Excavator: Ground. The typical nesting behaviour is very similar to that of A. bucephala (qv), in that a cluster of many individual nests are connected by a single, common entrance burrow (Yarrow & Guichard, 1941; Leys, 1978).
On the Continent it has been reported to nest sometimes solitarily, but under favourable conditions in rather large aggregations (Westrich, 1989). In Holland, Leys (1978) reports that a single nesting aggregation may contain up to eighty females, and as many as eleven such groupings have been found in close proximity. Subsequent studies reported by him to the Dutch Entomological Society Meeting in April 1982, describe some two hundred burrows with up to a thousand females each in one meadow, at a density of four burrows to the square metre (a population therefore of two hundred thousand of this rare bee)(Felton, 1991).