Willow Emerald oviposition

The first day of autumn was more summery than any day in the last fortnight. Despite being only 7C at five o'clock this morning, the temperature eventually rose to over 20C, with long spells of warm sunshine. 

After a morning working on a report, I took a post-lunch walk along the river, and was delighted to see numerous pairs of Willow Emerald damselflies egg-laying on small Ash and Cherry-plum trees along the edge of the river. The extra shows the female using her ovipositor to deposit an egg into the bark. The scars resulting from this process can be seen quite clearly in the main image.

I hadn't really expected to see them by the river as the British Dragonfly web-site says " Usually near ponds, canals or other still water with overhanging trees. The eggs are laid into the bark of Willow or Alder." The River Nene is quite sluggish, but is definitely flowing water, and I didn't find any on the very many willows in the area.