Hi there - the darter has its abdomen sticking straight up - why do they do this please?
No interactions present.
What you described is known as "Sky Pointing" or I have heard the term "obelisking" used. It is believed they do this to prevent over heating by exposing less surface area of the abdomen to the sun.
Chris Brooks - www.dragonfly-images.co.uk
My Flickr site - www.flickr.com/photos/ceb1298
Lat/Lng: 54.2117, -0.3047
OS grid ref: TA106808
Filey Dams Nature Reserve - large lake well vegetated with reeds etc.