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The Essex Naturalist
Nomad bees (Family Anthophoridae)
Males and females of the Nationally Scarce (Notable B) Nomada flavopicta, were
collected at West Thurrock in August 1996 at St. Clements Church tract and
the nearby West Thurrock PFA lagoons. The species is a cleptoparasite of
Melitta leporina and M. tricincta both present at the sites. Two females of the
Nationally Rare (RDB3) Nomada fulvicornis were taken in August 1996 at West
Thurrock PFA lagoons where one of the hosts Andrena spectabilis was also seen.
Nomada striata, a cleptoparasite of Andrena wilkella rare in the county, has been
taken at two new sites at Gravelpit Farm Pits in Thurrock and Warren Pit near
Woodham Walter. The most exciting Nomada however has been the Nationally
Endangered (RDB1) Nomada xanthosticta which was present in some numbers at
Glemsford Pits in April 1996 and taken there on the April by Colin Plant, Peter
Yeo and myself around sallow at the edges of an area of lichen heath (Harvey,
1996a). The species is a cleptoparasite of Andrena praecox, which collects pollen
from Salix and which occurred at the locality, although not apparently in
particularly large numbers, nesting along the bank between the lichen heath and
the old disused railway line, the first record for Essex.
Blue Carpenter bee (Family Xylocopidae)
The Nationally Scarce (RDB.3) Ceratina cyanea was first recorded in Essex by
Harwood (1884). It was not recorded again in the county until in
August/September 1993 it was found at Mill Wood Pit in Thurrock where
subsequent observations showed it to be present in considerable numbers
(Harvey 1993b and Harvey 1994). This locality will soon be lost to housing
development, but much smaller numbers of individuals have been seen in 1996
and 1997 at nearby sites at St. Clements Church tract and West Thurrock PFA
lagoons. A single female was also found at Alphamstone on 13th June 1996, the
first record for North Essex since Harwood's time.
Bumblebees (Family Apidae)
Bombus sylvarum is a much declined species which used to be reasonably
common in southern England (Falk 1991). The species has been included by the
Biodiversity Challenge Group in the top 100 priority list of species for target
action plans in Great Britain. Comprehensive searches to locate extant
populations in Britain this year have only resulted in records at three sites (Mike
Edwards, BWARS AGM) and the species is close to extinction in the British
Isles. Widespread loss and fragmentation of habitat seem to be the main reasons
for this dramatic decline and the cold wet May in 1996 and the poor spring and
early summer this year may have delivered the final blow. Although populations
of this bumblebee were recorded at Ferry Fields, Tilbury on several occasions in
August 1994 together with numbers of the Hornet robber fly, another rare insect
included on the Biodiversity Groups top 100 priority list, English Nature did not
see fit to act to dissuade Thurrock Council from allowing development of the