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Recording coverage
There are records from all 58 ten km squares covering the county, including the tiny area of
Essex within TQ47. The coverage of recording within the county can be crudely judged from
distribution maps for ubiquitous species such as Nemastoma bimaculatum, Paroligolophus
agrestis and Rilaena triangularis. The Essex maps for these species show a reasonably
comprehensive distribution across the county on both a 10km square and tetrad basis.
Of the 21 species recorded for Essex the number recorded in each 10km or tetrad square
provides another estimate of coverage. A coincidence map for Essex harvestmen species is
given in fig. 1
Fig. 1 The coincidence of harvestmen species recorded in Essex
Biodiversity in Essex
One of the main reasons traditional agriculture in the past may have provided such a good
landscape for many invertebrates and other wildlife is the complex of unimproved grasslands,
pasture, heathlands, woodlands mixed with small disturbed areas created by traditional practices.
Today our national fauna has been decimated by modern fanning practices and by the huge loss
of unimproved habitats to the plough.
Much of Essex is intensively farmed and consists of arable land and provides liabitat only for
the most common species. The most interesting habitats for harvestmen in the county are
woodlands, heathland, unimproved grasslands, marshes and dune.
Many ancient woodlands were coniferised by the Forestry Commision after the war and are
isolated by arable deserts. Some of these coniferised woodlands seem very resilient and are now
showing a remarkable ability to recover when areas of conifer are clear-felled and managed for a
return to deciduous woodland.
Essex Naturalist (New Series) 16 (1999)