Dear Readers, sometimes I get mildly irritated with my pond. It’s true that, because I replaced my lawn, I don’t have to do any mowing. However, I do have to spend time cutting back the reeds and pulling endless leaves and debris out of the water especially at this time of year when a whole whitebeam’s worth seemed to descend in twenty minutes. But then, something happens that reminds me what it’s there for. It might be a whole bunch of singing frogs in the spring time. It might be a wagtail popping down for a drink. Or, as on Sunday, it might be an emperor dragonfly (Anax imperator) looking for somewhere to lay her eggs. I know that she is female not only by her behaviour, but by her colour – female emperors are green and brown, males are electric blue.
What an extraordinary animal she is, as long as my finger and with wings like smoked glass. Her lower left wing has a triangular section missing, possibly following a close encounter with a bird, or even an amorous male. Her eyes cover most of her head like a bifurcated helmet, and each eye has 30,000 individual lenses. They can see all the colours that we can see, plus ultraviolet and polarised light from the surface of water. She is, I know, a ferocious hunter, catching her prey on the wing by outmanoeuvering it. I once watched an emperor dragonfly hawking for speckled wood butterflies in Coldfall Wood, and wondered at his speed and the way that he popped up from underneath the butterfly, snatching it in his jaws and bearing it away with sublime efficiency.
Dragonflies seem to have a streak of curiosity, and to be keen to investigate unknown phenomena. I met a male emperor dragonfly in a Scottish woodland once, and he hovered a few feet from my face at head height. As I turned, he turned with me. I had the most curious sense of being weighed up: friend, foe, or just unimportant feature of the landscape? After a few moments he rattled away like a toy plane, leaving me covered in goosebumps and full of wonder.
But I was worried about this female. She was frantic in her search for somewhere to deposit her eggs, probing the ground with her lime green and chocolate striped abdomen. Most of the time, she seemed to be keen to lay between the wooden slats on the boardwalk beside the pond. This felt like a most unsatisfactory site to me, but how to convince her to lay them somewhere else? She seemed very single-minded.
I went to the kitchen and got a medium sized glass mixing bowl, and a side plate. For all her keen eyesight she was not the least bothered when I covered her up, and only slightly perturbed when I slid the plate under her, gently, to avoid damaging that sensitive abdomen. When she realised she was trapped she tried to fly up, her wings rattling alarmingly against the glass. I carried her a few steps and she turned to face me under the dome. I held the bowl out over the water and lifted it a few inches. She darted out straight at me, and paused a hands-width from my nose. Then she landed on my skirt, explored it as an egg-laying substrate, abandoned it and flew out over the pond, only to return to the boardwalk again. Emperors (or should it be empresses) usually lay their eggs on pond weed, so I think the moss was confusing her, though I have plenty of pond weed left.
If any of her eggs do survive, the nymphs will become the terror of the pond, laying in wait to grasp creatures up to the size of small tadpoles in their forearms. The jaws of the creature in ‘Alien’ were modelled on the complex extending jaws of the dragonfly. These are creatures that are predatory in every part of their lives and they exude the confidence of an animal that is rarely preyed upon, at least in this country. A dragonfly sat happily sunning himself on my bare arm for ten minutes one sunny day a few years ago, enabling me to look at his curious little face to my heart’s content.
Flight has evolved separately at least three times in the insects, and dragonflies were among the first to develop the skill (possibly only preceded by the weak flight of mayflies). Some of the ancestral dragonflies had wingspans of 30 inches. The wings are powered directly by the muscles – in the photo above you can see the bulges where the wings are attached to the body, and the depth of the thorax indicates how large these muscles are. The dragonfly needs to warm these muscles up before it can fly, which explains why you will often see dragonflies perched in south-facing bushes early in the morning. Once ready for action the dragonfly can fly at approximately 30 miles per hour, and has been estimated to accelerate at 4 g in normal flight, and up to 9 g when pursuing prey. Bear in mind that the Space Shuttle only reaches 3 g during launch and re-entry. These animals can also fly in six different directions (including backwards) and have four flight modes for different situations, from static hovering to pursuit of prey. They are, in short, the masters and mistresses of insect flight.
So often, I wish that I could talk to animals. I would have loved to persuade this beauty that she was wasting her precious eggs, but nothing I could do would dissuade her, and so eventually it started to rain, and I left her to it. And also, do I really know better? It’s a kind of hubris to think that I really understand what’s good for this creature and her offspring. I am reminded that interfering has unexpected consequences, and that often it’s better to leave off our meddling, however well intended. So, I shall have to wait and see if any dragonfly larvae turn up next year. In the meantime, travel well, empress. I am delighted to have met you.