For me, the summer school holidays are something to be endured. We endure it by being at home leaving the rest of the normally civilized world to be invaded by ear-shattering screamers. However, last summer I added dragonfly and damselfly (collectively, Odonata) spotting to my long-standing love of butterfly spotting and had a great time pursuing my new-found hobby at local nature reserves. Last year was a terrific year for butterflies with a diverse population being boosted by a quite well publicized “invasion” from the continent of Painted Ladies. Being a complete novice, I had no previous experience of Odonata levels but I did find a lot of activity.
This year, I was looking forward to some repeat nature spotting rather than thinking that half my summer had been hijacked. It seems to have been a tough year for our poor ol’ butterfly population. I’ve lost count of the number of sizeable Buddleia bushes I’ve seen without a single butterfly feeding on them. In fact, I’m hard pressed to recall any Buddleia with a butterfly on it. I suspect that our last, particularly harsh winter was at least partly responsible. On top of a bad winter, late July and August have been pants too, weather-wise.
Having said that, I did get out to our local Sandhouse Lane Nature reserve once or twice on days that were half-way reasonable. The level of Odonata activity definitely seemed lower than last year but a few of the more usual suspects were busily trying to make up for the apparent shortfall in population. The way most dragonflies go about adding to the population is that the male of the species spots a willing female of the species and grabs her by the neck using his appendages – projections from his abdomen designed for grabbing ladies around the neck. They are now in the so-called tandem formation. Eventually, still held firmly by the neck, the female curves her abdomen around and under the male to marry her vulvar scale to his secondary sex organ. The resulting circular formation is often called the copulation wheel or, perhaps more romantically, the copulation heart. Damselflies, in particular, form a very definite heart shape.
The most populous dragonfly species at Sandhouse Lane seems to be the Ruddy Darter. On my earlier (and sunnier) trip I had snapped a pair of Ruddy Darters “in tandem” preparing to mate. As usual in the animal world, it is the male dragonfly that is the more colourful and, as a result, often more readily identified. The female tends to be somewhat more drab, often brown/beige/dull yellow, and rather more similar looking. I have, in the past, frequently relied upon the fact that a female is firmly attached to a male to confirm an identification. Here, also confirmed by good old iSpot, is my sunlit tandem pair of Ruddy Darters.
As well as Ruddy Darters, Sandhouse Lane plays home to a population of Common Darters. On a subsequent and less sunny visit, once again I spotted a Ruddy Darter male firmly grasping a female by the neck. I again snapped the tandem pair, just because I could. Upon later study, I thought the female exhibited a different colouration from that in my first pair. In fact, this female looked more the colour of a male Common Darter. “Arghh! Wait – don’t panic!” I spotted that, colour aside, this specimen’s abdomen shape confirmed it to be female. All was well. I added it to iSpot to see if this apparent colour variation of the female might be age-related; they do, sometimes, darken and change with age.
Good decision! it transpires that this poor old male Ruddy Darter had, in fact, grabbed a female Common Darter by the neck. Well, at least he’d got the sex right, if not the species. What a turn up for the books. One of the resident specialists on iSpot had observed this sort of mismatch before but hadn’t got a decent photograph of such a pairing. Having put me straight, he requested a copy of the picture which I was happy to provide.
So, no more identifying females just because they are attached to a male.
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