that hold destructive stings ready for defending the nest and killing their prey.
The entrance to the European hornet nest is at bottom. — Photo from needpix.com
Diet
They feed mostly on insects of all sorts, wasps, flies, dragonflies, and cockroaches, pursuing them in flight. With a particular penchant for honeybees, they hover above a bee’s nest or beehive and nest nearby to them. The Eastern honeybee is their preferred food.
The hornets ‘hawk’ bees by hovering around their nest, each occupying, above a beehive, an area of about 0.5 square metres and once catching a bee it bites off its head before taking the remains back to its nest. Unfortunately for bees, the hornets follow a similar circadian pattern with both species of insect emerging from their nests in the morning and afternoon and resting in their nests at dusk and evening.
Invasive species
Vespa velutina spread away from Southeast Asia, where these hornets were first spotted in a region near the port of Bordeaux in western France in 2004. These hornets are thought to have arrived from China in wooden boxes containing pottery. However, there is a high possibility that they may have been introduced from soil associated with imported plants, cut flowers, fruit, garden furniture and plant pots, freight containers and in/on imported timber.
By 2009 some 3,000 nests were destroyed in southwest France and six years later these hornets were seen throughout France slowly spreading to Italy, Spain, Portugal, and Germany, finally flying across to the UK in 2016.
Numerous apiarists’ honey businesses have been destroyed by these hornets and they are difficult to eradicate for mated queens over winter underneath the bark of trees, in cavities made by beetle larvae, under the soil, and in any small well insulated refuge before emerging in April and peaking in activity in August and September when ripe fruit adorns the fruit trees. Similarly Southeast Asian hornets have been spotted in South Korea and Japan, and even in Savannah, Georgia, USA.
Living literally on the county boundary of Somerset and Devon, these hornets have had nests spotted in Devon in 2023 and I fear they may be hovering closer to me than I would wish!
Threats to humans
If their nests are threatened by humans, they charge in a hoard towards a person with serious consequences causing death from multiple stings or anaphylactic shock. Most nests in the UK have been destroyed by pest controllers to protect people and private and commercial bee hives but there is always the fear that other unobserved nests may survive in barns, lockup garages, and even in people’s lofts.
Advice to readers
If you spot a hornet nest in your garden or when trekking in the forest or a park be careful to circumnavigate it and if living in a kampung or urban area report it to your local council for immediate action by the authorities. Never attempt to disturb it or destroy it yourself! If stung by a hornet, then do seek immediate medical advice and treatment for you never know how your body’s metabolism may react, as you could suffer anaphylactic shock. Don’t panic and stay as still as you can until medics arrive or you reach the nearest hospital.
Most of all remember that these devilish stingers are relatively harmless to us unless aggravated or disturbed. A single bee and wasp sting is relatively easy to treat with a dab of bicarbonate on the former and a dab of vinegar on the latter, having first removed the sting with tweezers. Multiple stings from either species are a hospital matter. Dealing with hornet stings is sadly beyond my first aid knowledge.
