Invertebrate survey at Gunpowder Park, the former Royal Ordnance Site in the Lee Valley
Philodromidae Philodromus albidus Notable/Nb, Essex Red Data species. Regionally Important
The species was beaten off scrub in Areas B and D at the Former Royal Ordnance site. It is confined to
the southern half of England. It is usually found in broad-leaved or mixed woodland on the lower
branches of broad-leavcd trees such as oak at the edge of clearings or rides. It is also found in old
hedgerows and green lanes, with the majority of records from trees or bushes at the edge of clearings or
in hedgerows. It seems to have increased in frequency in recent years and is likely to be demoted in
status in a forthcoming review. The majority of records are from trees or bushes at the edge of
clearings or in hedgerows. Lack of management resulting in the closure of open woodland and the
loss of old hedgerows are almost certainly detrimental to this species. Spray drift from the use of
pesticides on crops is likely to affect the survival of this spider, as well as many other invertebrates,
where arabic fields arc adjacent to woodland or hedgerows. Management should retain open
surroundings by rotational cutting of woodland ride vegetation, periodic control of scrub and tree
invasion and light grazing in woodland pasture. The retention of wide field edges and headlands
should be encouraged to help maintain a diverse invertebrate fauna and reduce the effects of spray
drift on old trees in hedgerows and at the edge of woodland (Harvey et al. 2002).
Philodromidae Philodromus praedatus Notable/Nb, Essex Red Data species, Regionally Important
The species was beaten off trees in the defunct hedgerow along Area B, but may also occur at the edge
of Area D. It is usually found in broad-leaved or mixed woodland on the lower branches of broad-leaved
trees such as oak at the edge of clearings or rides. It is also found in old hedgerows and green lanes.
Previously difficult to identify, it has been widely recorded in recent years and is likely to be demoted in
status in a forthcoming review. The majority of records are from mature oak trees in open woodland
habitat, at the edge of clearings or in hedgerows. This type of habitat is threatened by lack of
management resulting in the closure of open woodland, the loss of old trees and the use of pesticides
on crops where old oak trees occur in land converted to arable or old hedgerows are adjacent to
arable fields (Harvey et al. 2002).
Tetragnathidae Tetragnatha pinicola Notable/Nb, Essex Red Data species, Regionally Important
The species was swept in Area C. It is usually found in broad-leaved or mixed woodland on herbage
in clearings or rides, but sometimes, as here, on tall herbage in unmanaged grassland. In Essex it is
relatively widespread and frequent.
Theridiidae Theridion pictum Local, Essex Red Data species, Essex Threatened
Theridion pictum is widespread in much of England, but absent or very localised in the north and
west of Britain and parts of the south. In Essex it has a very restricted distribution, occurring only
in the Lee and Stort valleys, near Wrabness and in the Ingrebourne Valley in Havering. The webs of
this species can be found on a variety of shrubs, herbaceous plants and structures including post
and rail fences. It occurs mainly in damp places in the lowlands. It has also been found in moss and
litter in wetland sites (Harvey et al 2002).
Theridiidae Theridion pinastri RDBK, Essex Red Data species, Essex Threatened
The species was swept from flower rich grassland by the side of the ditch under defunct trees in
Arca B at the Royal Ordnance site. The spider was first recorded in Britain as a male at Chobham
Common, Surrey in 1977 with a female taken in the same vicinity in 1984. There have been a
number of more recent records and further unpublished records in South Essex, West Kent and
Essex Naturalist (New Series) 21 (2004)
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