(v) Libellula quadrimaculata Although recorded from more than a dozen localities
in Essex, several of these are almost certainly not breeding sites. Where
breeding is established the species should be protected.
(vi) Lestes dryas New sites for this species continue to be reported, so that its status
in Essex seems now to be relatively secure. The Essex populations are of great
importance in national terms, however, so that any site which supports this
species must be regarded as of very high conservation value. Shallow, rush-
filled dykes or pools, especially near the coast or the Thames estuary are
typical habitats. Insensitive ditch clearance, over-grazing and conversion to
arable seem to be the main threats to this species.
(vii) Erythromma najas So far recorded from some fifteen sites in the county. This
very local species requires floating-leaved vegetation. In its very few moving-
water sites it is likely to be adversely affected by an increase in the rate of
flow.
In addition to the above species, any site in Essex which has Libellula depressa. Anax
imperator, Pyrrhosoma nymphula, or Lestes sponsa is likely to be of conservation
significance.
2. Further Recording
(i) Concentrated field recording needs to be done to establish the precise status
and distribution of the seven local species listed above. Brachytron pratense is
easily overlooked, and should be searched for in remaining suitable habitat.
Cordulia aenea should also be searched for in other Epping Forest ponds, and
in any suitable habitat in the surrounding district.
(ii) Our knowledge of the status in Essex of three species in particular - Aeshna
mixta. Sympetrum sanguineum and Libellula quadrimaculata is confused by the
fact that all three are known to be migratory. It seems likely that the
distribution maps give an over-optimistic picture of their status as breeding
species. Careful research is now needed so that a register of known breeding
sites for all three species can be prepared.
(iii) Two species appear to be currently on the verge of extinction in the county, but
may yet re-establish viable breeding populations. These are Coenagrion
pulchellum and Sympetrum danae. The last-known site of the former (the Old
River Lee at Waltham Abbey) should be managed with dragonfly
conservation in mind, and the species should be searched for. especially by
examining known populations of its close relative. Coenagrion puella.
Sympetrum danae has been recorded only once since the 1940s, but does have
well established populations in the London area, beyond our county
boundaries. Conservation work now progressing in Epping Forest, which is
opening up former areas of acid bog. has re-created suitable habitat for the
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