No interactions present.
From digging about in tree stump water holes and every conceivable bit of muck, dirt and stagnant water since i was a kid I have always wondered what these creatures are? Thank you. Great ob.
Syrphus is right that we can't confirm this as being in genus Eristalis, e.g. in woodland rot-holes Myathropa is a distinct possibility, as are some rarer species.
Entomologist and biological recorder
Lat/Lng: 51.609528942482, -0.15954449772835
OS grid ref: TQ275916
A small pond within the wood which is a small local nature reserve.