As a group snipe flies are fairly easy to identity having quite long, thin bodies, long, thin wings and long legs! They can be quite colourful and some are quite large whilst others less so. There are five species of snipe fly commonly seen in Britain although none are actually that common.
The casual name for this species is the downlooker snipe fly (Rhagio scolopacea) and yes, its preferred point of view is to perch on a tree trunk looking down at the ground! They can be seen as adults in May through until August. Their larvae live in leaf litter and are predatory on very small insects and other life that inhabits leaf litter.