Dear Readers, with a name like ‘Bugwoman’ it isn’t surprising that people often ask me what the hell something that they’ve seen buzzing around their living room light or hanging about in the shed is. Sometimes, as with this extraordinary insect, they not only ask me but find a way to gently encourage it back to ‘the wild’ with the minimum of fuss. And so it was with a colleague and a giant wood wasp earlier this week – she sent me a picture so that I could identify it. Her calmness is all the more impressive because this is a large and scary-looking beast, which can grow to a massive (for the UK) 4 cms long. Don’t laugh, African and Australian folks! Our wildlife here is, shall we say, bijou, but that doesn’t stop some folk having hysterics about it. I dread to think what they’d do if the critters were actually dangerous. Here your highest chance of animal-related demise is being run over by an agitated cow.
Anyhow. I was very envious that my colleague spotted a giant wood wasp, because I would love to see one. The female has a large ovipositor at the back end so that she can inject her eggs into the soft wood of conifers, or cut pinewood – these creatures are most often seen in pine plantations, or occasionally hanging around timberyards wearing an innocent expression. Here is a female just about to start laying her eggs into a log. It’s during this period that the females are vulnerable to predation – you can sometimes find just the ovipositors sticking into the wood where a bird has flown off with the rest of the insect.
In order to attract a female, male giant wood wasps ‘lek’ – they gather in numbers at the tops of isolated or prominent fir trees, where they are likely to be seen by passing females. They also secrete a pheromone which will attract other wood wasps, so there can be impressive aggregations of the creatures. This also increases their exposure to predation, of course, but for the males the chance of passing on their genes seems to trump the danger of being eaten.
The larvae live for two to three years, getting nice and fat on the wood, before emerging. They get particularly fat because, along with the eggs, the female wasps inject a special fungus that will be ingested by the larvae, and will help them to digest the cellulose in the wood (a fascinating fact from ‘Wasps – the Astonishing Diversity of a Misunderstood Insect’ by Eric A. Eaton, a great read!)
Wood wasps have never been common creatures and so they aren’t a big problem for foresters in the UK, especially as they seem to prefer stressed rather than healthy wood, and so help to ‘tidy up’ dead trees. However, the larvae do sometimes decide to emerge as adults from stacked wood or even from pine furniture, and I can imagine that coming home to find a four-centimetre-long stripey creature flying around the bedroom might be enough to give many people pause. The ovipositor is also often misinterpreted as a massive stinger. Not so! Wood wasps are completely harmless to people. The ovipositor is what gives the wood wasp its alternative name of ‘horntail wasp’, which seems to be used on both sides of the Atlantic.
I have a great fondness for wasps and hornets of all kinds – I suppose that their status as the underdogs of the insect world makes them instantly appealing to me. It gladdens my heart whenever anyone resists their instinctive urge to swat an insect and instead becomes curious about what it is. I truly believe that the more you learn about a creature that you’re afraid of, the more measured and reasonable you can be in your approach to it. There’s a wood wasp somewhere winging its way over the the North Circular in search of a branch of IKEA with some Billy pinewood bookcases stacked and ready for shipment, all thanks to my colleague and her compassionate approach.