August to November. Females forage on the pollen of Sea Aster Aster
tripolium, although nectar sources include other sources such as
Ragwort. I have found the species to be quite common at Sea Aster
growing in the silt lagoons at East Tilbury and south of Dovercourt,
North Essex. I have also found the bee at Colne Point, West Tilbury
(TQ6575) and Woodham Fenn (TQ8097) near South Woodham Ferrers.
The Essex saltmarshes are likely to be an important stronghold for the
species.
The closely related Colletes succinctus (L.) is associated with heather as
a pollen source and is nationally a much more frequent bee. However
the small amounts of heathland that remain in Essex mean that it is
always likely to be a very rare bee in our county. The species has been
recorded from Essex in the past, but at that time Colletes halophilus had
not been separated from C. succinctus. During August 1993 I decided
to check heather sites in the county to see if C. succinctus was present.
I found the bee flying in numbers around Calluna flowers at Tiptree
Heath (TL8814) and Thundersley Great Common (TQ7989), but not at
Sunshine Plain in Epping Forest, the Backwarden at Danbury Common
or the small relic heather area at Thorndon Park North.
John Felton has determined a male collected at Barking (TQ4682) in
1990 by L. demons. This is a very interesting record since there
cannot be any heather present anywhere near this locality and the bee
must presumably be using another pollen source.
Colletes marginatus Smith is another scarce (Notable A) bee that is
almost exclusively confined to coastal areas where it is typically
associated with wind-blown sands usually on semi-fixed mid dune (Falk,
1991). I took one female of this species (conf. J. Felton) south of
Dovercourt on the 17th August 1993. Here there is an small area of
wind blown sand that amounts to some of the best dune that Essex can
offer! The bee was flying on the semi-fixed dune adjacent to the
Saltmarsh. The robber fly Philonicus albiceps (Meigen) which is also
associated with sandy dune habitats is fairly numerous both here and on
the sandy areas at Colne Point at this time of year.
Hylaeus signatus (Panzer) is one of the largest Hylaeus bees. It is
closely associated with flowers of Reseda in warm, sunny situations.
This is exactly the situation in which I found males and females at the
Chadwell site in 1993, flying around what appears to be the only group
of Reseda plants at the site. The bee is nationally scarce (Notable B)
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