western side of the site. A small strip of Mill Wood survives and
contains species such as Wood Spurge and Stinking Iris. The sandy
area is excellent for hymenoptera because of the variety of south-facing
sand exposures available for nesting and the uneven nature of the
ground means that there are many small sheltered parts to the site. A
certain amount of regular scrambler-biking has helped to maintain areas
of bare sandy ground, although this cannot be recommended as a
conservation technique. The vegetation shows various degrees of
calcareous influence and is flower-rich, providing an excellent variety of
pollen and nectar sources for the hymenoptera.
Bumble Bees (Family Apidae)
The Shrill Carder Bumblebee Bombus sylvarum Linnaeus is a local and
much declined species which used to be reasonably common in
southern England. Today it is generally elusive and rarely abundant and
has the nationally scarce status Notable B (Falk, 1991). John Felton
has identified this species from a specimen that I collected at Wat Tyler
Country Park in August 1993.
Conclusion
Field work in recent years has shown a number of sites in south Essex
to have a very interesting and important hymenoptera and invertebrate
fauna generally. Of particular interest are several old grassland
sites. The relic grass heath and gorse scrub at Mucking Heath has
produced a remarkable list of invertebrates and the area of old grassland
on Thames Terrace gravels at Chadwell has proved to be of particular
importance for its hymenoptera. The relic dune grassland at Shoebury
Old Ranges is virtually all that remains of the old Shoebury Common.
Despite their relatively small size these sites are extremely important as
representative of the wealth that must have formerly existed in this
area. The south eastern parts of Essex have some very interesting
climatic features and the relationship between these and the invertebrate
fauna would repay thorough investigation. But does enough detailed
historical data on the invertebrate fauna of the region exist? It is
essential that we retain the sites that are left and that there is a
continuity of management.
Ownership by a Local Authority is no safeguard. In the Hadleigh Castle
Country Park, the important Kersey Marsh grazing marsh is apparently
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