The aptly named Marmalade fly, Episyrphus balteatus

The Marmalade Fly, Episyrphus balteatus is very common hoverfly. Adults are on the wing right through the year, although in largest numbers in the summer. They feed on nectar, often gathering in very large numbers on flowers like tansy, ragwort and cow parsley. The larvae are predators of aphids. As well as being a common breeding fly, in some years, huge numbers migrate here from the continent when they can be seen busily feeding on flowers near the coast.  Ref; http://www.wildlifetrusts.org/species/marmalade-fly

This one enjoyed a good lick of pollen from a Hemerocallis, (Daylily), in my garden.