are for aggregations of 100 or more nests. A sand pit near Maidstone
in Kent was estimated to contain a minimum total of about 12-15,000
nests! (G. Else pers. comm.).
In S. Essex I found the wasp for the first time at Chadwell in July 1992
where it was nesting in some numbers. In 1993 the population was
numerous and there must have been hundreds of nesting females in
different parts of the site. In early July 1993 I also found a large
number at a sand pit at Linford, and in August several were found
nesting in a sandy path at a hillside at Fobbing (TQ7183) with others
hunting amongst herbage and scrub nearby. I found a single female
hunting at Mucking Heath and one late female in early September at Mill
Wood House Pit where the presence of favourable habitat conditions
suggests that a large population may in fact occur. In 1992 Roger
Payne found the wasp to be present at Shoebury Old Ranges (TQ9284)
and in 1993 also at East Shoebury Beach. It will be interesting to
follow the future progress of this remarkable increase in the Bee wolf in
Britain.
Social wasps (Family Vespidae)
Dolichovespula media (Retzuis) is a recent addition to the British list
which is also clearly increasing in frequency. The first British record
was from E. Sussex in 1980 but since then it has spread westwards
and northwards. The first Essex record was in 1990 and it is still
spreading (R. Payne, 1992). It has been recorded from north-west,
north-east and south-east Essex and this year I know of records from
Braintree and also from Strethall (S. & C. Watson, 1993).
The Hornet Vespa crabro had apparently declined in the county and was
considered a rare insect but in recent years it has been recorded again in
many parts of the county. This increase in frequency has been noted by
members of the Field Club in correspondence and notes reported in the
Newsletters of the Club.
Mining bees
Family Colletidae
The nationally scarce (Notable A) bee Colletes halophilus Verhoeff is a
specialist of the upper margins of saltmarshes where it requires bare or
sparsely vegetated soil. The bee is active very late in the year from
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