BIRD GUIDING AROUND OSLO

Monday, 22 October 2018

Late Common Darters in Maridalen

I have posted a few pictures of dragonflies this summer and my interest in them is growing although my identification abilities even with good photos is still poor. I find separating Common Darter (sympetrum striolatum) and Vagrant Darter (sympetrum vulgatum) especially difficult and often have to send my pictures to Finn Mosti for help.

On Thursday I was surprised to find a number of darters in Maridalen with both egg laying and mating observed. The birds were clearly weak with it being so late in the season and allowed close approach. One female also seemed to find egg laying too much and her mate just dropped her in the water but I guess her job was done and she could bow out knowing she had fulfilled her destiny.
It was interesting watching them egg laying with the male holding the female by the head and also mating where they are attached in two places with the male holding the females head and them then attached by their sexual organs. In the video you can see the males body pumping as he presumably transfers his sperm to the female.

I had concluded that they were Vagrant Darters based on the shape of the sexual organs but the expert opinion is that they are Common Darters (although the egg laying ones cannot be safely identified from these pictures)


Common Darters/sympetrum striolatum/senhøstlibelle







an unpaired male

another male
presumably also Common Darters





the female after being abondoned by the male once the job was down


No comments:

Post a Comment