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The Essex Naturalist
regional basis of the most vulnerable species is extremely important so that their
conservation can be incorporated into the planning process and management of
land.
There are very wide differences between counties in the degree of knowledge
about the distribution of species within different invertebrate groups. For most
species it is extremely difficult to assess any changes in regional distribution
because of the paucity of historical information. Old records are often very
limited in their extent and can be difficult to assign to modern distribution
maps. Modern fieldwork may also be very limited in its coverage, not surprising
when one considers both the enormous amount of time required to adequately
cover even a small county and fact that most records are made by dedicated
"amateur" naturalists in their spare time.
Assessment of sites
Falk (1998) draws attention to the problems of variable quality of invertebrate
information found in Environmental Assessments and Appraisals and proposes
the use of Individual Species Impact Assessments as a standardized technique to
overcome many of the problems described in his paper. Ecological assessments
especially those carried out on behalf of developers are frequently unsatisfactory
in a number of ways: they may be based on very limited survey and taxa and
undertaken in widely variable conditions, carried out at inappropriate seasons
using limited survey techniques and hopelessly inadequate survey time.
Ecological assessments undertaken for developers are particularly prone to
inadequate survey and scientifically unsound and bias interpretation. Often a
one day survey, carried out at an unsuitable time of year, in unsuitable weather
conditions may constitute all that is required to push forward a planning
application for a site known to have nature conservation interest. These
ecological assessments are usually confidential and are not open to public
scrutiny unless they become available with a planning application or at a public
inquiry.
The regional significance of data is rarely taken account of in ecological
assessments and whilst very little up-to-date data on the regional status of
different taxa is published, many counties do possess Wildlife Trusts, Field
Clubs and regional experts or county recorders who hold large amounts of data
and local knowledge. Where there are attempts in ecological assessments to
interpret data in a regional context, the interpretation may have no
supporting scientific evidence and quite obviously written to support the
developer's case.
Partly to prevent this kind of abuse the present paper includes regional rarity
and threat status categories and proposes their use for other taxa.