Asian hornets, Vespa velutina, are making lurid tabloid headlines after being regularly spotted in Kent over the last few years, says Richard Jones.
This originally Far East species was accidentally shipped to France in a cargo of ceramics in 2004 and has become widely established on the European mainland. Its sting is no worse than that of the docile European hornet, Vespa crabro, but its propensity to attack honeybees has alarmed beekeepers and raised it to pariah status.
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Could any deadly insects or bugs arrive in UK?
There have long been worries that other major nuisance pests might get to Britain if alterations in weather patterns and climate change continue. The reasoning was that many of these pests seem to prefer warmer climates and the British Isles’ reputation as a cold wet archipelago was no longer holding true.
The truth is complicated. Climate is an all-year-round thing, and just because there has been a hot spring does not necessarily mean there will be a wholesale invasion. To become established fully, any colonising species will need to be able to mate, breed and overwinter here. Simply hopping the English Channel to Kent or Sussex is no guarantee of triumphant conquest if the dull rains of autumn give you fungal disease (an important killer of overwintering insects) or the next spring arrives much later than your Mediterranean body clock got you up for, and you can’t find anything to eat.
Nevertheless, we should not be complacent. Just as Vespa velutina was anticipated, and checked (possibly!) by eradication attempts, so too other problem species can be anticipated and if they are spotted in time then they can be dealt with.
The Asian giant hornet, Vespa mandarina, another native of East and south-east Asia somehow got to the Pacific northwest of North America in 2019 and started another tabloid media storm. It’s huge, the largest social wasp in the world up to 50 mm long with a menacing orange head on its dull brown body. The press calling it ‘murder hornet’ simply stoked the panic.
This one is highly unlikely to manage trans-continental travel to Europe, but if a stowaway came in with freight it might find our climate conducive. Again it is not necessarily more aggressive or dangerous than other wasps or hornets, but it also attacks honeybees — beekeepers will not be impressed if it gets here.
The paper wasp, Polistes dominulus, may be familiar to anyone holidaying in Europe. They’re about the same size as other social wasps, but slimmer, and prettily marked. Rather poorly named (all social wasps make paper nests), it might be better called the umbrella wasp, because it makes a small umbrella-shaped nest, of about 100 cells, in a single arched comb hanging by a short stalk.
The comb is not covered by an outer paper carton (as are our currently native wasp species), and it can make them in rather exposed places — under a windowsill, on a branch just inside a small shrub. They tend to get knocked by passing legs or exposed by a bit of light pruning, and that’s when they attack to defend the nest. Odd vagrant specimens have been spotted in Britain for many years, and they were found nesting over several years in the early 2000s in the London area. This is definitely one that could become more common.
Could mosquitoes bring diseases to the UK?
It may come as a surprise to many that malaria used to occur in Britain — this was the ague of the Essex and Kent marshes. It was never very rife and drainage of the mosquito larvae’s ditch haunts and the discovery of quinine treatment meant the last recorded case was during the 1890s.
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However it came back when infected soldiers returning from both World Wars were convalesced in Kent, and the local mosquitoes picked it up from them to transfer to the local populace. Again, ditch clearance and DDT got things back under control.
But it does show that native British mosquitoes are quite capable of transmitting the disease if they can find a malaria carrier in the first place.
Another problem on the horizon may be dengue, because one of its best-known (worst-known?) carriers, the Asian tiger mosquito Aedes albopinctus is at our doors. This brightly spotted black and white mosquito is now common in southern Europe, and has been shipped all round the world as larvae breeding in the water slops in recycled tyres, for which there is a booming international trade. It is a decidedly urban species, with a propensity to come indoors and is known for being an aggressive biter. If it gets established here that does not mean the disease will definitely come, but it does make the disease one step closer.
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Could any deadly spiders come to the UK?
There are a few native spiders with jaws long enough, tough enough, and sharp enough to get through human hide and deliver a venomous nip — a bit like a wasp sting.
Media hype over false widows, Steatoda species, belies the fact that the death toll is still hovering around the zero mark. There is a true ‘black widow’ Latrodectus tredecimguttatus, native to southern Europe, and I dread to think what the press would make of it if that were to get accidentally introduced here. Yes, it can give a painful nip if picked up injudiciously between finger and thumb, but then so would I if you picked me up like that.
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The most important take is that new things arrive in Britain every year. Some survive the season, they may even breed here, but then they succumb to winter and disappear again. Others get established but are soon subsumed into the general ecology of a place and become part of the natural food-webs, with no serious knock-on effects.
Only a very few go on to reach pest proportions. And only a very, very, few have any serious detrimental effects on humans.
