Pages

Monday, 27 May 2019

Emergence

Along, no doubt, with many other folk, the Bank Holiday weekend saw me busy in the garden. As I stepped out of the back door on Saturday morning, two small, almost transparent, damselflies fluttered away and, almost simultaneously, a much larger dragonfly zipped by. I was briefly annoyed not to get a better look, but didn't think much more about it. Later, however, I happened to glance into our small pond and spotted several more damselflies. Kneeling down for a closer look, I discovered that virtually every emergent plant had a number of spent damselfly cases (exuvia) on them and that newly emerged adults were climbing up the stems, whilst some were still in the act of 'breaking out'.



Some time was spent trying to get to grips with their identification and, even armed with a decent field guide, I was not successful. I had not hitherto appreciated that when they first emerge our Odonata are not yet fully the finished article and may not have acquired their final colours.  Unforgivably, I failed to get a decent photo, with this about the best of a poor bunch -



I think that they are either Common Blue or Azure damselflies, with both species apparently to be found in garden ponds.

Things then got more interesting. A dragonfly was spotted in the water, not looking at all happy. I rescued it, but sadly it succumbed shortly after. This did afford me the chance of identifying it, however, and I was more confident in stating that here was a female Broad-bodied Chaser. Three or four other exuvia were found around the pond, with around ten larvae in view in the shallows, or up on the top of the Hornwort which grows throughout the pond. I'd spotted the rather imposing larvae in the pond before, so it was nice to be able to put a species to them.


Damselflies continued to emerge, albeit in smaller numbers, throughout the morning and early afternoon. It wasn't until around 4pm that I spotted a dragonfly larva crawling out of the water. It fell back in several times, so eventually I helped it out and placed it on some nearby Verbena. It soon crawled up the stem and fastened itself around a leaf. Checking back a little later, I was thrilled to see that the adult was breaking out.


Over the next hour or so, with several rest periods, the dragonfly pulled itself free...



... before eventually pumping up its wings and taking on the recognisable colouration of a female Broad-bodied Chaser...



She stayed put on the stem as darkness fell.

I was out early next morning and she was still in position when I left, and when I returned around 9am, but departed at some point later in the morning. More damselflies were emerging by then, but a more gruesome discovery was four Broad-bodied chaser larvae all caught in spider webs amid the trellis near the pond. One had managed to split out despite the web, but three had died. All were found in a spot which catches the early morning sun, prompting the thought that they must have made their way there overnight, ready to make the most of the brief window before the sun moved further round. I was consoled by spotting another freshly-emerged dragonfly on some Purple Loosestrife. By now it was fairly cloudy and the dragonfly stayed put for some time. I happened to be outside when it eventually took off and watched as it lifted away and flew from the garden... and was immediately intercepted by a male House Sparrow, who took it off up into nextdoor's guttering. Ah, the harsh face of Mother Nature! Ever there to remind us that it's a jungle out there. Kill or be killed and survival of the fittest and all that.

Unsurprisingly, the sparrows have been quick to cotton-on to the food source on their doorstep. Many times today I've looked out to see one searching diligently through the pond-side vegetation and, on one occasion, a male whose beak contained several damselflies. Those dragonfly larvae who met a literal sticky end in the spiderwebs have all been removed. I'm very fond of the resident House Sparrows. Indeed, we've put up some nest boxes specifically for them (as yet unused). They are, of course, ensuring that I will have more House Sparrows to enjoy and I wish them every success. However, a part of me can't help wishing that they'd left the damselflies and dragonflies alone, to fulfil their own destiny and, perhaps, to allow me another look at these remarkable and beautiful creatures next year and to witness, here in our small garden, one of nature's miracles unfold. Fingers crossed that some got through!