I think it's a hoverfly, but can't recognise the pattern.
No interactions present.
It may be a species of Melanostoma or Platycheirus, but it is infected by an entomophthora fungus, or something similar, producing the white bands at the joint of the tergites.
My Flickr photos...
the odd markings. Thanks for that.
Lat/Lng: 54.59269, -1.370123
OS grid ref: NZ407221
Disused railway line, becoming a de facto landfill site!