Notes on Essex specialities. 6: the mining bee
Colletes halophilus Verhoeff, P.M.F., 1944 (Apidae: Colletinae)
PETER R. HARVEY
32 Lodge Lane, Grays, Essex RM16 2YP
Colletes halophilus (Plate 14) is a large Nationally Scarce (Notable A) colletid bee confined to
coastal areas of England from South-east Yorkshire to South Hampshire (Falk 1991), but it is
particularly common in East Anglia and by the Thames Estuary (Edwards 2000).
The bec is closely associated with the coast, inhabiting the upper margins of saltmarshes where it
nests in bare or sparsely vegetated soil and forages in flower-rich areas. Although a variety of flowers
are probably used, there is a strong preference for Asteraceae, especially Sea Aster Aster tripolium,
which is the main pollen source used by females to stock their nest cells.
In Essex the bee is widespread in areas of Saltmarsh with Sea Aster (see fig. 1). However the localities
which support the largest populations are often those where human intervention has extended the
'upper Saltmarsh' habitat into more extensive areas on artificially produced substrates such as silt
and pulverized fly ash (PFA) lagoons. Particularly good populations occur at West Thurrock PFA
lagoons and at silt lagoons at East Tilbury and Shellhaven.
Fig. 1. Colletes halophilus distribution in Essex and the East Thames Corridor
Essex Naturalist (New Series) 18 (2001)
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