Libellula quadrimaculata is generally an early species on the wing, though the earliest
recorded date in Essex during the survey period was the 9th of June. The species is on
the wing through July, and has been seen as late as 20th August.
This species figured in the early lists for the district around Epping (E. Doubleday
(1835). Stephens (1835-7) and H. Doubleday (1871)) and Newman referred (1832-3) to
Libellula praenubila as taken by 'my friends H. & E. Doubleday' at Epping. H.
Doubleday declared L. quadrimaculata to be the commonest species of the family.
It appeared on F. A. Walker's (1897) list for Wanstead Park, and W. H. Harwood (1903)
added Wivenhoe, Colchester and Clacton as Essex localities, but the Wivenhoe
sightings were for one day only, in 1900, presumably the results of immigration.
Harwood also mentioned a large migratory 'swarm' of L. quadrimaculata seen off the
Essex coast in June. 1888. The variety f. praenubila was said to have been met with near
Clacton-on-Sea. Libellula quadrimaculata also appeared on Epping Forest lists
subsequent to those provided by the Doubledays, but the Campion brothers (e.g. 1906,
1908) noted its scarcity in the Forest. E. E. Syms (1929) listed it, as did E. B. Pinniger
(1933), who reported it as common in favourable years. C. O. Hammond's diaries show
it as present in the Forest through the 1920s and subsequently up to 1945. In 1924
Hammond noted it was 'common at all the ponds'. The species was collected at Hatfield
Forest by D. A. Ashwell in 1940, and Pinniger, Syms and Ward (1950) gave Epping
Forest and Wanstead Park as sites where the species was seen in 1949. Longfield (1949b)
noted its local status and scarcity in the London area as surprising, going on to point
out, however, that it had apparently increased as a breeding species in Epping Forest.
She gives 'muddy little ponds', gravel and brick pits, as well as fresh and brackish
marshes as breeding sites for the species.
The present survey bears out Longfields's comments on the scarcity of L.
quadrimaculata as applicable to the whole county of Essex. The historical record shows
evidence of considerable year-by-year fluctuations in populations, presumably as a
result of migrations. This factor continues to confuse our picture of its current status in
Essex. Since 1980 L. quadrimaculata has been recorded from some fourteen sites (ten 10
km. squares) scattered throughout Essex, but particularly concentrated in the north-
east. These sites include forest ponds, flooded sand and gravel pits, and brackish coastal
dykes. Confirmed breeding sites are, however, very few. They include Fingringhoe Wick
Nature Reserve, Glemsford Pits S.S.S.I. and Wake Valley Pond, in Epping Forest.
Orthetrum cancellatum (Linne, 1758) Black-tailed Skimmer
This large darter dragonfly is an increasingly familiar one in Essex. The male has a
dark brown thorax, with blue eyes, and, when fully mature, a powder-blue abdomen
shading to black on the hind segments. The female has mainly an ochreous yellow
colouration, with paired black markings on each abdominal segment. The male of O.
cancellatum could be confused with the male of Libellula depressa, but the abdomen of
the latter is much wider in proportion to its length, and does not have the black 'tail'
of. O. cancellatum. Both sexes of O. cancellatum can be distinguished from all Libellula
spp. by the absence of the dark brown patches at the bases of the wings which are a
feature of the latter.
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