Oviposition site

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Mate, no – you don’t want to be…
Look, it’s not a good idea…
No, really – wait, no – but…
Look, just stop, woman, would you?? Go and do it SOMEWHERE ELSE!!

I was happy and relieved to see this female Southern Hawker at our neighbours’ pond this afternoon. Last year the village was buzzing with Southern Hawkers, and several different individuals oviposited around our wildlife pond, but this year I’ve seen very few anywhere in the valley – this being only the second female – and I haven’t caught any oviposition at all happening in our garden. It’s clearly been something of a fallow year for the species, and because that’s unusual here it’s been causing me some concern.

However when I strolled along the lane today to see if J and S’s pond was doing better than ours, I spotted this lovely female almost at once, working around it in search of good egg-laying substrates. There’s a little ornamental Giverny-type bridge at the back of this pond, and within a few seconds she disappeared underneath it, hidden by a bank of reeds, but clearly audible by the rustling of her wings against the foliage.

A few seconds later a male swooped in and began looking for her, but luckily for her dragonflies have no organ of hearing, and though I knew where she was I wasn’t telling, so after a couple of minutes of searching he flew away to look elsewhere. One of the many interesting things about dragonflies is that the females fertilise their eggs as they are about to lay them, by moving sperm from a receptacle chamber where it was placed (in a lump called a sperm packet, in the case of Southern Hawkers) by their most recent sexual partner. A further fun fact is that a male dragon is able to clean out any predecessor sperm remaining in a female’s sperm receptacle before inseminating her himself, which is why it’s worth his while to catch her even while she’s ovipositing: the eggs remaining in her current batch can still be fertilised by him.

Given all of this, and the aggression shown by male Southern Hawkers towards a reluctant female, it’s hardly surprising that the females tend to be secretive ovipositors, often stopping laying and remaining very still if they become aware of males patrolling nearby. In this case though I doubt that the female was aware, because she was under the bridge and wouldn’t have been able to see the male overflying the pond, and the noise of her moving around carried on throughout his search. A few minutes after he left she emerged and began working around the pond edge herself, but she seemed unhappy with every surface she tested, and quickly moved on. I was trying to get a better angle for a photo I was lining up when she noticed my shoe, and the next thing I knew she was testing that too. After failing with the rubber she moved on to the leather upper, and in the end I had to shake my foot to dissuade her – and even then she flew back around my feet a few times, apparently thinking about giving it another try.

Southern Hawkers are well known for making creative choices about their oviposition sites, and this isn’t the first time I’ve been one of them, but I was keen for this female not to waste any of her eggs on my footwear. After the eggs hatch in the spring, the minuscule prolarvae are believed to hurl themselves at the nearest body of water, and given that they’re often laid some distance away, they must be quite athletic – but somehow I doubt their ability to get to the wildlife pond at the bottom of our garden from the shoe rack in the utility room.