to the south-east Essex sites also confirmed the continued breeding status of L. dryas
there. Also, in July and August, 1984. further searches brought to light other colonies
along the Thames estuary and K. M. Rowland found one female on yet another area of
coastal marsh in the north-east of the county. It has yet to be established whether the
species is actually breeding at this site and another inland locality discovered by R. G.
Payne.
By the end of 1985, L. dryas had been recorded from a total often 10 km. squares in
east and south Essex. The majority of sites are in coastal or estuarine marshes, in dykes
or pools which are often choked with emergent vegetation. Sea Club-rush seems to be a
common feature to these sites and the species is also clearly tolerant of brackish water.
In those sites which have been surveyed so far, other Odonata associated with L. dryas
are the damselflies Ischnura elegans (five sites out of five). Lestes sponsa (four sites out of
five) and the dragonfly Sympetrum sanguineum (four sites out of five). I. elegans is such a
common damselfly that the association is hardly significant, but the link with both L.
sponsa and S. sanguineum bears out N. W. Moore's findings.
Although it cannot be ruled out that L. dryas had, indeed, become extinct in England,
and that the recently discovered colonies have been established by immigration, the
evidence to me seems to point against this. Longfield (1949 a) states that the species is
not migratory but it is certainly a 'wanderer'. This would be expected given the transitory
nature of its habitat. The species is. presumably, equipped with the ability to move on
and colonise new habitats as old ones dry out and become unsuitable. This would
explain occasional sightings of individuals in what look like uncharacteristic or
unsuitable habitats. The literature quotes disappearance of the species from well-
established and well known sites, especially on Thames-side, whereas several of the
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