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After lunch the party moved on to Waterhall
Meadows, a newly acquired Trust reserve,
where we were fortunate enough to be shown
round by the warden Jane Chave. Jane has
herself recorded the dragon-flies of the
reserve, and we were lucky enough to see a
good proportion of the species she has
noted. The most important of these is the
delicate, pale blue 'white legged' damselfly
(Platycnemis pennipes). This is very scarce
indeed in Essex, and is in rapid decline
elsewhere in Britain, too. The thriving
colony on this reserve is quite a feather
in the cap of the Essex Naturalists' Trust!
We also had the delight of observing two
emperor dragon-flies (Anax imperator)on the
Sandon brook. One, a male, was hawking for
insects (at one point it took a small-
tortoiseshell butterfly, but in the end was
unable to deal with it and had to drop it,
badly damaged, into the brook). The other,
a female, was observed for some time as it
dipped its abdomen below the surface of the
water to lay its eggs. Other Odonata
present were: E. cyathigerum (abundant),
Ischnura elegans, Agrion splendens (by now
fewer in numbers than earlier in the season,
Jane explained), Sympetrum striolatum,
S. sanguineum, and A. grandis.
Surprisingly, the only 'Orthopteran' recorded
was the dark bush cricket, whilst the Syrphid
flies included Syrphus balteatus, Platy-
chirus albimanus, Cheilosia illustrata (a
bumble-bee mimic) and the very scarce Xantho-
gramma pedissequum (a wasp mimic, with
characteristic yellow and black markings on
both abdomen and thorax) . Common frogs
and a previously un-noticed patch of the rare