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web in cracks in fences, walls, windowframes and similar places. Only the harmless
adult males would normally leave their web. Roger Payne has had the spider present in
his house for a number of years and has yet to be bitten! A related mediterranean species
Steatoda paykulliana is known to bite and has for example affected workers in Spain
picking grapes. It has occasionally been recorded in Britain usually imported with
produce.
I am personally extremely doubtful that these new finds of Steatoda nobilis are due to its
sudden increase and spread. In my view the spider is likely to have been present in Britain
for some time. The spider's habitat makes it difficult to find since it spends most of its
time hidden in cracks and usually only appears on the web in order to to deal with prey.
The web can easily be confused with those of other spiders living in similar places and as
is often the case, if you are not specifically looking for a species it is easily missed.
However there does seem to be a genuine increase in the frequency and range of some
invertebrates. There is fairly convincing evidence that the Bee Wolf Philanthus
triangulum is undergoing a dramatic increase. The regular occurrence of this aculeate
wasp was restricted to the Isle of Wight, with other modern records from Hampshire, N.
Essex and Suffolk. Last year it was found in new localities in Essex, Kent, Norfolk and
Cambridgeshire with possible sightings in Surrey.
This year it has continued to be found in new localities, for example it has been observed
in four West Sussex sites (the first records of this species for the county), at least five new
localities in Surrey, with others in Kent. Many records are of the wasp being found for
the first time in well-known sites (e.g. Horsell Sand Pit, Surrey). Some of these records
are of aggregations of 100 or more nests. A sand pit in Kent was estimated to contain a
minimum total of about 12-15,000 nests! So common were these nests there that the
workmen in the pit dug out the larvae during the winter and fed them to the birds. The
owner of the pit found the wasps there for the first time about two or three years ago
(George Else, personal communication).
The wasp has also continued to turn up in new localities in south Essex, at Fobbing,
Linford, Mill House Pit, Grays and Shoebury East Beach. Certainly at some of these
sites there were quite large nesting aggregations present. At the Chadwell site first
discovered last year the wasp seemed to be present in much larger numbers this year.
Lomholdt in "The Sphecidae (Hymenoptera) of Fennoscandia and Denmark", 1975-6,
mentions what may be a similar expansion of the range of Philanthus in Europe in the
late 1930's probably caused by unusually favouable weather conditions in July and
August.
The Department of Environment report says that there is no evidence that the recent warm
weather in the mild winters and hot summers between 1988 and 1990 was due to the
emission of "greenhouse gases". However the Financial Times article says that a vision
of Britain with a mediterranean climate emerges from the report's 150 pages of statistics.
The grape and sunflower harvests in the south of England flourished during the
abnormally warm weather and gardens bloomed weeks early - and so did the pests! The
agrochemical companies were the real winners with sales of insecticides rising by more
than a third in 1989.
Peter Harvey