two hundred and fifty individuals. He noted the great variability of the markings in the
male (especially abdominal segments 2 and 9) and female (especially abdominal
segment 9). His observations were published in the Entomologist's Gazette in 1952.
Gardner re-visited the site on June 22nd. 1952. but found only seventeen individuals,
including, however, two typical males (Gardner, 1953). Then came the disastrous east
coast floods of early 1953. when Canvey Island and the surrounding area were hit by
three tidal waves which breached the sea walls. On July 26th Gardner visited the site, but
found the marginal vegetation badly grazed by cattle, the Water Crowfoot gone, and the
pond, now very saline, covered by a filamentous alga. A few adults and one larva of
Ischnura elegans were the sole surviving Odonata (Gardner. 1954). Longfield also made
mention of the effects of the flooding on the C. scitulum colony in her dragonfly report
for 1953 (Longfield. 1954). Noting that fortunately Gardner had been able to study its
life-history, she concluded: 'It is too early to say that no remnant has escaped the floods,
but none were seen in the summer of 1953 and there does not seem to be any other
suitable area in the district, in which it could have survived. All of its known habitats
were under the floods.'
Despite many subsequent searches. C. scitulum has not so far been rediscovered.
Gardner (1954) speculated that the species may have been brought to the Thames
estuary by favourable air-currents, or possibly by shipping during the later years of the
war. Since the area had previously been well-studied by entomologists it seems unlikely
that it had been overlooked. Though the species has not been recorded during the
present period of more active interest in dragonflies, the remote possibility remains that
a surviving colony may yet be found, or. indeed, a re-colonisation may take place.
Coenagrion puella (Linne, 1758) Azure Damselfly
This is one of our three common blue damselflies. The adult male is predominantly
blue, with black markings. These include, in typical examples, a 'U'-shaped marking on
segment two of the abdomen. Segment 8 and the anterior half of segment9 are also clear
blue in typical males. Typical females are almost wholly black, but with a narrow
greenish stripe at the anterior edge of the abdominal segments, and a black 'thistle'
marking against a green background on segment two. However, the black markings in
the males are variable and may overlap with those of Coenagrion pulchellum. There is
also a blue form of the female which occurs regularly in Essex. This has reduced black
markings which closely resemble those of female C. pulchellum. There is undoubtedly
some confusion in past recording of these species, and great care should be taken to
ensure correct identification when C. pulchellum is recorded (see Appendix C).
The species inhabits a wide range of still and slow-moving waters, such as lakes,
canals, flooded pits and coastal ditches. It prefers richly vegetated, unpolluted sites, and
does not seem to require open water (i.e. it appears to thrive in ponds and ditches
entirely 'choked' with emergent vegetation). Males of the species may be observed in
what is presumably territorial combat. The flight period observed for Essex between
1980 and 1987 was from the last week in May until late August. As with some other
spring species, this flight period seems rather shorter in Essex than elsewhere in
southern Britain. Also, the flight period of C. puella is significantly shorter than Ischnura
elegans and Enallagma cyathigerum, the two other common 'blue and black' damselflies.
This has probably resulted in a degree of relative under-recording of C. puella, and its
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