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The spider Argiope bruennichi in Essex
Argiope bruennichi has always been a very rare spider in Britain, confined to within a few
miles of the south coast of England in Dorset, Hampshire and the Isle of Wight, with
older records for East Sussex and East Kent. However it now seems to be undergoing a
dramatic expansion in its range and the spider turned up last year both in the south and
north of Essex.
These first county records were at One Tree Hill in S. Essex and at Alphamstone in N.
Essex (see Recorder reports in the Essex Naturalist for 1996/97). Subsequently I have
learnt that the father of John Lamoureux also discovered the spider at Blackshots in Grays
last year. I was taken to see this population in August this year and we found Argiope to
be present in huge numbers across a large area of rough grassland and even alongside the
public footpath that runs through an arable field of wheat.
This year I also swept an immature Argiope in July from tall grassland alongside a ditch
and hedge near Orsett and I have recently received reports of further new sightings in the
area: the Trust warden of Grays Chalk Quarry Alan Sadgrove reports that the spider was
found at the quarry during a recent work party and Chris Beale has informed me of the
spider being found during a WATCH meeting on an area of waste ground near St.
Clements Church in West Thurrock. This area of waste ground is also important for other
rare invertebrates, and a number of nationally rare and scarce species are present
including the RDB1 tachinid fly Gymnosoma nitens with its Nationally Scarce host the
bug Sciocoris cursitans, the RDB3 Blue carpenter bee Ceratina cyanea, the Nationally
Scarce (Notable A) spider hunting wasp Aporus unicolor, which preys on the purse-web
spider Atypus affinis, itself very rare in Essex and many others.
The story continues - Argiope has recently been found in Surrey this year (David Baldock
pers, comm.) and apparently it was found in north Kent a couple of years ago (Mike
Edwards pers. comm.). It now seems almost certain that the species will be found at
various sites in between Essex and the south coast, and may even have spread to
Cambridgeshire, Hertfordshire, Suffolk, Norfolk and beyond.
With similar remarkable changes in the past few years to the distribution and abundance
of species such as the Bee wolf Philanthus triangulum it seems that the longer warmer
summers extending later into the autumn (even this year?!) have favoured species that are
mature and active in the late summer period. The Bee wolf was formerly extremely rare
(Nationally Vulnerable RDB2) and virtually confined to the Isle of Wight, yet is now to
be found as far north as Lincolnshire and Lancashire, often in abundance and will nest in
practically any sandy ground with reports of colonies even in the middle of a roundabout
in London.
Argiope, like its relatives Araneus quadratus and the Garden spider Araneus diadematus
matures in the late summer and gravid females and then the webs with their egg sacs will
still be around at least into October. The large orb-web is a significant investment of
resources on the part of the spider and it is unlikely to survive from year to year in areas
which are cut before late autumn. Rough grassland still uncut into late autumn are
definitely worth investigating. Although very distinctive, with the tranverse yellow
abdominal stripes and the zig-zag 'stabilimentum' or thick band of silk on its web, the
spider is still easy to miss amongst the tall vegetation, and it seems difficult to collect by
sweeping, rapidly dropping to ground level when disturbed.
Peter Harvey
Essex Field Club Newsletter No. 27, November 1998-