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Warwickshire is on the Northern limit of the range of this
species.
Though generally considered a riverine species before 1997 its
stronghold here was the canal system in the east of the county.
Tolerant
of high traffic density and water turbidity it is on occasion
prolific
on stretches of canal as, for example, the Grand Union at
Stockton. It is also insensitive to the nature of the bank, be it
concrete kerbing or more natural. Particularly useful is its habit
of
emerging on the canal concrete kerb enabling the odonatist easily
to
find, collect and count exuvia! In the years following 1997 it
spread
widely on the county river systems, not just from its eastern
stronghold but from the west up the Avon.
In May 1997 it was recorded for the first time in the west of the
county on
the Avon.
In succeeding years its recorded range extended up the Avon and
the
Alne
tributary. In 2002 it was recorded for the first time on the
Stratford
Canal
at Preston Bagot. There has been a less marked trend westward from
the
eastern stronghold of the species. Also, the species seems to more
abundant
on the rivers in the east than it was prior to 1997.
The species is also found at a number of still water sites in the
county, often close to or adjoining its favoured canal habitats.
Breeding behavior is often observed at such sites, including
oviposition.
Successful breeding was confirmed in the county at a still water
site
for the first
time in May 2005 (exuvia were found at Stockton Quarry).
Though the species is now widespread in the county there are
still
areas with suitable riverine and still
water sites where it is unrecorded, see the distribution map.
Records
from these areas of the county are
particularly welcome.
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