A mining bee?

Observation - A mining bee?. Description: There were lots of these small bees about today. Only .5 in length, they are very active not settling for long on leaves. I did not see any on garden or wild flowers but there are not many in flower yet. My limited insect field guide suggests that this m

There were lots of these small bees about today. Only .5" in length, they are very active not settling for long on leaves. I did not see any on garden or wild flowers but there are not many in flower yet. My limited insect field guide suggests that this might be A haemorrhoa purely because it emerges early but the brown thorax and absence of a coloured tip to the abdomen leaves me with doubts.