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Next to be observed were several fine powder-blue
males of the black-tailed Orthetrum (O. cancel-
latum), an increasingly familiar species in
Essex sand and gravel workings. Two other,
closely similar 'darter' dragonflies, the
common and ruddy Sympetrums (S. striolatum
and S. sanguineum) were both present around
a small, well-vegetated pool, and this provided
an excellent opportunity for us to closely study
the differences between them. The common, but
very impressive large 'hawker' dragonfly
Aeshna grandis, and a second common blue damselfly
Enallagma cyathigerum were also seen. The
highlight of the day, unfortunately one I wasn't
able to share with the rest of the group, was
a single sighting of a male white-legged
damselfly (Platycnemis pennipes). This species
is very sensitive to pollution, and is now
known from only two sites in the whole of Essex.
An afternoon walk west from Ulting bridge,
in deteriorating weather, was less productive,
but still of interest. We were able to spend
some time watching a brown hawker (Aeshna
grandis) laying its eggs on a part-submerged
stick at the edge of the canal.
Rivalling the dragonflies for our attentions
was a fine day's total of eighteen butterfly
species. These were: large, small and green
veined whites, brimstone, several clouded
yellows, gatekeeper, meadow brown, small heath,
wall brown, painted lady, peacock, red admiral,
comma, small tortoiseshell, holly blue, common
blue, small copper, Essex skipper and small
skipper. Among the other insects seen were
the day-flying migratory moth, the silver 'y'
two grasshoppers, Chorthippus parallelus and
C. brunneus, and the local Roesel's bush-cricket