Thursday 8 September 2016

Willow Emerald Damselfly at Finedon Pocket Park

I intended to hunt for Southern Hawkers when I visited Finedon Pocket Park on Wed, but instead ended up finding a Willow Emerald Damselfly. Having watched the Peterborough individual for over 1 hour, I was accustomed to some aspects of their behaviour. When I saw an Emerald Damselfly behaving differently, flying among some Willows growing out of the water, my interest was stimulated. ID was confirmed by zooming in on my photos. If you are not familiar with this species, it differs from the standard Emerald in three basic ways (in males): the pterostigma are pale, bordered with dark, whereas the Emerald has dark pterostigma; the male lacks the blue pruinescence; the male's claspers are much exagerated. There were Emeralds around, along with many Common and Ruddy Darters including ovipositing pairs. I did find two male Southern Hawkers, ovipositing Emperor and Brown Hawkers and some Azure Damselflies.

The sighting of Willow Emeralds in Northants is very exciting for us as they are about the most westerly ever recorded. I am sure there are many more out there, so please keep an eye out on Willow trees overhanging water. Their flight period lasts until November so we still have time to find more. Good hunting and please let me know if you find some - ideally females and ovipositing pairs, or even the characteristic egg scars in Willow branches.


Common Darter

Male Willow Emerald Damselfly

Ovipositing Brown Hawker (one of my favourite shots this year!)