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The three
maps we have generated through the NBN Gateway, show the
dramatic decline of the Wall Brown over three periods
since 1980 and the butterfly's range contraction towards
the upland areas of the Pennines and coastal areas. The
Wall Brown seems to have suffered greatest losses from a
large area beginning just south of London, through up
into South Yorkshire, central Wales and Norfolk. Declines and increases in many of
our native butterfly populations are nothing new and
their populations are ever-changing and ever likely to
change in the future, no matter how much we try to help
them.
Remember how the Comma
began an enormous expansion in its UK range back in the
1940's, after being confined to areas near the Welsh
border and other species such as the Speckled Wood,
Gatekeeper, Brown Argus, Dingy Skipper and the Essex
Skipper, have also increased.
These range expansions
have all steadily taken place over a number of years and
are, in these instances, most certainly in direct
response to the recent changes in our climate and which
has suited these butterflies.
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| The Wall
Brown represents a classic example of how our common
insects can suddenly slip away, virtually unnoticed and
without warning. Perhaps more importantly, we should be
aware that all our insects are worthy of care and
protection, no matter how common a distribution map
indicates they are and that conservation bodies and
organisations, should not neccessarily create areas of
habitat to save a few species at the risk of others. Common insects are often largely
ignored by recorders, who can sometimes have a tendency
to send in records that only they regard as being
important. We were asked recently by someone, about who
they should send their rare invertebrate records to. We
replied that they should send all their records to the
county recorder and to send everything and not to filter
out what they think may be interesting or known to be
rare, because we often know more about the rare species
than we do the common. Its amazing how very common
species often get neglected, as every single record is
important in developing a much clearer picture of our
fauna.
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