Andrena bees are commonly known as mining bees because they build nests under ground and you find a pile of spoil around the entrance as a result of their excavations. Andrenas form one of the largest groups of bees and there are many similar species. This one, Andrena haemorrhoa, is one of the first to emerge each spring and so is commonly called the early mining bee.
It is not a large species, smaller than a honey bee but not dissimilar in general appearance but the brown, furry thorax and the black abdomen set it apart. In older specimens the brown fur may be rubbed away and the bee can be almost totally smooth black. This is the female by the way, the males are smaller, slightly different in colouration and are seen much less often.
Andrena haemorrhoa emerge in March and can be seen through until June and their nest holes are a common site in garden lawns, amenity grassland (playing fields, etc) as well as on paths and dry ground. They are most often seen on feeding dandelions, blackthorn and sallow.