Falk notes these bees are typically seen nesting in loose aggregations along sandy paths in south-facing slopes and banks. He also notes a variety of habitats, that includes coastal grassland, soft rock, cliffs, moorland edge and occasionally brownfield sites as well as open heathy woodland.
In this instance, there was a combination of some of these elements. Along side the wooded coastal walk, a side path dipped down a little to a sunny bank with a sparse brownfield area opposite. I instinctively followed this path - due to the flowers and sunshine, I felt sure I'd see something worthwhile.
The sunny bank was south facing, with bramble and hawthorn hedgerow, and rich with a variety of wildflowers, from umbellifers, daisies, and dandelions to vetches and green alkanet as well as oil oil seed rape that has seeded along the way. Clearly, there were plenty of flowers for Andrena augustior to forage upon, and there were plenty of bees and butterflies around generally. I felt sure there would be nests somewhere, and indeed, in bare patches of dry, sandy soil, I saw the tell tale signs of mining bees: entrance holes to their underground burrows.
Unfortunately I was not quick enough to capture a quality photograph of groove-faced mining bees entering and exiting the burrows. However, I took a picture of the nest area, and have highlighted some of the burrows as you can see.
Groove-faced mining bees are active from mid-April to late July. These photographs were taken in May.
I captured a couple of photographs of this bee foraging on the green alkanet. Note the relatively long antennae and tufty pale hair around the thorax of this female.
Again - below in flight and a rear view - you can see the hairs on the body, but there is not a lot of it!
Falk lists Nomada fabricana as being a cleptoparasite of this species. I didn't see this particular Nomada, although I did see other nomad bees around. However, there may have been other potential hosts. Still, I am open minded that Andrena augustior could be a target for more than one nomad bee species.