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Recorder Report for ants, bees and wasps (aculeate Hymenoptera)
PETER HARVEY
32 Lodge Lane, Grays, Essex RM16 2YP
Introduction
The author has produced 1998 updates to two
volumes of provisional distribution maps
covering Essex and the East Thames Corridor
in south Essex and north Kent The Essex
maps are based on over 12,500 modern
records and include provisional Essex Red
Data status categories. The maps for the East
Thames region are based on approximately
15.000 records and include about 2700 from
north Kent in Gerald Dicker's collection, very-
kindly provided by Liverpool Museum. The
author welcomes further records for Illis
region, winch is under enormous threat from
the 'Thames Gateway' and other development
pressures (e.g. Harvey 1999). Two examples
of the many sites lost to development are
shown in Figs 1 and 2
Coverage in the county
Coverage of aculeate Hymenoptera in Essex
is becoming much more comprehensive due
to the hard work of several Field Club
members and the efforts of Jerry Bowdrey,
Adrian Knowles. Roger Payne and Charles
Watson need a special mention. The
coverage map for tetrads in Essex
(opposite) shows where gaps in the county
remain and the coincidence of species
recorded in each tetrad.
Aculeate biodiversity in the county
Most aculeates need flower-rich vegetation
for foraging or hunting and open sandy
ground in the sun for nesting. Many bee
species are dependent on the pollen from
particular flowers to provision their cells.
Subtle ecological differences between species means the greatest biodiversity almost always
occurs at sites where there are extensive areas of suitable habitat or in larger areas of countryside
winch still provide a rich mosaic of habitat.
These requirements mean that large parts of Essex will support few species of aculeate and
arc unlikely to contain important assemblages - either there is an absence of suitable nesting
sites or the landscape docs not provide the necessary plant species. Even where suitable plants
do survive the wildlife habitats are too fragmented or the plants are not found in the quantity
needed to support aculeate populations. Indeed so much of Essex today presents a species-poor
desert that much of our biodiversity may be on the point of a collapse mirroring the decline of
many bumblebee species in Britain.
In Illis modern scenario it is the 'Brown field' sites which often provide the flower-rich
vegetation and areas of warm sparselv vegetated ground required by many scarce species yet
these arc the very sites most under threat of development. Fundamental changes to agricultural
and planning practices arc needed, not only to retain important sites but also to return to the
mosaic of habitats found in the past.
Essex Naturalist (New Series) 16 (1999)