Wednesday, 4 September 2013

Last Days of Summer - Part I

With the kids back at school and a good day forecast I thought it was about time I got down to some hardcore dragonhunting before the weather turns again, and what a great day it turned out.

Indeed the omens were good as a male common hawker buzzed the garden as I made a cup of tea after breakfast, passing the ktchen window three times before zipping off, my first garden dragon of the year.

I decided to do the rounds in the valley to tie up a few loose ends, starting at Thornley woods Pond for a bit of Southern hawker action, then Clockburn Lake and Kite Hill in the hope of catching a Migrant hawker or two, and finishing at Far Pasture for an elusive Ruddy Darter.

I hadn't been to Thornley Pond since before the school hols when it had been a bit disappointing, but on arrival today no less than SIX male southern hawkers were in attendance. I was dizzy trying to keep up with all the dogfights and chases, and it was like this for the next hour or so.
Of course this meant the activity was far too hectic to photograph so this is the best arial shot I could manage :O

Male southern hawker in flight
(you think that's bad you should see the ones I rejected !)

And I also managed to capture a brief touchdown :

Only time for one quick pic before he was up again

Eventually a female arrived on the scene and began ovipositing, but I couldn't help feeling it was only a matter of time before one of the rampant males discovered her, and so it proved.

Just as she came close enough for some decent photos she was hijacked and carried off against her will into the trees beyond, mating wheel already formed as they floated upwards into the pines.

It's a sad fact that despite the many characteristics I admire in dragonflies, their sex lives amount to little more than rape and plunder.
Most animals go through some sort of courtship routine, sometimes elaborate, before mating, but probably because dragonflies don't have much time in their short adult lives to pass on the genes, the males will forcibly mate with the first female they come across.
He approaches from behind, clamps his 'claspers' around her neck (sometimes with a vicious bite to subdue her) and signals his body to begin transferring sperm to the right place (males store sperm in a segment at the end of their bodies, even though their penises are higher up) so once he's in position, he will start the semen transfer.
But before semen is transferred he has another task to perform. As (in this case) the female has already mated, males have developed barbs on their penises that serve no other purpose besides scooping a previous suitor's semen out of the female. And this is why many species stay in tandem while the eggs are layed. It's the only sure-fire way a male can ensure his female isn't 'pillaged' by another male before the eggs are fertilized, so ensuring the passing on of his genes to the next generation.  

So you see, an ovipositing female is very vulnerable, and today this happened on three occasions, though the female pictured below somehow managed to avoid forming the mating wheel and wriggled free from her 'suitor' in mid-air. She hid out of sight in the trees while he just came straight back to the pond and continued searching for another female.

Happily egg-laying, until she was rudely interupted.

I tracked another rising couple to one of the pines beyond the pond. Still in the 'wheel' as they alighted about 30ft up I walked round for a closer look, but when I got there and relocated them, only the male remained on the branch, so maybe another plucky female made an escape.

Left hanging on, serves him right.

Stayed in this position for quite some time
maybe can't handle rejection?

Before I left for the next stage of my dragonquest a common hawker made a couple of appearances, both times chased off by the southerns, and there were four common darters (one pair) also present for much of my stay.

Token common darter pic, not as camera-shy as the hawkers 
An interesting first session, but the day was by no means over. Find out tomorrow how I fluked an unbelievable photo opportunity. More jam than Hartley's ;)   


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