More observations about the Speckled Wood

by Steven Goss

I was interested to read the observations

reported by James Mann in the last edition of the Argus about the female Speckled Wood Pararge aegeria that apparently shunned the advances of a male by appearing to have died!

It is well known that the Speckled Wood is a very territorial species. It will mark its territory, usually a patch of sunlit ground, and defend it from other males. It knows it is more likely to attract a female to a sunlit area, and when a female arrives it will approach her in the fashion that James described. As the sun moves, so does the area of ground lit by the sun, and thus a male will find himself constantly having to re-mark the territory he wishes to hold. A bout twenty five years ago I carried out a series of experiments in a wood in Hampshire whereby I introduced marked males and females into existing territories to see what happened. I also introduced pretend butterflies made from paper and attached to fishing line which I tried to make 'dance' in a similar fashion to the males whilst I was perched precariously up a tree above. Great fun! Unfortunately I cannot find my detailed notes, although I do remember the pretend ones were investigated on occasions but quickly ignored. However, there is no doubt that the male observed by James was attempting to mate. The female will typically land in a sunny spot and the male will land nearby and approach her. The female will then either fly away, in which case the male is out of luck, or will sit or lie motionless. The male will then perform an elaborate display in front of her, which includes the apparent prodding of her with his antennae as decribed by James. By now he will be releasing pheromones which tell the female what a fine partner he would make, and be receiving similar information about the state of the female. One of the purposes of my experiments all those years ago when I was about 16 years old, was to try and ascertain whether the male produced a pheromonetype chemical to repel other males during the courtship and mating process. Exactly why the pair that James observed did not mate is impossible to say ... perhaps they knew they were being watched!! (.