Invertebrate survey at Gunpowder Park, the former Royal Ordnance Site in the Lee Valley
Gaps in age structure are likely to have a detrimental affect on species such as the Musk Beetle and
the bees and other insects that collect pollen and nectar from Salix species. A continuity in age
structure should be ensured by suitable pollarding in rotation.
There is some Viper's-bugloss Echium vulgare growing on concrete on the path. This is a valuable
plant for bumblebees and other insects, especially in drought-stressed conditions. Where the path
turns west towards the PFA ponds there is an open area and some bramble scrub. Bramble is
valuable forage resource when in flower as long as it is in the open. However in general much of
the field vegetation in and alongside the osier scrub is rank, with lots of nettle, bindweed, Comfrey
and large Willowherb.
Hedgerows and Field margins
A mature line of Ash along the north side of Cob Fields is likely to have an associated bark fauna
but limited investigation during summer 2003 was not able to confirm this. The hedges possess a
typical hedgerow/ scrub fauna, and they contain a fair amount of dead wood.
A wide strip of established uncut vegetation with some trees and a defunct hedge runs alongside a
ditch adjacent to the southern edge of the Cob Fields, alongside the ditch in Arca B. This has
proved to be an extremely valuable invertebrate habitat. Unfortunately all the standing dead and
partly dead trees were removed during the survey.
The wide field margins to the arable fields are likely to provide insects with valuable summer
forage in the form of mayweeds, etc. There may be opportunities to increase their important
considerably with the introduction of specific forage plants.
Results
The total number of species recorded since August 2002 is 769. This total includes 11 Red Data
Book species, as well as 45 listed as Nationally Scarce and 1 87 listed as Nationally Local. In the
Nationally Scarce species. 7 are listed as Notable A, 27 species as Notable B and 11 as Nationally
Notable. Nine species arc recorded as definitely new to Essex, with a further two possible beetles
new to the county. Sixty-six species are included in the provisional Essex Red Data list (at
www.essexfie1dc1ub.org.uk), and in groups where Essex rarity and threat statuses are defined, eleven
are listed as Essex Threatened and eighteen as Regionally Important. These categories are explained
in Appendix 1.
Despite the lack of official public access to the site during the survey, traps were disturbed and lost
on a number of occasions from two trap sites, resulting in loss of data for two of the new grassland
areas.
By far the most species were collected at Area B (a mini 'river valley' system and ditch/hedge with
remnant flower-rich edges), Area C (the old flower rich grassland) and Area D (the PFA pond edge and
marsh areas). In terms of numbers of Red Data Book and Scarce species the most important areas were
again B, C and D. These areas are described in more detail in the following section.
Despite loss of traps on a number of occasions, Area B2 produced a reasonably high number of species,
including some of significance. This area and similar grasslands on the site are likely to increase in
significance as structural habitat and plant diversity develops, invertebrate species colonise and populations
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